Mangan

Mangan: Berkah atau Petaka? Oleh: Herry Naif

Pulau Timor adalah salah satu pulau di Provinsi Nusa Tenggara Timur (NTT) selain Pulau Flores, Sumba, Alor dan berbagai pulau kecil lainnya. Isi perut pulau Timor, yang sering disebut Nusa Cendana, didominasi oleh mineral Mangan. Mangan adalah unsur kimia yang digunakan untuk peleburan logam (metalurgi) proses produksi besi baja, baterai kering, keramik dan gelas. Jika mangan terserap oleh tubuh dalam jumlah banyak, akibatnya dapat merusak hati, membuat iritasi, karsinogen atau menyebabkan kanker pada manusia, hewan dan tumbuhan melalui rantai makanan.

Kini, potensi mangan sedang dikampanyekan secara luas baik oleh pemerintah maupun pihak swasta. Mangan dinilai sebagai potensi mineral yang memiliki nilai jual dimana menarik banyak pemodal berdatangan ke pulau tersebut. Hal ini pun disambut gencar oleh rakyat (masyarakat) di Pulau Timor yang sedang dilanda gagal panen, akibat sedikitnya curah hujan pada musim tanam petani.

Penambangan mangan seakan menjadi pilihan alternatif bagi masyarakat Timor dalam memenuhi kebutuhan hidup, tanpa mengerti dampak kerusakan yang ditimbulkan, baik itu terhadap kondisi ekologi yang diambang kegentingan, sosial- budaya yang makin renggang dari waktu ke waktu, dan bahkan kesehatan masyarakat Timor yang makin terpuruk. Hasil Pantauan

Pertambangan Mangan di Biinmaffo (Biboki, Insana dan Miomaffo), Kabupaten Timor Tengah Utara (TTU) dan Timor umumnya adalah penambangan mangan yang dilakukan rakyat. Menurut pengakuan warga, awalnya mereka sama-sama mengambil mangan yang tampak di permukaan tanah namun ada korban jiwa yang terus- menerus di beberapa tempat, sehingga sebagian orang kemudian meninggalkan aktivitas itu. Sekarang para penambang sudah harus menggali tanah beberapa meter karena mangan di atas permukaan tanah sudah mulai kurang bahkan tidak ada lagi.

Dalam tradisi masyarakat TTU (Dawan), mangan disebutnya fatu metan atau fatu pah yang tidak boleh diganggu apalagi dipindahkan siapa pun. Dulu bila mangan muncul di kebun, kemudian diposisikan pada tempat yang layak dan dijadikan sebagai tempat persembahan di kebun itu. Fatu metan diyakini memiliki nilai mistik-magis yang sangat dihormati masyarakat Dawan. Oleh karena itu sampai kapan pun, tidak boleh diapa-apakan. Bila dilanggar, akan terjadi bencana atau peristiwa yang luar biasa dan membawa korban.

Kepercayaan ini kemudian tergerus zaman kapitalistik dimana modal menguasai manusia dan angan-angan kesejahteraan akan digapai melalui penambangan mangan. Dalam perjalanan, ternyata fatu metan ini bukannya membawa kesejahteraan tetapi malah mengantar jiwa orang karena tertimbun tanah.

Fakta ditemukan bahwa penambang tidak dilengkapi pelindung tubuh, misalnya masker pelindung mata, mulut, hidung dan kaos tangan. Para penambang pun tidak menggunakan perlengkapan itu karena mereka juga tidak pernah diinformasikan mengenai dampaknya bagi kesehatan, terutama pada pernapasan. Mereka melakukan aktivitas itu selayaknya bekerja kebun. Padahal, apabila mangan itu diserap tubuh terlalu banyak ia sanggup merusak hati, membuat iritasi, karsinogen atau menyebabkan kanker pada manusia, hewan dan tumbuhan melalui rantai makanan.

Analisis Daya Rusak Tambang Mangan di Kabupaten TTU:

Dampak Ekologi Perubahan Bentangan Alam (landscape) Luas wilayah kabupaten TTU adalah 2.669.70 km2 atau 5,6% dari Luas Provinsi NTT, sedangkan luas laut Kabupaten TTU adalah 950 km2. Dari luas wilayah daratan ini, diklasifikasi bahwa tanah yang rawan erosi seluas 142, 99 Ha (39,4%) sedangkan tanah yang relatif stabil seluas 161, 74 (60,6%) (lihat: Timor Tengah Utara dalam Angka 2006/2007, BPS TTU dan BAPEDA TTU).

Dari data ini dapat dikaji bahwa penggalian dan pengambilan mangan di Kabupaten TTU yang dilegitimasi dalam 82 Surat Kuasa Pertambangan (SKP), tentunya akan menggusur ribuan lahan pertanian, peternakan, hutan, dan sumber air (hidrologi).

Aktivitas penambangan mangan juga dinilai menyebabkan terganggunya tata air setempat, resiko bencana, longsor serta banjir. Kondisi ini diperparah dengan tanah rawan erosi seluas 142,99 Ha (39,4%), karena permukaan tanah dikupas, digali, menjadi lubang-lubang, dan hilangnya keanekaragaman hayati di kabupaten TTU, akibat perubahan bentangan alam dan kerusakan ekologi.

Struktur perekonomian Kabupaten TTU didominasi oleh sektor pertanian (74,7%) khususnya sub-sektor tanaman pangan yang menjadi tempat bagi sebagian besar masyarakatnya mencari sumber penghasilan, sehingga keberadaan dan keberlangsungan sub sektor ini menjadi sangat strategis (lihat: Timor Tengah Utara dalam Angka 2006/2007, BPS TTU dan BAPEDA TTU).

Kabupaten TTU dikenal sebagai wilayah yang sangat cocok dalam pengembangan peternakan (sapi, kerbau, babi, kambing, dll). Itu berarti, dengan 82 Surat Kuasa Pertambangan (SKP) berdampak pada menurunnya kualitas lingkungan yang tidak akan menunjang pengembangan pertanian dan peternakan. Itikad Pemerintah Kabupaten TTU dalam Panca Program strategis dengan memfokuskan sektor pertanian khususnya tanaman pangan menjadi salah satu program utama dalam mengkatalisasi pertumbuhan ekonomi daerah, hanyalah sebuah mimpi, bila pertambangan kemudian dilihat sebagai leading sector.

Pada titik ini dapat disimpulkan bahwa dengan 82 Surat Kuasa Pertambangan (SKP) akan mengubah tatanan ekologi yang selama ini ada, malah membawa malapetaka. Anggapan bahwa mangan selalu ada di kawasan gersang dan tanah liat yang selama ini tidak dimanfaatkan untuk pertaniaan adalah rasionalisasi pembenaran atas aktivitas perusakan bentangan alam. Oleh karena itu, dengan 82 Surat Kuasa Pertambangan bisa dibayangkan berapa luas bentangan alam yang dirusakan. Alasan, uang jaminan 50 juta per titik adalah bentuk pelumasan hati warga agar rakyat bisa membenarkan dan menyepakati kebijakan ini.

Siapa yang bertanggung jawab atas kerusakan bentangan alam di Kabupaten TTU? Pertambangan: Industri Rakus Air

Air adalah unsur hakiki untuk bertahannya hidup manusia dan tanaman dan hewan yang tengah bertumbuh kembang. Beberapa dasawarsa lalu persoalan air adalah persoalan wilayah perkotaan, sebab di sana banyak kawasan industri, sehingga banyak lahan dikonsersi menjadi lahan penduduk. Sekarang kelangkaan air telah menggejala di dunia tanpa mengenal sekat-sekat wilayah. Bahwa di banyak wilayah pedesaan, permukaan air bawah tanah jauh menurun, mata air- mata air tercemar dan persediaan menurun secara drastis seiring dengan gencarnya eksploitasi sumber daya alam besar-besaran. Persaingan atas sumber daya air diantara para pemanfaat irigasi, pemilik industri dan konsumen rumah tangga acapkali menguntungkan para penguasa, sehingga menelantarkan masyarakat yang kurang berdaya.

Menghadapi permasalahan krisis air yang terus meningkat dari waktu ke waktu, banyak argumentasi yang dilontarkan. Misalnya: Pertama, kekurangan air akibat penduduk yang semakin bertambah. Kedua, pembagian, pemborosan dan kurangnya penghormatan terhadap air di tengah masyarakat yang materialistis dan konsumeristis. Ketiga, krisis air berkenaan dengan privatisasi pelayanan pasokan air dan kepemilikan atasnya.

Dari beberapa pandangan di atas, dalam konteks Kabupaten TTU dapat ditemukan bahwa beberapa wilayah menjadi pelanggan kekurangan air atau bahkan ketiadaan air. Pada musim kemarau masyarakat harus pergi mencari air untuk minum, mandi, cuci dan berbagai kebutuhan lainnya.

Secara teoritis ataupun empirik, ketersedian air sangat bergantung pada luas hutan dimana berfungsi sebagai water cathcman area (kawasan penangkapan air). Kabupaten TTU memiliki luas hutan seluas 126,235 ha (47,3%) dari luas wilayah daratan. Itu berarti, Kabupaten TTU memiliki kawasan penyangga yang cukup bagus. Dengan hingar-bingarnya 82 Surat Kuasa Pertambangan mangan tentunya akan berdampak pada kerusakan hutan. Pertambangan mangan yang dilakukan di luar kawasan hutan pun akan sangat mengganggu ekologi karena tentunya akan menimbulkan pencemaran udara dan air. Mumpung, belum

dilakukan proses pencucian dan pemurnian mangan dilakukan di wilayah kabupaten TTU. Hal ini akan sangat terasa ketika penggalian, pencucian dan pemurnian dilakukan di wilayah TTU. Lebih dari itu dapat dibayangkan bahwa dengan 82 Surat Kuasa Pertambangan, mengindikasikan bahwa Kabupaten TTU akan mengalami krisis air. Sebelum ada tambang, air menjadi langka. Apalagi ada tambang mangan yang merusak tatanan hidrologi.

Pertambangan Menyebabkan Limbah Beracun/Tailing Tailing adalah satu jenis limbah yang dihasilkan oleh kegiatan pertambangan. Selain tailing, kegiatan tambang juga menghasilkan limbah lain seperti: limbah kemasan bahan kimia dan limbah domestik. Tailing menyerupai lumpur kental, pekat, asam dan mengandung logam. Logam berat itu berbahaya bagi keselamatan makhluk hidup. Pertambangan skala besar biasanya menggunakan bahan kimia seperti sianida, merkuri dan xanthat untuk memisahkan mineral dari batuan. Emisi beracun (limbah berbentuk gas) berupa timbal, merkuri dan sianida, senya sian (CN) kalau dikonsumsi tubuh akan mengganggu fungsi otak, jantung, menghambat jaringan pernapasan, sehingga terjadi asphyxia orang menjadi seperti tercekik dan cepat diikuti oleh kematian.

Kabupaten TTU merupakan wilayah yang cocok untuk pengembangan ternak. Dari data BPS TTU dilihat bahwa peternakan di kabupaten TTU terus mengalami peningkatan dari tahun ke tahun. Misalnya, pengembangbiakan ternak sapi dari 70.229 (2005) meningkat menjadi 75. 475 (2006) (lihat: Timor Tengah Utara dalam Angka 2006/2007, BPS TTU dan BAPEDA TTU). Artinya, ternak sapi sangat cocok dikembangkan di Kabupaten TTU yang selama ini juga menjadi pendapat alternative rakyat dalam memenuhi hak-hak dasar seperti; pangan, pendidikan, kesehatan, pekerjaan dan perumahan yang layak. Pengembangan ternak (sapi, kerbau, kambing dan babi) berkontribusi riil bagi peningkatan kualitas hidup rakyat tanpa merusak. Sedangkan, penambangan mangan di Kabupaten TTU akan berpengaruh pada sumber-sumber penghidupan rakyat (lahan, air, ternak dll) di wilayah ini akan tercemar oleh tailing. Apalagi mangan itu, bila diserap tubuh terlalu banyak akan merusak hati, membuat iritasi, karsinogen atau menyebabkan kanker. Hal ini diperparah karena masyarakat melakukan penambangan mangan tanpa dilengkapi dengan masker dan kaos tangan. Tidak heran para penambang akan perlahan-lahan mengalami keracunan. Penambang sedang bunuh diri dan membunuh anak cucu.

Dengan 82 Surat Kuasa Pertambangan (SKP) di Kabupaten TTU berapa jumlah masyarakat yang diracuni setiap hari dan terancam keselamatannya? Berapa racun yang disebarkan pada lahan pertanian dan peternakan? Apakah pendapatan dari harga mangan 1000-1500/kg melebihi pendapatan pertanian, peternakan dan perkebunan? Bila argumentasinya adalah peningkatan Pendapatan Asli Daerah (PAD), berapa masyarakat Kabupaten TTU yang mengetahui dan mengontrol PAD Kabupaten TTU, sehingga dapat diketahui bahwa Pertambangan Mangan akan meningkatkan PAD.

Dampak Sosial-Budaya Dalam “The Forms of Capital” kontrol dalam kehidupan sosial. (1986), Piere Boudieu membagi modal menjadi kapital budaya dan modal sosial. Modal sosial dapat diterjemahkan sebagai hubungan atau jaringan (network) antara orang-orang yang memiliki pikiran dan gagasan sama tentang suatu hal. Dalam konteks budaya masyarakat Kabupaten TTU, bahwa hubungan sosial (social communal) terbentuk karena kesamaan kepentingan atas pengelolaan sumber-sumber produksi setempat, kesamaan atas tanah dan kekayaan alam, serta kesamaan sejarah dan adat budaya. Direnggutnya penguasaan masyarakat atas tanah dan kekayaan alam menyebabkan fondasi modal sosial mereka lenyap dan berdampak pada: Pertama, lenyapnya daya ingat sosial, hilangnya tatanan nilai sosial yang dulunya dimiliki komunitas. Budaya nekaf mese ansaof mese akan ditinggalkan akibat perebutan mineral (mangan) sebagai pilihan alternatif dalam menunjang kualitas hidup rakyat: Talas/banu (larangan untuk alam yang sementara utuh dan tidak boleh dirusakkan oleh siapa pun); fuatono (ritual adat untuk minta hujan, paska musim kemarau; pembukaan lahan pertanian yang dilandasi dengan adat; ritus adat kepada Faut Kanaf, Oe Kanaf masih dipertahankan; Sek Hau Nomate (untuk panggil lebah dan panen lebah); mengenal pembagian Suf yang sudah ada ketentuan sejak awal oleh leluhur; mempertahankan dan mengenal tempat ritual adat dari masing-masing suku. Kedua, putusnya hubungan silahturami antar warga menyebabkan perpecahan, persengketaan bahkan konflik (saling melenyapkan eksistensi satu sama lain). Mekanisme resolusi konflik tradisional yang telah hidup dalam komunitas tidak dijadikan kontrol dalam kehidupa sosial. Padahal, dalam konteks masyarakat modal menjadi modal kapital, modal Kabupaten TTU, untuk menaati ketentuan hukum adat (banu) yang tidak tertulis biasanya diberi sangsi seperti: Oni (Suni); Satwa (tanduk, kepala babi, bulu); Nuta (Api); Nono hau ana (Hau No’); Opat (denda biasanya disepakati bersama warga).

Dampak Kesehatan Apabila mangan itu diserap tubuh terlalu banyak ia sanggup merusak hati, membuat iritasi, karsinogen atau menyebabkan kanker atau menurunnya daya tahan tubuh, karena merosotnya mutu kesehatan, mental warga, dan seringkali munculnya penyakit- penyakit baru, baik penyakit yang berupa metabolisme akut akibat pencemaran (udara, air, tanah dan bahan-bahan hayati yang dikonsumsi), penyakit menular (kelamin)dan penyakit lain yang dibawa oleh pekerja yang berasal dari luar daerah.

Di Kabupaten TTU, jumlah penderita rawat jalan pada Puskesmas, Puskesmas Pembantu dan RSUD Kefamenanu selama 2006 sebanyak 17248 kali kunjungan (pasien) atau turun 11,8% dibanding tahun 2005 (19568). Jenis penyakit yang dominan masing-masing: Infeksi saluran pernapasan Akut (ISPA) 50,8 %, penyakit lainnya 29,6%, penyakit dengan tanda gejala tak jelas lainnya 6,3%, penyakit yang lainnya di bawah 5%. Sedangkan Penderita rawat inap selama tahun 2006 pada RSUD Kefamenanu sebanyak 2. 267 kunjungan (pasien) atau turun 38,3 persen dari keadaan tahun sebelumnya. Penyakit dominan untuk

kunjungan rawat inap: Diare 34,7% penyakit lainnya sebesar 24,6 %, pneumonia 11,5%, penyakit dengan tanda gejala dan keadaan tak jelas 5,69%, malaria 5,43%, penyakit lainnya dibawah 5% (lihat: Timor Tengah Utara dalam Angka 2006/2007, BPS TTU dan (TTU).

Dari data itu, dapat dianalisis bahwa pertambangan mangan yang dilakukan secara manual di Kabupaten TTU akan berakibat: Pertama, dengan 82 SKP akan memperparah kondisi kesehatan masyarakat Kabupaten TTU akibat tercemarnya lahan pertanian, sumber air dan peternakan. Sebelum adanya pertambangan mangan di Kabupaten TTU, penyakit dominan yang dialami adalah ISPA (Infeksi memperburuk kondisi kesehatan masyarakat kabupaten TTU. Kedua, mempersulit penanganan kesehatan akibat penambangan dengan 82 SKP, karena hampir dilakukan hampir di seluruh wilayah kabupaten TTU. Artinya bahwa pencemaran ini akan dialami daerah yang memiliki potensi pertambangan (tidak terkonsentrasi) pada wilayah tertentu. Kondisi ini diperparah karena Dinas Kesehatan Saluran Pernapasan Akut) dan diare akan mengalami peningkatan yang luar biasa, karena tercemarnya udara, air dan lahan pertanian. Sebelum pertambangan, data BPS (2006) menunjukkan dari 236.853 balita, 142. 535 dalam keadaan baik gizinya, 78.883 mengalami gizi sedang dan 15.435 mengalami gizi buruk. Kondisi ini akan diperparah lagi. Jumlah balita yang mengalami gizi buruk ini akan mengalami peningkatan karena ibu hamil dan anak juga ikut dalam pertambangan mangan. Apalagi, kedua penyakit ini memiliki korelasi dengan pencemaran udara dan air. Untuk itu, pencemaran udara dan air akibat pertambangan mangan akan sendiri tidak memiliki rekomendasi layak tidaknya pertambangan. Dinas Kesehatan bukan pemadam kebakaran tetapi mestinya sebelum pertambangan Dinas Kesehatan sudah memiliki Kajian tentang dampat Pertambangan bagi kesehatan masyarakat. Selama Agustus 2009–Mei 2010 tercatat 12 korban jiwa akibat tertimbun tanah penggalian mangan. Sedangkan di Kabupaten TTU tercatat 4 korban mangan.

Dalam konteks Perlindungan Hak Asasi Manusia (HAM), negara bertanggung jawab atas korban jiwa akibat pertambangan. Itu bukan dilihat sebagai konsekuensi dari pertambangan yang harus ditanggung penambang. Karena tugas Negara adalah melindungi, memenuhi, menghormati serta memajukan hak-hak rakyat.

Tabel Korban Mangan (Sesuai dengan Pemberitaan Pos Kupang)

No. HARI /TANGGAL NAMA USIA (thn) KEJADIAN LOKASI1. 17 Agust. 2009, Daud Lomi Pita (48), Tewas tertimbun galian mangan - RT 22 / RW 06 Dusun C, Desa Tubuhue, Kec. Amanuban Barat, TTS2. 02/10/09, Simon Linsini, Etri Linsini Tewas tertimbun tanah saat sedang menggali mangan - Kel. Naioni3. 06/10/09, Melianus Bariut (51), Petrus Sabloit (38), Ambrosius Seran (11),

Marice (38), Tewas tertimbun saat sedang menggali mangan - Kiumabun, Desa Oebola Dalam, Kec. Fatuleu, Kab. Kupang4. 18 oktober 2009, • Klara Abuk(50) • Hans (30), Tewas Tetimbun tanah ketika sedang menggali batu mangan - Tuataun, Kec.Feoana, TTS5. 1 Desember 2009, Agustinus Sila (30) Tewas mengenaskan dalam lubang tambang mangan - RT 09, Lingkungan 2, Kel.Oelami, Kec. Bikomi Selatan, TTU, Tempat penggalian mangan, Fatukoko6. 1 Desember 2009, Timotius Sali Lisu (29) Ditemukan sekarat dilubang galian mangan, dan harus mnjalani perawatan intensif di RSU Kefamenanu - Kel. Oelami, Kec.Bikomi Selatan, TTU, Tempat penggalian mangan, Fatukoko7. 27 Februari 2010, Marsel Amnesi (30) Tewas tertimbun tanah dilokasi penggalian mangan - RT 20 / RW 2, Naioni,Kupang (Lokasi penggalian mangan Oelnunfafi, kel. Naioni, Kec. Alak,Kota Kupang)8. 5 Mei 2010, Remon Aklili (8) Tewas tertimbun bongkahan tanah saat menggali batu mangan - Murid kelas 2, SDI Oelusapi, dusun 3, Desa Poto,Kec. Fatuleu BaratDita Nono (38) Tewas di tempat Penggalian Mangan - Desa Nimasi, Kecamatan Kab. TTU01/10/10 Martinus Tasik, Maria Bita Luan Tertimbun longsoran tanah akibat penggalian Mangan Tabean B, Desa Tukuneno Kecamatan Tasifeto Barat, Kab. BeluSumber Pos Kupang

Dari data korban mangan (tabel) dilihat bahwa pertambangan mangan bukan hanya berdampak pada buruknya kesehatan tetapi bahkan membawa korban jiwa. Itu berarti tugas negara belum secara maksimal dijalankan. Data Pos Kupang di wilayah Kabupaten TTU telah terdapat 4 korban jiwa. Itu berarti ada preseden buruk dari pertambangan yang katanya membawa kesejahteraan bagi rakyat TTU.

Dampak Ekonomi Ekonomi dibagi menjadi kegiatan Produksi, Distribusi dan Konsumsi. Daya rusak tambang pada ekonomi setempat, merupakan penghancuran pada tata produksi, distribusi dan konsumsi lokal. Pertama, rusaknya tata produksi. Kabupaten TTU merupakan daerah yang cocok untuk pengembangan peternakan selain pertanian. Apabila Pemerintah kabupaten TTU pro-rakyat maka yang didorong adalah pengembangan pertanian lahan kering dan pengembangan peternakan. Ini didukung dengan kondisi wilayah TTU.

Operasi pertambangan mangan dengan 82 SKP di Kabupaten TTU membutuhkan lahan yang luas, dipenuhi dengan cara menggusur tanah milik dan wilayah kelola rakyat. Kehilangan sumber produksi (tanah dan kekayaan alam) melumpuhkan kemampuan masyarakat setempat menghasilkan barang-barang dan kebutuhan pangan.

Pertambangan mangan akan mempersempit lahan pertanian dan peternakan yang selama ini menjadi sumber penghidupan masyarakat TTU. Misalnya,

pengembangbiakan ternak sapi 70.229 (2005) meningkat menjadi 75. 475 (2006) (lihat: Timor Tengah Utara dalam Angka 2006/2007, BPS TTU dan BAPEDA TTU). Artinya, ternak sapi sangat cocok dikembangkan di Kabupaten TTU yang selama ini juga menjadi pendapatan alternatif rakyat dalam memenuhi hak-hak dasar seperti pendidikan, kesehatan dan perumahan. Kedua, rusaknya tata konsumsi.

Lumpuhnya tata produksi menjadikan masyarakat makin tergantung pada barang dan jasa dari luar. Untuk kebutuhan sehari-hari mereka semakin lebih jauh dalam jeratan ekonomi. Uang tunai yang cendrung melihat tanah dan kekayaan alam sebagai faktor produksi dan bisa ditukar dengan sejumlah uang tidak lebih. Bahwa masyarakat kabupaten TTU yang memiliki tata konsumsi yang sosialis, artinya antar warga saling membahu dalam kesulitan. Kondisi ini akan mengalami pergeseran akibat masuknya tambang mangan.

Pertambangan mangan akan membawa perubahan pola konsumsi yang individualistik dan konsumeristik. Lebih dari itu, masyarakat akan sangat bergantung pada pada pasokan pangan dari luar. Ketiga, rusaknya tata distribusi. Kegiatan distribusi setempat semakin didominasi oleh arus masuknya barang dan jasa ke dalam komunitas. Padahal, biasanya pada awal sebuah proses pertambangan akan dibangun opini publik bahwa pertambangan akan membawa kesejahteraan dengan meningkatkan pendapatan ekonomi masyarakat setempat. Namun, seperti yang terjadi di berbagai tempat lain, janji investor dan Pemerintah Kabupaten TTU adalah peningkatan ekonomi rakyat akan berubah roman menjadi kuli di negeri sendiri, seperti yang terjadi pada Pertambangan Buyat Minahasa Raya dimana warga harus meniggalkan tempat kelahirannya karena tidak mampu menanggung derita dampak pertambangan. Karena itu, Pertambangan Mangan di Kabupaten TTU perlu dikaji secara cermat oleh Pemerintah kabupaten TTU. Bukan dengan pragmatis pertambangan disetujui dan diakhiri dengan kekesalan. Permasalahan pertambangan mangan di Kabupaten TTU bukan hanya diperdebatkan soal harga mangan tetapi yang perlu dilihat adalah keberlanjutan wilayah dan potensi TTU bagi anak cucu. Bila tidak pertambangan mangan akan merusak lingkungan dan generasi penerus TTU.

Dampak Politik Politik seringkali diartikan sebagai proses pembuatan keputusan dalam sebuah kelompok. Menurut Dickerson dan Flanagan, politik sebagai “sebuah proses resolusi konflik (kepentingan), dimana segala daya dan usaha dikerahkan untuk pencapaian tujuan bersama”. Kenyataannya, ia berwujud upaya seseorang atau sekelompok orang untuk mencapai tujuannya dengan berbagai cara, bisa mempengaruhi dan meyakinkan, membohongi atau bahkan menyingkirkan pihak lain. Sedangkan menurut Harold Lasswell, politik adalah “siapa mendapatkan apa, kapan, dimana dan bagaimana?”

Dalam konteks politik dapat dibenarkan pendapat Dickerson, Flanagan dan Harold Lasswell, dimana pemimpin Kabupaten TTU memengaruhi dan meyakinkan masyarakat bahwa potensi mangan menjadi pilihan alternatif tanpa menginformasikan dampak buruknya. Rakyat menambang tanpa mengerti apa dampak dari pertambangan mangan. karena tidak mampu menanggung Politik menjadi sasaran daya rusak derita dampak pertambangan. untuk memenangkan kepentingan industri tambang.

Ini dapat dilihat dari beberapa indikasi:Pertama, margininalisasi tata- Kabupaten TTU. Bukan dengan kepemimpinan yang membela pragmatis pertambangan disetujui kepentingan warga oleh negara dan korporasi. Ini bisa dilakukan dengan mendorong penggunaan perangkat-perangkat kepemimpinan formal yang harus patuh kepada ketentuan Negara. Argumentasi Pemerintah yang diwakili Dinas Pertambangan Kabupaten TTU bahwa ada jaminan tiap titik 50 juta. Itu berarti dari 82 SKP, Pemkab TTU memiliki pemasukan dari bidang pertambangan sebanyak 4,1 miliyard. Sedangkan bila didistribusikan pada titik tambang maka tidak ada artinya dibanding kerusakan yang ditimbulkan. Dana itu bila diperlukan untuk rabat jalan dusun pada sebuah desa juga tidak cukup.

Argumentasi ini dinilai sebagai rasionalisasi pembenaran atas pertambangan. Padahal, pemerintah yang baik, perlu menginformasikan tentang kerusakan yang ditimbulkan sehingga rakyat mengetahui resiko baik bagi manusia, lingkungan, sosial budaya. Dan bila perlu sudah bisa diprediksi tentang kerusakan yang ditimbulkan dan apa dana itu mampu untuk merehabilitasi kerusakan yang terjadi. Apakah Pemerintah Kabupaten TTU pernah mendiskusikan rencana pertambangan itu dengan rakyat ataukah ini diambil sebagai inisiasi peningkatan Pendapatan Asli Daerah (PAD). Apakah sudah diperhitungkan dengan berapa besar dana rehabilitasi yang dibutuhkan?

Kedua, rontoknya kelembagaan politik setempat digantikan oleh tata kelembagaan yang patuh kepada aturan-aturan negara. Ini menyebabkan lenyapnya ruang aspirasi dan partisipasi warga, dalam pengambilan keputusan politik setempat. Proses politik menjadi ajang legitimasi sosial bagi operasi tambang di tanah-tanah milik dan wilayah kelola warga. DPRD Kabupaten TTU telah membentuk Pansus Mangan. Apakah Pansus ini memiliki kekuatan dalam menyikapi pertambangan di kabupaten TTU? Kekuatiran yang terbersit adalah adanya kompromi kepentingan antara kekuasaan, DPRD dan investor. Bila ini terjadi maka masyarakat TTU akan mengalami permasalahan yang bersentuhan dengan berbagai aspek kehidupan.

Ketiga, program Community Development adalah cara yang digunakan untuk menggusur kelembagaan politik setempet. Ini biasanya dipakai jaringan LSM/ NGO makanya banyak NGO tidak banyak berkomentar tentang pertambangan atau kerusakan lingkungan hidup. LSM model ini biasanya sangat akrab dengan birokrat dan sangat kompromistis. Sejauh pantauan, dapat dilihat bahwa

kelompok civil society yang mestinya dimotori oleh LSM/NGO di Kabupaten TTU itu tidak dilakukan.

Kesimpulan

Akselerasi pembangunan melalui pengelolaan sumber daya alam terutama melalui bidang pertambangan sebagai jawaban untuk peningkatan Pendapatan Asli Daerah (PAD), penyedian lapangan kerja, percepatan pertumbuhan ekonomi, percepatan pembangunan desa tertinggal atau pengurangan kemiskinan di kabupaten TTU perlu dicermati. Para pelaku pertambangan juga selalu memberikan ilusi-ilusi tentang kemakmuran dan kesejahteraan dari eksploitasi kekayaan alam yang dikeruk dari bumi Indonesia umumnya dan Kabupaten TTU pada khususnya adalah mantera yang digulirkan terus-menerus untuk menghegemoni rakyat bahwa kehadiran industri tambang mangan mutlak diperlukan.

Dari kenyataan yang ada, belum pernah ada bukti. Tambang Emas Freeport di Papua hanya bisa dibanggakan Indonesia sebagai Tambang Emas terbesar tetapi hasilnya adalah Propinsi Papua menjadi propinsi termiskin. Atau tambang Buyat Minahasa, masyarakat setempat harus melepastinggalkan tanah warisan leluhur karena tidak mampu menanggung derita akibat pertambangan.

Prinsipnya, pertambangan merusak sistem hidrologi tanah sekitarnya melalui penggalian. Masyarakat hanya akan menjadi penikmat warisan jutaan ton limbah tambang dan kerusakan lingkungan dan sosial lainnya. Apalagi dicermati bahwa lingkungan hidup di NTT diambang kegentingan akibat pemanasan global, global warming dan perubahan iklim, climate change yang terus terjadi.

Apabila kondisi ini tidak disikapi secara objektif, baik oleh pemerintah maupun masyarakat TTU, tidak heran wilayah ini akan mengalami kondisi yang mengenaskan. Pertama, bumi Biinmaffo berada di antara tiga lempeng yaitu lempeng Indo-Australia, lempeng pasifik Pan lempeng Eurosia. Karena letak ini, maka tak heran wilayah ini sering terjadi bencana. Kedua, bumi Biinmaffo berada di Pulau Timor yang merupakan gugus pulau kecil karena itu sangat rentan dengan kehilangan pulau. Ketiga, bumi Binmaffo tidak hanya bisa dibangun dengan pertambangan. Kabupaten TTU bisa membangun dengan potensi alam dalam bidang pertanian dan kelautan yang terkandung di dalamnya. Keempat, bumi Biinmaffo harus dikembalikan keasriannya dengan menolak seluruh pertambangan yang sedang diproses, karena pertambangan akan menghancurkan ekosistem yang ada di Kabupaten TTU. ***

Manganese Mines Harm Children's Mental Development - Minería del manganeso daña inteligencia de niñosPublished Date: 13-01-2009 Source: Diego Cevallos, Tierramérica Source Date: 26-12-2008

MEXICO CITY - The Mexican mining company Autlán maintains that there is no evidence that manganese causes any harm to human health. But in the central state of Hidalgo, where the metal is mined, adults shake as if they suffered from Parkinson's disease and children's mental development lags behind normal.

"The company takes a sceptical position (about studies that show the effects of manganese poisoning); it does not believe that it is causing the problems or that it is to blame," but the evidence is irrefutable, Horacio Riojas, from the Population Health Research Centre of the government's National Public Health Institute (INSP), told Tierramérica.

INSP studies in areas near the Autlán deposits, distributed among the towns of Molango, Lolotla, Xochicoatlán and Tlanchinol, which together cover some 1,000 square kilometres and are home to just over 60,000 inhabitants, show that the manganese that has been mined there for decades has caused severe harm to human health. The region is one of the world's main storehouses of this mineral, used in the steel industry, as well as in production of chemical products, glass, batteries, fertilisers and medications.

With Riojas at the head of an interdisciplinary group that included the government's National Institute of Neurology, the INSP over the past decade measured the presence of manganese in the air, water supplies, soil, homes and roads near the mines, which are both open-pit and underground operations.

In 2002 and 2003, blood and hair samples were taken from 300 adults and subjected to a variety of medical tests. In 2007, the same studies were carried out for 300 children between the ages of seven and 11. One part of the samples came from residents of areas near the mines, and the rest from residents of places similar in terms of social and economic development, but not near manganese mines.

Riojas said the findings are alarming. Sixty percent of the adults who live near the mines present neurological problems and trembling similar to the effects of Parkinson's disease. In the case of the children near the mines, it was found that their intellectual and learning abilities are 20 percent lower than the comparable group that does not live near any mines.

There is no doubt that the exposure to manganese is the cause of the problems, he said.Autlán began to mine for manganese in the area in 1960.

"We've had reports about problems, but my understanding was that the mining company had already assumed some commitments with the residents and that everything was fine now," Alejandro Dionisio, municipal secretary of Molango, one of the affected towns, told Tierramérica.

In a telephone interview, the official said the mining company provides employment and supports local families with housing infrastructure.

Tierramérica was insistent in its efforts to contact spokespersons from the company for interviews about the situation and the company's relationships with the local communities, but had not obtained a response by the time this report was published. According to Riojas, some residents of the company's area of direct influence -- a 50-sq-km zone shared by Molango, Lolotla, Xochicoatlán and Tlanchinol -- have staged regular protests about health problems and low farm yields, which they blame on manganese mining.

But the demands dissipated when the company built sports fields and school infrastructure and distributed materials for roofing, said Riojas.

Furthermore, exposure to manganese has taken a back seat to other problems arising from the poverty of the local population, he added.

According to official studies, the level of social marginalisation is relatively high in the municipalities where Autlán operates.

Most of the INSP research results were released in early December at an international meeting on the environment andhealth organised by the International Development Research Centre (IDRC) in Mérida in southeastern Mexico.

Authorities in Hidalgo and the federal government of conservative President Felipe Calderón, as well as the company itself, are aware of the studies and their results. Riojas said officials are familiar with the research and that there is a negotiation panel to define what measures to adopt, but he said they are not acting with the urgency required.

Between January and September, Autlán reported 315 million dollars in earnings. On its web site there are no references to the manganese-related health problems.

A text on the site states that unnamed international institutions have declared that they know of no cases in which manganese has caused environmental damage and, on the contrary, there are publications about the beneficial effects of manganese for soil.

Manganese is an element that is found in dried fruits, cereals and legumes. Ingestion of small amounts is essential to maintaining strong bones, the proper functioning of the nervous system and the metabolism of carbohydrates.

But excessive exposure causes an illness known as manganism. The symptoms include: slower movement and lack of coordination, trembling similar to Parkinson's, muscular weakness and even schizophrenia, according to the World Health Organisation.

The INSP has not studied the health of the mine workers, because "it has not been part of the project and we know it would be unlikely that the company would allow it," said Riojas.The studies began to be carried out in 1999 in the mining zone, at the request of authorities who had received complaints from local residents.

The company has taken some steps in the past 10 years, including several recommended by the INSP, such as not using the mine waste as fill for roads, and modifying some of the machinery to reduce emissions of manganese.Even so, the studies indicate that the local population remains affected by the mining. The

INSP is proposing norms that establish obligatory limits of manganese emissions -- no such standards exist today in Mexico -- and ongoing monitoring to ensure compliance.

"At no time have we proposed that the mine shut down its operations, nor have the local residents, but we want production to be clean and safe," said Riojas. If no major decisions are made about the Hidalgo manganese pollution in the first few months of 2009, the case will be presented to the National Health Council, which comprises the health secretaries of the country's 32 states and the federal health minister.

Autlán, which employs 1,400 people, states on its web site that it has been "decisive and constant" in its environmental efforts and that evidence of this was "the ISO 14.000 certification of all of the company's units and plants since 1998."

ISO (International Standardisation Organisation) 14.000 establishes parameters for environmental management that companies can adopt in order to be certified.

Manganese Side EffectsBy Yvette Davis, eHow Contributor

Manganese is a mineral that is used by the body for bone formation, protein metabolism, energy production and other functions. Most people's bodies contain approximately 15 to 20 mg of manganese, roughly half of which is in the bones. The remaining 50 percent is concentrated in the kidneys, liver, pancreas, adrenal and pituitary glands. Manganese from foods or supplements is never toxic, but there are reported lung problems from inhaled manganese dust from mining, battery making and welding.

Dietary Needs1. There is no recommended daily allowance for manganese, however, the National

Academy of Sciences has stipulated adequate intake (AI) levels and tolerable upper limit (TUL) levels for the mineral. Those values are as follows:

AI TULInfants 0-6mo 3 mcg prohibit supplements, no food guidelines

Infants 7-12 mo 600 mcg prohibit supplements, no food guidelines

Children 1-3 yrs 1.2 mg 2 mgChildren 4-8 yrs 1.5 mg 3 mg

Males 9-13 yrs 1.9 mg 6 mgMales 14-18 yrs 2.2 mg 6 mgMales 19 & up 2.3 mg 11 mg

Females 9-18 yrs 1.6 mg 6 mgFemales 19 & up 1.8 mg 11 mgnot pregnant or lactating

Females 2.0 mg 9 mg Pregnant or Lactating

Functions of Manganese in the Human Body2. Manganese helps the body use several of the B-vitamins, choline and vitamin C

by activating the enzymes needed for processing those molecules. Manganese is also responsible for activating the enzymes, which are involved in the development of healthy bones. Manganese helps metabolize glucose, form urea and, according to Staying Healthy with Nutrition by Elson Haas, M.D., also may help protect cell membranes and the nerve coverings by acting as a protective antioxidant. It is thought that manganese also plays a role in the production of thyroxine, a chemical that is vital to the health of the thyroid

Signs of Deficiency3. Deficiency of manganese can manifest itself in several ways. Children with a

severe deficiency of this mineral may experience seizures, blindness or may become paralyzed.

Adults deficient in manganese can have hearing disturbances, such as hearing odd noises that aren't there. They may also suffer from dizzy spells or weakness. Other possible signs of low manganese include weight loss, irregular heartbeat or a decreased glucose tolerance.

According to Haas, manganese deficiency in rats has been linked to sterility, a decrease in bone growth and health, poor brain function and decreased threshold for seizures. It is unsure what these results in rats means for humans.

Symptoms of Toxicity4. Although manganese toxicity is rare when the mineral is obtained solely from

food sources, those who are exposed to the dust from manganese mine are susceptible. In countries where manganese is mined, such as Chile, it is well documented that an overdose of inhaled manganese can cause symptoms including weakness, anorexia, mania, insomnia, delusions and even hallucinations. Some people also experience symptoms of muscle rigidity, or tremors, similar to Parkinson's disease. This condition is treated by stopping the exposure to inhaled manganese and by giving the victim L-dopa, which converts to dopamine in the brain.

A second source of manganese toxicity is through drinking water. It has been determined that manganese in drinking water at amounts more than 2 mg per liter of water can lead to problems similar to those from the inhaled mineral.

The Best Food Sources5. Manganese in levels that promote optimal health can be found in whole grains

and nuts. Legumes, seeds, alfalfa and leafy greens such as spinach are also good sources.

"Nutritional Herbology" by Mark Pedersen says that red raspberry leaves contain almost two times more manganese than any other herb, with 14.60 mg per 100 g of the leaf. This makes red raspberry leaf an excellent source of the mineral for those who use this herb.

Read more: Manganese Side Effects | eHow.com http://www.ehow.com/about_5410572_manganese-side-effects.html#ixzz183bkwpwiUskup Ruteng: Tambang Hancurkan Tatanan Alam

pk/lynMgr. Hubertus Leteng, PrRabu, 4 Agustus 2010 | 09:52 WIB

RUTENG, POS KUPANG.Com -- Gereja Katolik Dioses Ruteng menolak dengan tegas semua kuasa pertambangan di wilayah Manggarai. Kegiatan pertambangan dinilai menghancurkan seluruh tatanan alam.

Uskup Ruteng, Mgr. Hubertus Leteng, Pr, menyampaikan hal itu menjawab Pos Kupang melalui telepon selulernya di Ruteng, Senin (2/8/2010). Dia dimintai pendapatnya usai mengunjungi lokasi pertambangan di Nanga Rawa, Torong Besi dan Serise, belum lama ini.

Menurut dia, alam yang indah terancam keutuhannya oleh perilaku manusia sendiri yang serakah dengan alam. Fakta yang ada di tiga lokasi itu memperlihatkan suatu kondisi yang memprihatinkan. Tatanan lingkungan dan alam sekitar sudah hancur berantakan akibat ulah manusia sendiri. 

Dia menegaskan, alam adalah ciptaan Tuhan yang utuh. Manusia dan alam ciptaan adalah saudara. Karena itu, kita tidak boleh saling menyakiti, apalagi dengan tahu dan mau menghancurkannya.

Dia menjelaskan,  siapa pun tidak berhak mencabut hak hidup ciptaan lain demi uang. Tanah dan alam ini milik semua orang dan ciptaan lainnya. "Apa pun bentuk pertambangan harus ditolak," katanya.

Harus dihentikanSebelumnya, jaringan tokoh agama peduli ekonomi, sosial budaya (Jatab-Ekosob NTT) menyerukan agar wilayah NTT harus bebas dari semua aktivitas pertambangan. Karena itu, kegiatan eksplorasi dan eksploitasi pertambangan yang sedang berlangsung di Kabupaten Belu, TTU, TTS, Kupang, Manggarai dan Manggarai Timur harus dihentikan.

Seruan pastoral itu disampaikan dalam pernyataan sikap yang dibacakan secara bersama-sama di lokasi pertambangan Soga II, Kelurahan Wangkung-Torong Besi, Kecamatan

Reok, Kabupaten Manggarai, Sabtu (10/7/2010).

Pernyataan sikap setebal empat halaman itu ditandatangani oleh Pater Otto Gusti, SVD (STFK Ledalero), Rm. Petrus Kanis Ali, Pr (Paroki Benteng Jawa), Pdt. Yan Leimany (GMIT Ende), Abdul Rajak (Komunitas Muslim Manggarai), Pdt. Linda Kisek (GMIT Kupang), Pdt. Feby Bengu (GMIT Kupang), Pdt. Apliana Rambu Leki (GKS Sumba), Rm. Emanuel F. Kun, Pr (JPIC Keuskupan Atambua), P. Markus Tulu, SVD (JPIC Provinsi SVD Ende), Ir. Abdul Latif (Komunitas Muslim Manggarai). Pdt. Victor Nenohai (GMIT Belu), Dominikus Kase (GMIT TTS), Pater Vinsensius Bili, CSsR (Dekenat Sumba Timur). Pdt. Eritrika A.Nulik (GMIT Semau Kupang), Drs. Vinsensius B. Loe (Yayasan Solidaritas Belu), Pdt. Wisye Makatita (GMIT Manggarai), Rm. Vinsensius K Tena, Pr (PSE Delsos Keuskupan Weetabula), Siti Sarifa (Komunitas Muslim Manggarai Timur), Marthen Roga Ate (Tabloid Sabana Sumba Timur). Rm. Charles R Suwendi (JPIC Keuskupan Ruteng), Pdt. Loth Ba'un (GMIT TTS), Rm. Gregorius S Dudy, Pr (JPIC Keuskupan Atambua), Ronny Malelak (Formasi Sumba Barat), Pater Marsel Nahas, SVD (JPIC Provinsi SVD Ruteng), Pdt. Mel Gerard Th.Messakh (GMIT Kupang), Pdt. Iswardy YS Lay, (Komunitas Tuak Pedis Rote Ndao), Pdt. Yunus Edi W Manu, (GMIT Rote), Siti Rahmah (Komunitas Muslim Manggarai Timur), Pater Mateus Batubara, OFM (JPIC OFM Manggarai).

Menurut mereka,  aktivitas pertambangan telah mengakibatkan longsoran dan hilangnya nyawa terus-menerus. Sementara itu, tidak ada upaya dari pemerintah untuk menghentikan aktivitas tersebut. Masyarakat menderita fisik dalam bentuk sesak nafas, nyeri dada, sakit kulit, batuk berdarah dan berbagai bentuk sakit fisik lainnya yang belum teridentifikasi.

Menurutnya, kualitas kesehatan masyarakat akibat pencemaran udara, air dan suara menurun. Masyarakat kehilangan sumber mata air, hilangnya kesuburan tanah dan hancurnya ekosistem hutan.

Dampak lain pertambangan adalah meningkatkan keterlibatan anak usia sekolah dalam penggalian mangan yang berdampak pada tingginya angka putus sekolah dan risiko kematian pada anak-anak. Munculnya fenomena perbudakan akibat jeratan hutang pada masyarakat lingkar tambang. Munculnya ketegangan sosial dengan kehadiran aparat keamanan dan Satpol PP. Maraknya  perjudian dan prostitusi di  wilayah lingkar tambang. Ancaman krisis pangan dan kelaparan akibat meningkatnya alih fungsi lahan produktif. Masyarakat didorong untuk menjadi pelaku perusakan lingkungan serta diabaikannya kepentingan masyarakat generasi yang akan datang.

Berdasarkan fakta-fakta tersebut, maka Jatap-Eskosob NTT menyerukan penghentian eksplorasi dan eksploitasi pertambangan yang tengah berlangsung di Belu, TTU, TTS, Kupang, Manggarai dan Manggarai Timur.

Bebaskan seluruh wilayah NTT dari aktivitas pertambangan yang destrukstif terhadap kehidupan manusia dan alam. Hentikan pemberian izin pertambangan di kabupaten yang belum terkena aktivitas pertambangan. Mengembangkan alternatif sumber penghidupan

yang berkelanjutan seperti pertanian, perikanan, kehutanan, pariwisata dan industri kecil. Hentikan segala bentuk praktik korupsi yang melahirkan kemiskinan, kebodohan dan kerusakan mental pejabat dan rakyat. Hormati dan lindungi hak-hak masyarakat.

Pantauan Pos Kupang, Sabtu (10/7/2010), anggota rombongan tiba di puncak pertambangan Soga II sekitar pukul 13.30 Wita. Setelah mengamati kondisi lingkungan pertambangan  PT Sumber Jaya Asia yang sudah dihentikan, dilanjutkan dengan doa bersama yang dipimpin Pdt. Loth Baun, S.Th. Pdt. Loth mengajak semua peserta  untuk merenung tentang kekayaan alam yang sudah dikoyakkan manusia. Karena itu tanam pohon kehidupan bukan tambang. Setelah doa bersama dilanjutkan dengan penanam pohon gamal di lokasi tambang. (lyn)

The dangers of manganeseChildren's IQs under threatPublished Date: 04-10-2010 Source: Toronto Sun Source Date: 20-09-2010

Yet another material enters the lexicon of toxic metals and minerals - including mercury, lead and asbestos - that threaten human health, in particular that of children.

Recent findings by the University of Quebec show that excess amounts of manganese, contained in drinking water, can severe reduce a child's Intelligence Quotient (IQ) - even though the levels are below current official limits.

The study apparently does not link  manganese poisoning to releases of the metal from mines into adjacent water bodies.

Yet, as pointed out on this website, there are several recent examples of such occurrences:

See: Gabonese NGO decries effects of mining - pointing to the toxicity created by Comilog's manganese mining in Gabon.

Also: Rio Tinto sued for pollution at "best practice" mine - which refers to the excessive levels of manganese in the Flambeau river watershed, following Rio Tinto's closure of its eponymous mine.

Water containing manganese could lower child's IQ: Study

QMI Agency in Toronto Sun

20 September 2010

Well water with high levels of manganese could lower a child's IQ, a new study from Quebec researchers says.

Looking at 362 Quebec children between the ages of six and 13 who were living in homes supplied by groundwater, researchers found the intelligence quotient (IQ) of children who drank water that contained higher amounts of manganese were six points below children whose water contained little or no manganese.

"This is a very marked effect; few environmental contaminants have shown such a strong correlation with intellectual ability," study co-author Donna Mergler said in a release.

Lead author Maryse Bouchard of the University of Montreal added, "We found significant deficits in the intelligence quotient (IQ) of children exposed to higher concentration of manganese in drinking water. Yet, manganese concentrations were well below current guidelines."

Manganese is commonly found in groundwater, including public and private wells. Health Canada says on its website that it is present in more than 100 "common salts and mineral complexes" found in rocks, soils and and on the floors of lakes and oceans.

"The greatest source of this exposure is from food. Intake from food is substantially higher than intake from drinking water, even in areas where the manganese content of water is high," Health Canada said online.

Health Canada also says manganese is an essential element, and among other things, is used by the body to metabolize carbohydrates. A manganese deficiency in animals has led to the central nervous system not functioning properly. Humans who haven't had enough manganese have developed dermatitis and high blood cholesterol.

While considered one of the least toxic elements, Health Canada said in extreme cases it can lead to "neurological manifestations" and some studies have reported a link to the male reproductive system problems and birth defects.

The study, which appeared Monday in the journal Environmental Health Perspectives, reported the amount of manganese in food "showed no relationship to the children's IQ."

The study said some municipalities where the study was conducted have already installed a filtration system that removes manganese from the water. The authors also said using home filtering pitchers that contain a mixture of resins and activated carbon can reduce the concentration of manganese by 60% to 100%.

Excess manganese stunts child intellect: study

AFP

20 September 2010

MONTREAL - Excess amounts of manganese -- a hard, brittle metal found in some drinking water around the world -- may have adverse effects on children's smarts, Canadian scientists said Monday.

A team of researchers at the University of Quebec in Montreal discovered that children exposed to high concentrations of manganese in drinking water performed worse on tests of intellectual functioning than children with lower exposures.

The results, published in the scientific journal Environmental Health Perspectives, prompted the researchers to urge a review of national and international guidelines for safe levels of manganese in drinking water, and home use of water filtering pitchers to reduce concentrations where it is high.

The study examined 362 children between the ages of six and 13, living in Quebec homes supplied by groundwater. For each child, the researchers measured the concentration of manganese in tap water from their home, as well as iron, copper, lead, zinc, arsenic, magnesium and calcium.

The amount of manganese from both tap water and food was estimated from a questionnaire. Finally, each child was assessed with a battery of tests assessing cognition, motor skills and behavior.

"We found significant deficits in the intelligence quotient (IQ) of children exposed to higher concentration of manganese in drinking water. Yet, manganese concentrations were well below current guidelines," said lead author Maryse Bouchard.

The average IQ of children whose tap water contained the highest manganese concentrations was six points below children whose water contained little or no manganese. Presence of manganese in food had no impact.

"This is a very marked effect," said study co-author Donna Mergler. "Few environmental contaminants have shown such a strong correlation with intellectual ability."

Manganese is naturally occurring in soil and air, and in certain conditions is present in groundwater in naturally high levels. It is also used in stainless steel, alkaline batteries, unleaded gasoline and coins.

2Abbreviations used: ATSDR, Agency for Toxic Substances andDisease Registry, U.S.A.; B-Mn, blood manganese; B-Pb, bloodlead; CAS, Chemical Abstract Series; EPA, Environmental Pro-tection Agency, U.S.A.; LP, lipid peroxidation; MAO, monoamineoxidase; MMT, methylcyclopentadienyl manganese tricarbonyl;Mn, manganese; Mn2#, manganese oxide; MRC, Medical Re-search Council; PM10, particulate matter of less than 10 lm; Si,silica; SO2, sulfur dioxide.1To whom correspondence and reprint requests should beaddressed. Fax: 525-5133151; E-mail: [email protected] Research Section A 85, 90}104 (2001)doi:10.1006/enrs.2000.4108, available online at http://www.idealibrary.com onExposure to Manganese: Health Effects on the General Population,a Pilot Study in Central MexicoCarlos Santos-Burgoa,*,1 Camilo Rios,- Luis Alberto Mercado,? Rodolfo Arechiga-Serrano,?Fernando Cano-Valle,A Rocio Alatorre Eden-Wynter,* Jose Luis Texcalac-Sangrador,*Juan Pablo Villa-Barragan,* Yanneth Rodriguez-Agudelo,- and Sergio Montes-*Instituto de Salud Ambiente y Trabajo, Cerrada del Convento 48-A, Colonia Santa Ursula Xitla, Tlalpan, D.F. c.p. 14420, Mexico;- Instituto Nacional de Neurologia y Neurocirugia, Mexico; ?Secretaria de Salud del Estado de Hidalgo; and AClinica Londres, MexicoReceived January 6, 2000To support a risk assessment of manganese expo-sure in two communities living within a manganesemining district a cross-sectional study was per-formed on a sample of the adult population of long-term residents. One community was exposed toa point source from an ore primary reAning plant.Manganese is an essential mineral for human life. Itis also the fourth in importance for industrial metalmaking. Data were collected on socioeconomic liv-ing conditions, emission sources, environmentalmedia concentrations (air, water, soil, dust, food),respiratory symptomatology, and a neuro-psychological examination (Mini-Mental Screeningtest, the Hooper Visual Organization test, theArdila-Ostroski, and others). We examined 73 sub-jects (52 women), most of low socioeconomic status.Environmental air concentrations were 2 to 3 timeshigher than those in other urban concentrations.Manganese blood concentrations ranged from7.5 to

88 lg/L, with a median concentration of 15, the up-per quartile starting at 20 lg/L; the upper 10% wasabove 25 lg/L. Lead and manganese were highlycorrelated; there was an inverse relation to hemo-globin. Reduced levels of plasma lipid peroxidationwere associated with blood manganese. Usingmultivariate logistic regression, we identiAed B-Mnas increasing the risk of deAcient cognitive perfor-mance 12 times (Mini-Mental score of less than17). ( 2001 Academic PressKey Words: manganese; exposure assessment;cross-sectional; lipid peroxidation; neuropsycho-logic.BACKGROUND AND RATIONALECentral Mexico has one of the largest manganeseMn2ore reserves in the Americas, with 32 milliontons of proven reserves (1), mainly of manganesedioxide. Its commercial extraction was started in1962 in a mining district with several agriculturallybased communities and a very stable population rep-resenting a lifetime exposure to naturally and anthro-pogenically released manganese. Extraction isperformed through both strip and underground min-ing, and primary re7ning is done on site. The localgovernment commissioned a Manganese ExposureRisk Characterization project to address the commun-ity concerns about the ecological impact of miningactivities and their health effects on the population.Manganese (CAS-7439-96-5), found in its naturalstate in the earth’s crust, is an essential mineralimportant to mitochondrial oxidative processes (2).It is a gray metal that blackens when oxidized, andits Mn2# oxidation form is the most bioavailable.Greater absorption happens in acidic media andwith oxidized manganese. Its bioconcentration ishighest in the lower food chain. It is also used innutritional supplements and multivitamin prepara-tions. Its toxicological pro7le is being updated (2).World production has increased by 30-fold through-out this century due to industrial use. Its use is900013-9351/01 $35.00Copyright ( 2001 by Academic PressAll rights of reproduction in any form reserved.widespread and it is the fourth most important min-

eral in the world for industrial metal making (3).Scienti7c concern has arisen due to its widespreaduse in ceramics, the manufacture of matches, glass,soldering, metal alloys, batteries, aluminum cans,electronic components, and, for over 20 years, ingasoline additive compounds such as methylcy-clopentadienyl manganese tricarbonyl (MMT). Thereevaluation of Mn health risks by the EPA in 1994led to the resolution to delay the decision on accept-ing Mn as a gasoline additive in unleaded gasoline,given the lack of better empirical data (4). Chronichuman exposure and effects data, the absorptionef7cacy of the different exposure routes, and theshape of the dose}response;if any;are some of thekey, biologically important questions. The dis-cussions during a recent international symposium(5) highlighted the need for human exposure assess-ment and effect biomarkers studies.For the present study we selected two biomarkersof the biochemical effect of manganese, on the basisof previous studies in manganese-exposed workers:platelet monoamine oxidase activity (MAO) (6) andplasma lipid peroxidation (7). There are also experi-mental reports in animals showing alterations inboth brain and liver mitochondrial activity of MAO(8) and brain lipid peroxidation (9). Consistently, themost important health end point is the neuro-psychologycal, including the cognitive, motor andsensory areas; for this pilot we selected a battery oftests adapted for Mexican rural conditions (10}17)that reliably and practicably could be done on the site.We developed this study in collaborationwith localhealth authorities. The purpose was to gather localexposure and effect information in order to comp-lement the risk assessment. Furthermore, this studyconstituted a 7rst approach to the understanding oflocal health conditions as related to the extractionand primary re7ning of manganese.METHODSWe performed a cross-sectional study of two com-munities in the manganese-mining district. Thesecommunities were selected through a prioritizationalgorithm and consultation with a State Interin-stitutional Commission. Community A was 2 kmfrom the primary ore re7ning plant, residing in theuphill area surrounding the plant; the census data

enumerated 1257 inhabitants. Community B was25 km downhill and downstream from the pointsource; census data enumerated 692 inhabitants.The survey was accomplished throughout themonths of the dry winter season. After dividingCommunity A into four sectors, we obtained a prob-abilistic strati7ed random sample without replace-ment of households and recruited one volunteer perhousehold. Each volunteer was asked for an in-formed consent for his participation. Local medicalservices, including community-based health pro-moters, from the Ministry of Health and the SocialSecurity provided mapping,morbidity and mortalityinformation, and community access and were heav-ily involved in the project.Several instruments were developed, including aninformed consent form, a sociodemographic ques-tionnaire (housing, food intake, occupation, risk per-ception), and a modi7ed Chronic Bronchitisquestionnaire that we adapted and previously tested(18}20) for Mexico from the British MRC question-naire. Standardized and trained personnel appliedthe questionnaires to 46 subjects in CommunityA and 27 subjects in Community B, including a totalof 21 men and 52 women.Neuropsychological ExaminationIn order to address the neuropsychologic evalu-ation, a team of trained psychologists successfullyapplied to 44 and 27 subjects in Communities A (twosubjects failed to perform the tests adequately) andB a test battery. We used the neuropsychologicalscheme (10). It consisted of timed tasks assessingdifferent aspects of motor behavior. It contained 41items that examine hand and bilateral motor speedand coordination, the ability to imitate motor move-ments, symbolic actions, con8ictive reactions, andchoice reactions. The items were scored, according tothe manual, as follows: 0, within the normal range,1, mild impairment, 2, severe impairment. This testwas adapted to Spanish and the normal values werethose described by Ardila and Ostroski (11). TheHooper visual organization test (HVOT) was alsoapplied. The HVOT was developed to identify thosepatients with organic brain conditions in psychiatrichospitals. Thirty or more pictures of readily recog-nizable cut up objectsmake up the test. The subject’s

task is to name each object verbally when the test isindividually administered; the HVOT proved to bevery sensitive to dementia and disease duration inParkinson’s patients (12). The score is the total num-ber of correct answers. Attention and concentrationfunctions were monitored with the Trail MakingTest (13), which assesses visual conceptual and vi-somotor tracking and it is administered in two parts.Trail Making requires the subjects to connect se-quential numbers placed in circles randomly distrib-uted on a plane. Trail making B, which includesEXPOSURE TO MANGANESE 91symbols set shifting, provides a measure of cognitive8exibility and requires the subjects to alternate fromone number to one letter (1-A-2-B-3-C2). The sub-ject is urged to connect the circles ‘‘as fast as youcan,’’ without lifting the pencil from the paper. Thisis a test of complex visual scanning with a motorcomponent. The digit span test, also applied, pro-vided a measure of metal tracking and sustainedattention (14). The subjects are asked to immediate-ly recall a progressively increasing series of digitsread by the examiner (minimum three, maximumnine). The digit span backward requires the subjectto repeat the digits in reverse order (minimum two,maximum eight).Verbal 8uency was measured by the quantity ofwords produced in a restricted category (e.g., ani-mals) or the words according to an initial letter (F, A,S) and usually within a time limit (1 min).Cognitive function was assessed with the Mini-Mental State Examination. This formalized mentalstatus examination is widely used as a brief screen-ing instrument for dementia. Administration takesfrom 5 to 10 min. The standardized administrationand scoring procedures are easily learned. Scoresbelow 17 (adapted for the rural Mexican population)are considered abnormal (15}17). The time taken toadminister the battery was 2.5 h. The same test wasadministered by the same person.Biomarkers and Clinical DataBlood samples of 40 ml were obtained by venouspuncture in 46 and 27 subjects in CommunitiesA and B and after previous skin cleansing followingskin cleansing with a non-ionic detergent and rins-ing with deionized water. The samples were thenrefrigerated before being transported, during trans-

portation, and in the clinical laboratory. Blood wasstored in Vacutainer tubes with EDTA as an an-ticoagulant until assayed (21). Besides bloodmanga-nese (B-Mn), blood lead (B-Pb), and hemoglobin (hb),we used plasma lipid peroxidiation (LP) and mono-amine oxidase (MAO) as early effects biomarkers(7, 22, 23). All sampling materials were prewashedwith 3%nitric acid. A subset of 20 and 12 volunteersfrom communities A and B were taken to a regionalclinic for X-ray examination and classi7ed witheither 7brosis or nodulation or both by a certi7edmedical pulmonary radiologist.Environmental SamplesEnvironmental samples were obtained in the com-munities of each of the following media; wells ata depth of 1.5 to 2 m (n"14); approximately 500 g.of soil samples dug from the bottom of a 0.18-cm3pothole (n"10). Household PM10 was collected for24 h from within the central room of 10 houses.A 5-day, 24-h PM10 outdoor air sample was collectedwith a PM10 High Volume sampler installed at theCommunity A church and on the CommunityB medical unit roof. River samples were obtained inCommunity B, since Community A had no river.Samples were obtained at 7ve different points alongthe river at a depth less than 1 m in order not todisturb the sediment. Limited time and resourcesdid not allow for individual subject personal samp-ling. Individual exposures were assigned by weigh-ing each subject by its home distance to the closermonitoring site.Lead and Manganese in Blood AnalysesBoth lead and manganese in blood were analyzedby graphite furnace atomic absorption spectro-photometer (GFAAS), according to techniquespreviously reported (24, 25). A Perkin}Elmer3110 atomic absorption spectrophotometer and anHGA-600 graphite furnace with AS-60 autosamplerwere used. Calibration curves for lead were con-structed using an aqueous lead reference standard(NBS-3128, NBS Gaithesburg, MD). For manga-nese, curves were constructed with a MerckTitrisol standard solution. Quality control forlead analysis was assessed by our current participa-tion in the lead Wisconsin State Laboratory of Hy-giene pro7ciency program. Analyzing an Eastman-

Kodak gelatin standard material (LabLEADER)consituted the internal quality control for manga-nese.Analysis of Manganese in Food SamplesReady-to-eat food samples were requested ina random subsample of 20 and 12 householdsfrom Communities A and B and refrigerated.Food samples were stored in polypropylene con-tainers that were previously washed with 3% (v/v)HNO3, rinsed with deionized water, and nitrogengas-dried to avoid external contamination. The foodwas homogenized with a food processor with a stain-less steel grinder. A sample of 1 g was carefullyweighed and submitted to acid digestion usingSuprapur (E. Merck) HNO3 in a water bath at 603Cfor 30 min. The clear solution was diluted with de-ionized water, and manganese was analyzed byGFAAS.92 SANTOS-BURGOA ET AL.Platelet Monoamine Oxidase ActivityPlatelets were isolated according to Mustard (21).The activity of monoamine oxidase was obtained bya technique described by Krajl (26), usinga Perkin}Elmer LS100 luminescence spectro-photometer. Isolated platelets were resuspended in780 ll of albumin-free Tirode and 200 ll of this re-suspension was incubated for 1 h at 373C, in a solu-tion containing 250 ll of 0.5 M phosphate buffer (pH7.4)#500 ll of 0.6 M kynuramine#500 ll of water.After incubation, 1 mL of 10% (w/v) trichloroaceticacid was supplemented and samples were centri-fuged at 1500 rpm. Twenty-microliter aliquots fromthe supernatants were supplemented with 1 ml of1 M Na OH. Florescence was determined at 315-nmexcitation and 380-nm emission wavelengths. A cal-ibration curve was constructed using 4-hydro-xyquinoline as a standard. Results were reported asnmol of 4-hydroxyquinoline formation/h/mg of pro-tein.Plasma Lipid PeroxidationPlasma was separated from blood and themonitoring of lipid peroxidation was performed bymeasuring lipid 8uorescent product formation ac-cording to Lunec and Domardy (27), within the 6 hafter sample withdrawal; 500 ll of the plasma sam-ples was separated in a glass tube covered from light

and supplemented with 4 ml of 2:1 (v/v) chloro-form}methanol mixture. Tubes were capped andvortex-mixed for 2 min. The samples were centri-fuged at 10,000 rpm for 10 min and the aqueousphase was discarded; 2.5 ml of the organic phasewere transferred to clean glass tubes and vortexedwith 1 ml of deionized water. Tubes were placed onice for 15 min; 500 ll of the chloroformic phase wastransferred into a quartz cuvette and mixed with0.1 ml of methanol. Fluorescence was measured ina Perkin}Elmer LS50B Fluorescence Spectro-photometer at 370 nm of excitation and 430 nm ofemission. Prior to the measurement of the samples,the sensitivity of the spectrophotometer was ad-justed to 140 8uorescence units with a 0.1 mg/Lquinine standard, prepared in 0.05 M sulfuric acid.Results were expressed as 8uorescence units permilliliter of plasma. All samples were run in duplic-ate.Data Management and AnalysisData formats and questionnaires were checked onsite and coded according to the coding manual iden-ti7cation. Data were entered into a database andtheir management procedures were documented,ready for auditing. Data were analyzed using Stata5.0 software (28), storing all analysis procedure logs.We developed exploratory data analysis in order tocheck data, as well as to transform continuous vari-ables into a near Gaussian distribution to assurenonviolation of assumptions of parametric analysis.When necessary, we used distribution- and refer-ence-independent categorization, dichotomizingeither at the median or with different centiles. Sev-eral indices (from the sociodemographic question-naire) were constructed in order to group covariatesrelated to indoor and outdoor emissions, ventilationand socioeconomic level. The indoor emission indexconsidered all dust-related sources, including woodsmoke, a household with uncovered soil, indoorwater, and area heaters; the outdoor emission indexincluded proximity to the industrial plant, road traf-7c, trash, and industrial residues accumulation. Bi-variate analyses were 7rst done in tabular form,selecting candidate variables for the models; de-pending on the distribution and types of variablestabular data were tested with s2

or using t tests tocompare group means with unequal variances. One-tailed tests were used, as the hypothesis was ofexcess risk from manganese exposure and thereforeused 90%con7dence interval estimation.Multivari-ate modeling was done through least squares linearregression (29) when the dependent variable wascontinuous. We calculated prevalence risk ratiosbased on the regression coef7cients when they wererequired. We built dummy variables for those cat-egorical ones and used robust regression when weobserved distribution restrictions in the covariates.We used logistic regression for dichotomic depen-dent variables and multinomial regression for nom-inal dependent variables. When confronting seriallycorrelated residuals, we used Hildreth}Lu regres-sion (30).RESULTSAs seen in Table 1, most of the study subjects werewomen, housewives within an agricultural commun-ity, and poorly educated. On average they wereadults (ranging from 14 to 93 years of age, 90% ofthem within an age range of 16 to 80 years), long-term residents with poor housing and sanitary con-ditions. Many use lead-glazed pottery for cookingand consume local foods. Both communities are sim-ilar in their socioeconomic and housing conditions,with fewer years of schooling in Community B,where the residents have lived somewhat longerEXPOSURE TO MANGANESE 93TABLE 1Descriptive Statistics of the Study Population CharacteristicsVariable Category Total Community A Community BPopulation size 73 46 27Sex Men 21 14 7Women 52 32 20Occupation Miner 0 0 0Student 1 1 0Agriculture 14 7 7House 48 29 19Laborer 3 3 0Commerce 1 1 0Other 1 1 0Any schooling Yes 377 23 14No 36 23 13Average years 2.15 (SD, 3.03) 2.37 (SD, 3.36) 1.81 (SD, 2.48)Average age 43.35 (SD, 17.43),

range 14 to 9341.43 (SD, 18.36),range 15 to 9346.46 (SD, 15.67),range 14 to 75Average years of residencyat the home19.10 (SD, 16.60),range 1 to 8817.67 (SD, 17.23),range 2 to 8821.58 (SD, 15.46),range 1 to 75Indices Socioeconomic (2}5) 2.57 (SD, 0.80) 2.65 (SD, 0.86) 2.42 (SD, 0.70)Internal emissions (0}4) 1.87 (SD, 0.88) 1.57 (SD, 0.84)* 2.41 (SD, 0.69)External emissions (1}8) 3.48 (SD, 1.94) 3.63 (SD, 2.14) 3.22 (SD, 1.55)Ventilation (1}11) 7.24 (SD, 2.80) 6.74 (SD, 2.82) 7.79 (SD, 2.69)Household water supply 16 13 3Drainage 34 22 12Household rooms 1 2 2 02 2514113 3019114# 16 11 5Exposure covariates Glazed pottery cooking 53 31 22Eat locally grown food 73 46 27Perceived health risk 38 25 13Perceived environmental risks 56 40* 16Use pesticides 33 19 14Frequent alcohol consump-tion 11 7 14Note. SD, standard deviation.*P(0.05 by t test.than those in Community A. However, the secondcommunity had lower external emission sources,a higher internal emission index, and, because ofa warmer local temperature, a higher ventilationindex. Table 2 shows that average blood hemoglobinwas under clinically normal levels, 13.18 witha range of 9.84 to 16.5, and with signi7cantly lowerlevels in women than inmen; lead levels (B-Pb) were11.00, ranging from the lowest detected of 2.5 to31 lg per deciliter. B-Mn ranged from7.5 to 88 lg /L,with a median concentration of 15, the upper quar-tile starting at 20 lg /L; the upper 10% was above25 lg/L. In Community A, B-Mn,MAO, and Hb werehigher and B-Pb and plasma lipid peroxidation were

lower than those in Community B. Table 3 displaysthe results of the environmental monitoring. Rivermanganese at Community B showed a trend up todownstream. In Community A compared to B, man-ganese levels in food, soil, and well water werelower; total suspended particles, outdoor air, andindoor dust manganese were 2.7, 1.1, 3, and 3.14times higher. The distribution of B-Mn by sector isshown in Fig. 1, depicting a lower and less variableconcentration in the farther sectors. B-Mn geometricmeans in Community A (sectors 1 to 4) showed a bor-der signi7cant trend (slope, !0.09, P"0.10) withdistance from the source (sector 1, the closest to thepoint source of emission, a mean of 16.8, sector94 SANTOS-BURGOA ET AL.TABLE 2Descriptive Statistics of Biomarkers by CommunityUnits n Mean (SD) Minimum MaximumTotalBlood Mn lg/L 73 17.71 (11.99) 7.50 88.00Blood Pb lg/dl 73 11.00 (5.86) 2.5 31.00Plasma lipid peroxidation F.U.a 73 8.73 (11.52) n.d. 88.00MAO nmolb 73 64.96 (29.82) 13.92 182.05Hemoglobin mg/100mL 72 13.18 (1.40) 9.84 16.5Community ABlood Mn lg/l 46 18.26 (13.92) 10.00 88.00Blood Pb lg/dl 46 9.54 (5.06) 2.5 21.00Plasma lipid peroxidation F.U.a 46 4.64 (4.90) n.d. 26.49MAO nmolb 46 73.45 (30.93) 31.06 182.05Hemoglobin mg/100ml 45 13.67 (1.23) 10.91 16.50Community BBlood Mn lg/L 27 16.76 (7.81) 7.50 45.00Blood Pb lg/dl 27 13.48 (6.38) 3.00 31.00Plasma lipid peroxidation F.U.a 27 15.70 (15.67) 2.29 88.00MAO nmol b 27 50.51 (21.50) 13.92 88.00Hemoglobin mg/100ml 27 12.36 (1.29) 9.84 15.47Note. SD, standard deviation; n.d., not detectable (given a value of 0.00).a F.U., Fluorescence units.bMAO refers to platelet monoamine oxidase activity and is expressed in nanomols of 4-HOQ formed per hour per protein milligram.2 with 15.6, sector 3 with 14.2, and sector 4, thefarthest, with 16.5). Six cases of tremor and/ornumbness were identi7ed in Community B. All ofthemwere in the age range of 46 to 56 years (average50.2), two of them being males. Their B-Mn levelswere in the range of 10 to 45 lg/L; comparedwith theremaining of 67 subjects their B-Pb and plasma lipid

peroxidation levels were higher (means, 16.1 versus10.6, and 13.3 versus 8.3, respectively), and theMAO, schooling, and Mini-Mental performancescores were lower (means, 41.6 versus 68.3, 0.7 ver-sus 2.3, and 18.0 versus 21.0).Age was signi7cantly and inversely related to B-Mn level (partial correlation coef7cient of !0.26,P"0.04), being signi7cant for women and not formen (Fig. 2). On bivariate scatter plots we observeda direct relationship between manganese and lead,as well as with the socioeconomic index, and aninverse relationship between plasma lipid peroxida-tion with manganese and hemoglobin and betweenmanganese and hemoglobin, the 7rst four being stat-istically signi7cant and not the last one. The Hbreduction started at 10 lg/L of B-Mn. MAO was in-versely associated with lead and peroxide, with bor-derline signi7cance. Table 4 shows the mainpredictive least square regression models of thesebiomarkers, con7rming the bivariate observationsand showing the inversemanganese}hemoglobin as-sociation. A statistically signi7cant multinomial lo-gistic regression analysis (adjusted by communityand smoking) of the blood manganese}blood perox-ide concentrations demonstrates an inverse U curveof the regression coef7cients. This curve is presentedin Fig. 1, where the distribution of B-Mn was dividedinto six centiles, and the regression coef7cients wereobserved compared to the third centile. Here, a co-ef7cient of!0.65 referred to a reduction of the lipidperoxidation for those at the fourth centile.Adjusted risk ratios for the different neuro-psychological tests are included in Table 5. The mod-els with the highest explanation of the effects arethose related to motor strength, coordination, andcognitive performance. Themotor test employed was7ngertip touching. The most relevant of these arethe results of the Mini-Mental Examination. Weused a cutpoint of 17, to culturally and socially adaptit to the rural Mexican population. This model wasadjusted by hemoglobin, alcohol, age, sex, andschooling since the later one is signi7cantly relatedto test performance. The logistic regression oddsratio adjusted for schooling yielded a 4.9 (1.4 to 17.4)estimate (shown in Table 6). The unadjusted andadjusted models for the Mini-Mental test are also

shown in Fig. 2, the 7rst graph describing a lack oftrend for the Mini-Mental test with increasing man-ganese concentrations, while the second graphEXPOSURE TO MANGANESE 95TABLE 3Descriptive Statistics of Environmental Data by CommunityUnits n Mean (SD) Minimum MaximumTotalRiver Mn mg/L 7 days, 5 sites 45.34 (0.002) 0.00 240.25Total food Mn mg/100 dry g 16 2.02 (1.19) 0.65 5.25Soil Mn mg/kg 10 sites 119.25 (85.78) 11.84 264.00Total suspended particles lg/m3 5 days 27.03* (21.59) 6.44 67.03Outdoor air Mn in PM10lg/m3 5 days 0.07* (0.02) 0.03 0.10Well water Mn mg/L 14 39.95 (75.59) n.d. 241.90Indoor air PM10lg/m3 10 homes 28.56* (4.95) 17.87 35.19Indoor dust Mn mg/cm2 10 homes 0.62* (0.55) 0.07 1.98Community ARiver Mn mg/L no river n.a. n.a. n.a.Total food Mn mg/100 dry g 7 samples 1.87 (1.19) 0.72 2.65Soil Mn mg/kg 5 sites 95.75 (74.91) 11.84 194.15Total suspended particles lg/m3 5 days 43.68a (12.08) 26.81 56.69Outdoor air Mn in PM10lg/m3 5 days 0.10a (0.02) 0.09 0.10Well water Mn mg/L 7 33.59 (66.87) n.d. 183.56Indoor air PM10lg/m3 10 homes 28.56a (4.95) 17.87 35.19Indoor dust Mn mg/cm2 5 homes 1.10a (0.52) 0.73 1.98Community BRiver Mn mg/L 7 days, 5 sites 45.34 (87.85) 0.00 240.25Total food Mn mg/100 dry g 9 samples 2.13 (1.48) 0.65 5.25Soil Mn mg/kg 5 sites 142.74 (100.42) 19.77 264.00Total suspended particles lg/m3 5 days 16.72a (25.19) 6.44 67.03Outdoor air Mn in PM10lg/m3 5 days 0.03a (0.003) 0.03 0.03Well water Mn mg/L 7 46.30 (88.40) n.d. 241.90Indoor air PM10lg/m3 n.a. n.a. n.a. n.a.Indoor dust Mn mg/cm2 5 homes 0.35a (0.30) 0.07 0.83Note. SD, Standard deviation; n.a., not available; n.d., not detectable.aExpressed as geometric mean.bMedian of two 7lters.*P(0.05 by t test.FIG. 1. Blood manganese by sampling sector (5, community B).shows the estimated risk ratios for each tertile ofB-Mn for reducedMini-Mental score, and other tests

displaying a U-shaped dose}response curve. Only theadjusted model describes the relation adequately.Seventeen of 73 subjects had classic chronic bron-chitis (cough with phlegm during more than3 months throughout 3 years), and another 2 hadonly a chronic cough. Twenty-eight of 32 subjectshad positive dense nodulations and 20 had evident7brosis. Multivariate logistic regression modelsshowed no signi7cant risk ratios related to commun-ity, B-Mn, or proximity to point source. Perception ofhealth and environmental alterations was unrelatedtomanganese levels and toMini-Mental Examinationperformance.AsshowninTable7,theperceptionofenvironmental alterations was directly related toschooling, the unawareness of the relevance ofa source of pollution in Community B, and the fre-quent use of risk-bearing pesticides. Adjusted for theidenti7ed associated variables to blood manganese,hluregressionanalysisidenti7ed the contribution ofmanganese in food, air, and home dust (Table 8);amodel speci7c to Community B identi7ed riverman-ganese as another statistically signi7cant factor.96 SANTOS-BURGOA ET AL.FIG. 2. Biomarkers by age, gender, and socioeconomic index.DISCUSSIONBased on the results of this study, we identi7edplasma lipid peroxidation activity reduction, lowerMini-Mental performance, and poor motor functiontests at above 15 lg/L of B-Mn. Obvious clinicaltremor and numbness were identi7ed at above25 lg/L, and an inverse linear effect on hemoglobinwas identi7ed starting at 10 lg/L.Biases in this study can occur due to its design,population selection, and instrument measurementamong other factors. Although this is a cross-sec-tional study, inferences based on these 7ndings arestronger given the chronicity of exposure and effects(31). However, the high prevalence might bias therisk estimators away from the null (32), and wesuggest that the risk ratios be consideredmore as anindex of effect rather than for obtaining its realmagnitude. We have no information on high migra-tion rate, but we can say that length of residency inthe community and age are highly correlated, evenwhen periods of time when subjects had lived outsidethe community are taken into account. This is rel-

evant if we wish to consider especially susceptiblesubjects who may have left the mining district area;loss of susceptible subjects may bias results towardnull. A de7nitive limitation of this design is that weare unable to identify changes over time, leavingopen the question of the potential reversibility ofeffects resulting from lifetime exposures (33, 34),although acute clinical intoxication has been shownas reversible (35). A similar limitation is observed asfor the analysis of potential progression of healtheffects (36). This limitation is enhanced, as we didnot include subjects less than 14 years of age; thiswas a design limit requested locally. Therefore, ourinferences relate only to teenagers and adults. Thedesign does not allow us to examine subjects at veryearly ages or at the in utero stage, when the develop-ing nervous system is most susceptible and whenpreferential absorption of manganese occurs.For practical reasons and given the time limit forresponding to governmental and community re-quirements, subjects were recruited at their homesonce this was probabilistically selected. The poten-tial bias of the worst case being self-selected is notsupported by our risk perception survey. The popu-lation sample is certainly biased as regards age andsex structure toward those who are available duringthe working week, strengthening our inference thatwe are gathering information on those environ-mentally exposed at the community level.The exposure biomarker B-Mn is a good body bur-den indicator (23, 37}41); this is the case whenEXPOSURE TO MANGANESE 97TABLE 4Least Squares Predictive Models of BiomarkersDependent variable Independent variable Coef7cient 90% Con7dence interval Adjusted R2aBlood manganese (log) Lead (log) 0.29 0.15}0.43 0.21Hemoglobin !0.08 (!0.14}(!0.03)Age !0.004 (!0.009)}(!0.0002)Sector distanceb !0.06 (!0.11)}(!0.009)Constant 3.52 2.7}4.4Lead (log) Manganese (log) 0.48 0.25}0.71 0.21Hemoglobin 0.07 (!0.00)!0.15Communityc 0.43 0.21}0.64Constant !0.60 (!2.01)}(0.80)Plasma lipid peroxidation (log) Manganese (log) !0.61 (!1.06)}(!0.17) 0.32

Community 1.31 0.90}1.72Constant 1.57 0.23}2.92Plasma lipid peroxidation (log) Manganese (log) !1.20 (!1.74)}(!0.67) 0.61Community 1.70 1.17}2.24Smoker !1.40 (!0.67)}0.40Constant 2.77 0.87}4.67Monoamine oxidase (log) Alcohol 0.39 0.17}0.60 0.24Community !0.38 (!0.54)}(0.22)Constant 3.88 3.41}4.34Hemoglobin Manganese (log) !0.96 (!1.61)}(!0.31) 0.25Age !0.02 (!0.03)}(!0.003)Sex !1.12 (!1.71)}(!0.54)Sector distance !0.31 (!0.47)}(!0.14)Constant 19.49 17.07}21.93Note. All R2have P(0.05.aAdjusted R2is interpreted as the proportion of variance explained by the model.b Sector dstance refers to the sampling sector, as for distance from the point source, 1 being the closest and 5 the farthest.c In all analyses Community A was coded as 1 and B as 2.FIG. 3. Trend in log blood peroxide and log blood manganese.considering chronic exposures rather than acutehigh ones, as peak doses may be rapidly excreted(42). This was our best estimator of exposure andwell described by the exposure pathways. It is ar-gued that the inhalation route is more ef7cient thanthe digestive route (4), the former considered bysome to be 100% and the latter around 3}5%. Con-sistently, the air concentration was the main con-tributor to blood manganese in the exposure modelin Table 8, having then home dust manganese andfood manganese, both using the oral pathway, asadditional contributing factors. A homeostaticmech-anism has been shown for the oral route, where thebody is protected against manganese toxiticy by lowabsorption and/or rapid presystemic elimination bythe liver (43). This study supports the observationthat manganese competes with iron metabolism, ashemoglobin was inversely related to it. There isa wide gradient of exposure, but none of the highestexposures were occupationally related since none ofthe selected subjects were miners; this is under-standable since most of the mine workers come fromoutside the communities. Upper limits were wellinto the toxic levels identi7ed in a report of an occu-

pationally exposed population in Mexico where twointoxicated miners had blood manganese of 76 and98 SANTOS-BURGOA ET AL.TABLE 5Regression Models for Manganese Exposure Effect with the Different Neuropsychologic TestsTest Coef7cientaCon7denceintervalModelcadjusted R2Risk ratiobCon7denceintervalAttention and concentrationTrail Making 1.00 0.40}1.59 0.20 1.68Direct digit retention 0.78 0.23}1.33 0.09 2.15Inverse digit retention 0.65 0.05}1.24 0.03 1.89Motor behaviorMotor strength (continuous) 0.53 0.15}0.91 0.44 1.59Motor strength (categorical) 0.19 6.7 1.5}29.8Finger tip touching 0.65 0.02}1.28 0.21 1.89Asymmetric rhythm 0.93 0.10}1.76 0.14 2.49Election reaction 0.58 0.20}0.97 0.26 5.40Symbolic actions 0.52 0.22}0.82 0.12 1.67CognitivedMini-Mental:concentration 2.00 0.56}3.42 0.34 7.11Memory !0.45 (!0.85)}(!0.05) 0.20 0.64Follow instructions !0.13 (!0.25)}(!0.00) 0.03 0.88Writing 0.43 0.07}0.80 0.04 1.52Total (continuous) 2.05 0.01}4.10 0.03Total (categorical scoreless than 17) 0.27 11.70 1.5}94.5ClinicalHand numbness (categorical) 0.18 15.5 1.3}181.4aCoef7cients were estimated by least squares adjusted for other variables (most frequently age, schooling, community, alcohol, andoccasionally age and sex). Only models with statistically signi7cant coef7cients associated with blood manganese are included; theircon7dence intervals exclude the null value. All models are with 90% C.I.bRisk ratios, as estimated from the regression coef7cients, are interpreted as how much risk increases when blood manganese is abovethe 75th percentile, in comparison to the lowest population 25th percentile level. Only statistically signi7cant ratios are included.c Interpreted as the proportion of variance explained by the model; in logisitc estimation we used the pseudo R2

. All R2have a P(0.05.d The Mini-Mental test is heavily in8uenced by education. The models for concentration, writing, and total Mini-Mental and categoricaltests are adjusted by other variables and by education.FIG. 4. Neuropsychologic test results for manganese. (A) Blood manganese and mini-metal score. Nonadjusted model. (B) Risk bytertile of blood manganese.120 lg/L (44). The observed concentrations were in-versely related to age. This suggests that we furtherseek to test the hypothesis of a preferential absorp-tion of manganese at an early age (45}47).Blood manganese concentrations were signi7-cantly related to the point source in the community,and the exposuremodel showed an important contri-bution of air sources; as with other metal exposuresEXPOSURE TO MANGANESE 99TABLE 6Mini-Mentala Score Performance DeAcit Risk RatiosVariables in modelsbPointestimate90% Con7denceintervalModel 1c Blood manganese 2.82 0.94 to 8.52Model 2 Schooling 11.15 1.88 to 66.22Model 3 Blood manganese 4.92 1.39 to 17.38Schooling 16.37 2.53 to 105.65aMini-Mental: Total Score (categorical score less than 17).b The 7rst two logistic models are unadjusted; the last one isadjusted only for the variables shown.cModels are estimated for risk of de7cit when subject’s bloodmanganese is above the median or when the subject has noschooling.TABLE 7Environmental Risk Perception Predictive VariablesaVariablePointestimate90% Con7denceintervalBlood manganese (above mean) 0.26 0.07 to 0.92Low schooling 0.06 0.01 to 0.28Familiar with use of pesticides 2.5 0.73 to 8.56Residence in Community A 5.57 1.60 to 19.37aRatios estimated from logistic linear regression.TABLE 8

Environmental Manganese Exposure Factors ThatContribute to Integrating Human Population Exposurea90% Con7denceVariable Coef7cient intervalManganese in food 0.13 0.00}0.26Outdoor air Mn in PM10 (log) 0.47 0.18}0.76Manganese in home dust(log) 0.05 0.00}0.09aManganese tertiles as a dependent variable, adjusted for lead,hemoglobin, and socioeconomic index, and autocorrelation usingHildreth}Lu regression. Soil and wellmanganese were noncontri-buting. River manganese was only pertinent to Community B.(48) home dust was an important determinant, pos-sibly being introduced through air or through step-ping into dry deposited manganese-polluted soil.Certainly both communities are different in theirmanganese contributions; both have manganese inthe soil, although this is highest in Community B,and the air concentrations are much higher in A,further supporting the relevance of the air pathway.Historical outdoor air particles and manganesemeasurements were possibly underestimated by thesurvey measurements; there are company reports tothe state environmental authority (49) of 1996}1997data including median TSP and manganese concen-trations of 35.19 and of 1.92 lg/m3, respectively. Fur-thermore, a survey done a couple of weeks before ourstudy by another group (50) showed Mn air concen-trations with a geometric mean of 0.07 lg/m3in thePM2.5 fraction and of 1.8 lg/m3in the PM15 fraction(PM10 fraction not reported). Therefore, our resultsshould be taken as qualitatively more than quantit-atively appropriate for cumulative exposure estima-tion. Longitudinal monitoring would providea better assessment of manganese concentration inthe river water as an important source ofmanganesein the downstream community. We believe that theexposure pathway is indirect since the local popula-tion does not drink this water. However, from theriver they obtain freshwater shrimp, which feedfrom the river plankton deposited in the sedimentwhere they reside, easily concentrating manganese,as phytoplankton andwater invertebrates have been

attributed bioconcentration factors of 2500}6300and 10,000}40,000, respectively (2, p. 132). We werenot able to analyze this food pathway.Manganese inwell water was inversely related to B-Mn, possiblybecause the population does not use the closestwater source;as this was the criterion to assignexposure;but the one with the lowest concentrationand farthest from the point source. We had a verylimited food consumption questionnaire and thismight have accounted for the poor performance ofthe food pathway, rather than considering that thisis unrelated. Our questionnaire was more gearedtoward lead-bearing food consumption than manga-nesebearing food consumption. Our food samplingincluded a single nonstandardized conveniencesample at a high proportion of homes, and thisshould be improved in future research.Blood manganese concentrations in CommunityA were 11% higher than those in Community B; wefurther took a convenience sample in far away com-munities and in clinic patients in Mexico City show-ing 27 and 74% higher concentrations. Forcomparison within Mexico, a probabilistic sample ofMexico City’s pregnant women (to be published) hadan average B-Mn of 7.72 (range 5.6 to 11.4), depict-ing generally higher blood manganese in Mexico;this might be because dietary factors make Mn in-gestion in the upper range of the United Statesrecommended intake (national daily average of7.9 mg, with some states above 10). Geometric meanB-Mn in Community A was higher than the reportedSouthWestern Quebec concentration (51, 52), whereMMT is currently being used as a gasoline octane100 SANTOS-BURGOA ET AL.booster; the highest concentrations were in therange of miners reported as occupationally in-toxicated (44). Outdoor air manganese was twice theone reported in Soth Western Quebec and the refer-ence United States concentrations (53), similar tothe Canadian ones (54) and to the ones reported forMexico City (55). Mn in soil was 3.6 times the aver-age Canadian and 5.7 times the United States (45)concentrations. Well water manganese was 2.5times higher than the South Western Quebec tapwater. This clearly de7nes this population as a chro-nically intermediate level-exposed group. Still otherexposure assessment limitations preclude a com-

plete exposure assessment, such as the lack of analy-sis of time activity patterns in the study population,the external validation of the air sampling, and theneed to differentiate recent exposure by using man-ganese in serum.Of the expected health effects, both the respirat-ory symptoms and the radiological data fail to sup-port an association with Mn exposure. It is possiblethat the intensity (time and concentration) is not ashigh as that in other settings. However, other clini-cal and biomarker effects were evident. Lipid peroxi-dation happened to be useful in identifying earlyeffects and not so monoamine oxidase activity. Theinverse U-shaped curve is consistent with the biolo-gical conceptual model for essential metals (56) con-sistent with the possible atioxidant activity ofmanganese (9). Plasma lipid peroxidation activitywas greatly reduced in Community A versus B inspite of the not so high B-Mn difference (ratios being3.4 and 1.09, respectively), possibly pointing towardthe most effective effect of the inhaled route. Theabsence of association with MAO may be a usefuldifferential diagnosis tool, but requires further ex-amination as regards the time of onset of symptomsand validation. Several subjects had evident tremorand numbness, not requiring any further clinicalmeasurements; some of these could not be assessedfor neuropsychological tests because of their handi-cap. All the data on these subjects are consistentwith the overall results but their relationship to theenzymes, possibly showing a different stage of theeffects. All the testing was done with standardizedprocedures and well-trained personnel; still theirsensibility could be improved by other computer-based tests (57). Although motor strength and coord-ination effects were clearly identi7ed in the surveypopulation, the mental de7ciency identi7ed by theMini-Mental Examination showed the most worri-some result of this study. Mn and age are signi7-cantly and inversely related (!0.25), as is the caseof education and age (!0.63), the latter witha stronger association as the older people had lesschance for schooling. That is why the Mini-Mentalmodel was adjusted for age and schooling. TheMn}Mini-Mental association held while consideringsocioeconomic and schooling covariates; their tem-

porality is dif7cult to determine. The test has beenrelaxed in its cutpoint criteria from the score of 23used internationally (19) to the rural Mexican cut-point of 17, as adapted from locally developed stud-ies. Further adaptations have included the queryabout locally familiar elements. The public healthimpact of this 7nding is of fundamental importance.Risk was 12 times higher in the upper concentra-tions versus that at the lower exposure concentra-tions. Still other, more sensitive effects (olfactory,sensitivity, balance, re8exes, and other neurologicalsigns) were not explored, giving a partial 7gure ofthe potential neurological effects.The B-Mn and hemoglobin inverse associationfound was interesting (58), although several issueshave yet to be looked into. As with the Mini-MentalExamination, this association is socioeconomicallyand nutritionally related. The effect of Mn was high-er than the known one of lead (59). The study did notassess nutritional status, and we cannot correctlyassess iron intake, nor do we have information onserum iron since this element was not measured inthe study. However, these 7ndings are consistentwith those in the literature (45, 59}61) and should bemeasured in future projects; the nutritional evalu-ation needs to be enhanced in order to address totalexposure (62).It was necessary to explore the lead interactionsince this toxicant is highly prevalent in Mexicandish and cooking ware, and it has neurotoxic poten-tial. The blood lead manganese concentrations areconsistent with those of other Mexican rural com-munity studies, where the main source of lead is lowtemperature-glazed pottery used for cooking andstoring food (63). Other authors have identi7ed aninteraction of lead and manganese: In ther late1970s Zielhius in Holland (64) identi7ed this inter-action, and later on Truckenbrodt found it whenexamining different occupations (65); furthermore,Saavedra (66), in a study of battery workers inMexico, determined the same relationship. B-Pb andB-Mn were certainly correlated as they do not com-pete for metabolic pathways; however, in our studylead was seldom identi7ed as related to neurotoxiceffects: it was shown to be associatedwith the neuro-psychological verbal word 8uidity test, with some

motor function tests (symbolic actions, con8ictivereactions), and in the writing component of theMini-Mental test in multivariate adjusted models.EXPOSURE TO MANGANESE 101This may be because manganese and lead have dif-ferent brain sites of action.The study limitations open up questions and im-provements for future research. The 7ndings of thisstudy are biologically plausible and consistent withthose in the literature. This study provides a cross-sectional picture of a population with lifetime expo-sure that warrants a longitudinal examination. Thisis in our immediate research plans; 10 to 30% of thepopulation in the examined group suffer from differ-ent degrees of effects, and we expect these effects tobe reduced or prevented in the younger population ifexposure is limited in an important way. Although itis still premature to set a public health goal, includ-ing safety factors may lead to a goal of safe B-Mnconcentration, in the range of 0.8}1.2 lg/L.Mean airmanganese concentrations are at the currently dis-cussed reference concentrations of EPA (53) and Ca-nadian ones (54). A sanitary goal now can only betemporary since this has to be supported by im-proved exposure pathway assessment and more sen-sitive clinical tests. None of the mentionedlimitations preclude the public health interventionsthat have been proposed locally and to federalauthorities. This supports a precautionary approachto environmentally exposing the general populationto manganese in any of its forms and media untila population-based description of the dose}responsecurve is obtained within a wider range of exposureand effects.While all the limitations of this study areaddressed through future research, federal and statehealth and environmental authorities have deter-mined to reduce air emissions to half their currentlevels, and have established several environmentalhygiene actions in the community with greatest ex-posure. We strongly feel that an important risk ispresent which deserves further research and inter-vention for the bene7t of local communities as wellas for addressing fundamental scienti7c questions.ACKNOWLEDGMENTSWe thank the support of Irma Gutierrez, State Secretary ofHealth, David Sanchez-Monroy, the 7eld personnel from theState Health Services and the Mexican Institute of Social Secur-

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