The Importance of Veterinary Toxicology for Animal Agriculture and the Food Supply Birgit Puschner DVM, PhD, Dipl. ABVT California Animal Health and Food.

The Importance of The Importance of Veterinary Veterinary

Toxicology for Toxicology for Animal Agriculture Animal Agriculture

and the Food and the Food SupplySupplyBirgit PuschnerBirgit Puschner

DVM, PhD, Dipl. ABVTDVM, PhD, Dipl. ABVTCalifornia Animal Health California Animal Health

and Food Safety and Food Safety Laboratory SystemLaboratory System

School of Veterinary School of Veterinary MedicineMedicine

University of California, University of California, DavsDavs

Belgium PCB and Dioxin Belgium PCB and Dioxin IncidentIncident

In January, 1999, In January, 1999, 500 tons of animal 500 tons of animal feed were feed were contaminated with:contaminated with: ~ 50 kg of PCBs and~ 50 kg of PCBs and 1 gram1 gram of dioxinof dioxin

Distributed to Distributed to animal farms in animal farms in BelgiumBelgium

1 storage tank of

fat

10 livestock feed manufacturers

2140 pork, poultry and beef

farms

Timeline of eventsTimeline of events Feed contamination: January, 1999Feed contamination: January, 1999 Early Feb, 1999: Early Feb, 1999: VeterinarianVeterinarian diagnosed diagnosed

chicken edema disease chicken edema disease prompted prompted investigationinvestigation

Mid March, 1999: Mid March, 1999: Feed and animal tissues were sent for tox Feed and animal tissues were sent for tox

testingtesting Veterinarian considered fat in animal feed the Veterinarian considered fat in animal feed the

most likely sourcemost likely source April 26, 1999: Dioxin and PCB April 26, 1999: Dioxin and PCB

contamination confirmed by laboratorycontamination confirmed by laboratory

60 billion Belgian francs or ~ 1.5

billion U.S. dollars

Animal agriculture is an easy targetAnimal agriculture is an easy target Toxicants can be widely distributedToxicants can be widely distributed Veterinarians may be the first Veterinarians may be the first

respondersresponders Veterinary toxicology laboratories Veterinary toxicology laboratories

are crucial in investigationsare crucial in investigations

Toxicology Case StudiesToxicology Case Studies

Lesson learned…Lesson learned…

Poisoning Case in Dairy Poisoning Case in Dairy CowsCows

22 – 24 lactating cattle died over 22 – 24 lactating cattle died over a period of 9 days in a herd of ~ a period of 9 days in a herd of ~ 300 cows300 cows

Affected cattle in one penAffected cattle in one pen Clinical signs:Clinical signs:

Reduced or no rumen motility Reduced or no rumen motility Lethargic and hunched upLethargic and hunched up Decreased milk productionDecreased milk production Increased respiratory rate and effortIncreased respiratory rate and effort

↓ ↓ Tongue Tongue tonetone

↓ ↓ Palpebral Palpebral reflexreflex

TimelineTimeline

Consultation with herd vet: Day 1Consultation with herd vet: Day 1 Necropsies: Day 2Necropsies: Day 2 Hold placed on milk and milk Hold placed on milk and milk

products: Day 2products: Day 2 Awaiting toxicology resultsAwaiting toxicology results Awaiting possible danger to the food Awaiting possible danger to the food

supplysupply Toxicology testing: Day 3-5Toxicology testing: Day 3-5

Toxicological AnalysesToxicological Analyses OleanderOleander OP and carbamate OP and carbamate

insecticidesinsecticides Ionophore antibiotics Ionophore antibiotics

(monensin, etc.)(monensin, etc.) Toxic plants: tree Toxic plants: tree

tobacco, jimsonweed, tobacco, jimsonweed, poison hemlock, yews, poison hemlock, yews, larkspurs, lupine, larkspurs, lupine, foxglove, foxglove, rhododendronsrhododendrons

HypocalcemiaHypocalcemia HypomagnesemiaHypomagnesemia

LeadLead Arsenic, Mercury, Arsenic, Mercury,

CadmiumCadmium CopperCopper SeleniumSelenium GC/MS screen: GC/MS screen:

pesticides, drugs, natural pesticides, drugs, natural productsproducts

FERN LC/MS screen: a FERN LC/MS screen: a large variety of chemicals large variety of chemicals that may result in high that may result in high morbidity or mortalitymorbidity or mortality

Rat poisonsRat poisons

Decision with regards to safety of milk & Decision with regards to safety of milk & dairy productsdairy products

Final Diagnosis – Day 7Final Diagnosis – Day 7 Diagnosis of Botulism Type C – SourceDiagnosis of Botulism Type C – Source Challenges:Challenges:

Vagueness of clinical signsVagueness of clinical signs Tests for botulinum toxin not sensitive Tests for botulinum toxin not sensitive

enoughenough Tox testing crucial!Tox testing crucial! Source of toxinSource of toxin

March 2006March 2006

47th and Stockton blvd

Cooked mushroom samples positive for alpha- and beta- amanitin.

Onions

Mushroom pieces

Toxicology InvolvementToxicology Involvement

beta-Amanitin

alpha-Amanitin

Soup available for testing – rapid Soup available for testing – rapid diagnosisdiagnosis

New methodology (LC/MS)New methodology (LC/MS)

Poisoning Case in Dairy Poisoning Case in Dairy CowsCows

6 lactating cattle (total in pen = 6 lactating cattle (total in pen = 16) died within 24 hours in a herd 16) died within 24 hours in a herd of ~ 600 cowsof ~ 600 cows

““Just found dead”Just found dead” Other information:Other information:

All animals are off feed a littleAll animals are off feed a little All animals on dairy get the same ration: All animals on dairy get the same ration:

TMR (corn silage and premix, top-dressed TMR (corn silage and premix, top-dressed with hay)with hay)

Owner washed a spray tank the day beforeOwner washed a spray tank the day before

Diagnostic Work-upDiagnostic Work-up

Necropsies: cardiotoxic eventNecropsies: cardiotoxic event Toxicology testing: oleandrinToxicology testing: oleandrin

GI contents, liver, muscle & feedGI contents, liver, muscle & feed Serum, urine, milkSerum, urine, milk

+EPI (577.40) CE (20) CES (5): 7.375 min from Sample 1 (D0404700-My282 Liver, 200mg) of 081004-28.wiff (Turbo Spray) Max. 2.1e6 cps.

100 150 200 250 300 350 400m/z, amu

0.0

5.0e5

1.0e6

1.5e6

2.0e6

Inte

ns

ity, c

ps

373.3337.3

355.3

319.3433.3291.2

Results Results within a within a

few hours few hours (LC/MS)(LC/MS)

Benefit of Toxicology Benefit of Toxicology TestingTesting

Rapid diagnosisRapid diagnosis Testing of milk and meatTesting of milk and meat

Perchlorate

PerchloratePerchlorate

Developed LC-MS/MS method in Developed LC-MS/MS method in 2 weeks2 weeks

Method detection limit: ~ 0.8 Method detection limit: ~ 0.8 ppbppb

46 milk samples:46 milk samples: All samples were positiveAll samples were positive 1.54 ppb to 20 ppb1.54 ppb to 20 ppb

Perchlorate Interlab Perchlorate Interlab Comparison StudyComparison Study

Sample Sample No.No.

FDA/CFSAN – FDA/CFSAN – IC-MS/MSIC-MS/MS

CAHFS – HPLC-CAHFS – HPLC-MS/MSMS/MS

Milk Milk #1#1

5.21ppb5.21ppb 5.83 ppb5.83 ppb

Milk Milk #2#2

4.59 ppb4.59 ppb 5.28 ppb5.28 ppb

Milk Milk #5#5

4.66 ppb4.66 ppb 5.28 ppb5.28 ppb

Milk Milk #7#7

4.70 ppb4.70 ppb 4.85 ppb4.85 ppb

Milk Milk #8#8

4.59 ppb4.59 ppb 5.82 ppb5.82 ppb

Perchlorate Regulatory Perchlorate Regulatory IssuesIssues

NAS recommendation: 0.7 NAS recommendation: 0.7 µµg/kg/dayg/kg/day Drinking water equivalent level Drinking water equivalent level

(DWEL)(DWEL) 24.5 ppb for an adult24.5 ppb for an adult 4 ppb for infants4 ppb for infants

CA - Public health goal: 6 ppbCA - Public health goal: 6 ppb

Perchlorate, Dairy Perchlorate, Dairy Cattle and Human Cattle and Human

HealthHealth Human health:Human health:

WHO – iodine deficiencyWHO – iodine deficiency Rapid transfer of dietary perchlorate Rapid transfer of dietary perchlorate

to milkto milk Perchlorate in dairy cows:Perchlorate in dairy cows:

Ruminants – biofilters?Ruminants – biofilters? Perchlorate intake and milk iodidePerchlorate intake and milk iodide

Goal: limit perchlorate content Goal: limit perchlorate content of the dairy cow’s dietof the dairy cow’s diet

Insecticide CasesInsecticide Cases Cattle: Cattle:

PhoratePhorate 167 deaths167 deaths Diagnosis Diagnosis

established established within hourswithin hours

Analysis of milk Analysis of milk and fat within and fat within hourshours

HumansHumans Thai food Thai food

restaurantrestaurant 107 affected 107 affected

peoplepeople Methomyl Methomyl

exposureexposure

MethomylMethomyl

Testing of food, and Testing of food, and food ingredients (oil, food ingredients (oil, salt, herbs)salt, herbs)

MycotoxinsMycotoxins

AflatoxinsAflatoxins FumonisinsFumonisins OchratoxinOchratoxin Tricothecene mycotoxinsTricothecene mycotoxins Penitrem APenitrem A ZearalenoneZearalenone

Algal ToxinsAlgal Toxins

SaxitoxinsSaxitoxins

AnatoxinsAnatoxins MicrocystinsMicrocystins

ImportanceImportance

Testing for toxicants in a Testing for toxicants in a large number of matriceslarge number of matrices

Diagnosis of intoxicationsDiagnosis of intoxications Prevention of Prevention of

intoxicationsintoxications Ensuring food safetyEnsuring food safety Assisting with risk Assisting with risk

assessmentsassessments Providing information to Providing information to

regulatory agenciesregulatory agencies

www.cahfs.ucdavis.edu

CAHFS Toxicology CAHFS Toxicology LaboratoryLaboratory

Member of FERNMember of FERN Received funding through the Received funding through the

Homeland Security DepartmentHomeland Security Department Largest Vet Tox Lab in the CountryLargest Vet Tox Lab in the Country

Highly trained personnelHighly trained personnel Continuous method development Continuous method development

and expansion of existing testingand expansion of existing testing