Results and Discussion Effect of tannery effluent on water and soil profile, plant growth and human health 51 RESULTS AND DISCUSSION In developing as well as underdeveloped countries, the industrial effluents are released directly or indirectly into natural water resources, mostly without proper treatment, thus posing a serious threat to the environment (Altug and Balkis, 2009). Environmental pollution is an extremely important issue today, affecting all of us in one way or the other. Due to rapid increase in human population and industrialization, the demand for natural raw materials and source of energy are increasing day by day (Abhay and Rajput, 2009). Many rivers of the world receive flux of sewage, domestic waste, industrial effluents and agricultural waste which contain substances varying from simple nutrients to highly toxic chemicals (Benazir et al., 2010). Tannery industry contributes significantly towards exports, employment generation and occupies an important role in Indian economy. Heavy metals released from tanneries are kept under environment pollutant category due to their toxic effects on plants, animals and human beings. They interfere with physiological activities of plants such as photosynthesis, gaseous exchange and nutrient absorption and cause reduction in plant growth, dry matter accumulation and yield (Sharma and Agrawal, 2005). They cause direct toxicity, both to human and other living beings due to their presence beyond specified limits. Heavy metal pollution of soil and waste water is a significant environmental problem and has a negative impact on human health and agriculture (Michalak, 2006). The reuse of waste waters and industrial effluents for irrigation to crop plants after proper dilution is an useful technique (Rehman et al., 2007). Tannery effluent can be diluted and reused for agriculture purpose which can also act as a good fertilizer (Mariappan and Rajan, 2002). In the selected area of our study the continuous discharge of tannery waste water has polluted the water and lands of the nearby villages namely Chinnalapatti, Begampur, Kottapatti and many other places. The potable water 4
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Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
51
RREESSUULLTTSS AANNDD DDIISSCCUUSSSSIIOONN
In developing as well as underdeveloped countries, the industrial
effluents are released directly or indirectly into natural water resources, mostly
without proper treatment, thus posing a serious threat to the environment
(Altug and Balkis, 2009). Environmental pollution is an extremely important
issue today, affecting all of us in one way or the other. Due to rapid increase in
human population and industrialization, the demand for natural raw materials
and source of energy are increasing day by day (Abhay and Rajput, 2009).
Many rivers of the world receive flux of sewage, domestic waste, industrial
effluents and agricultural waste which contain substances varying from simple
nutrients to highly toxic chemicals (Benazir et al., 2010). Tannery industry
contributes significantly towards exports, employment generation and occupies
an important role in Indian economy. Heavy metals released from tanneries are
kept under environment pollutant category due to their toxic effects on plants,
animals and human beings. They interfere with physiological activities of plants
such as photosynthesis, gaseous exchange and nutrient absorption and cause
reduction in plant growth, dry matter accumulation and yield (Sharma and
Agrawal, 2005). They cause direct toxicity, both to human and other living
beings due to their presence beyond specified limits. Heavy metal pollution of
soil and waste water is a significant environmental problem and has a negative
impact on human health and agriculture (Michalak, 2006).
The reuse of waste waters and industrial effluents for irrigation to
crop plants after proper dilution is an useful technique (Rehman et al., 2007).
Tannery effluent can be diluted and reused for agriculture purpose which can
also act as a good fertilizer (Mariappan and Rajan, 2002).
In the selected area of our study the continuous discharge of tannery
waste water has polluted the water and lands of the nearby villages namely
Chinnalapatti, Begampur, Kottapatti and many other places. The potable water
4
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
52
of the residential area was found to be salty and polluted and soil properties of
the cultivable land of the nearby area was also affected. The negligence of the
safe disposal of tannery wastes had led to deleterious effects on the biosphere
as a whole. Hence, in the present study, the impact of the tannery effluent on
water, soil, plant and human beings were assessed. The results of the study
entitled “Effect of tannery effluent on water and soil profile, plant growth
and human health” are presented and discussed as follows:
PHASE I
4.1 Characterization of the tannery effluent, target area water and soil samples
4.1.1 Characterization of tannery industry effluent
4.1.2 Biochemical profile of the target area water samples
4.1.3 Physicochemical characteristics of target area soil samples
PHASE II
4.2 Growth studies of selected plants using diluted tannery effluent
4.2.1 Biometric observations
4.2.2. Biochemical parameters
4.2.3 .Histochemical observations of root samples of the selected plants
4.2.4. Yield parameters
PHASE III
4.3 Health profile of the tannery industry workers
4.3.1 Hematological parameters
4.3.2 Assessment of the liver function
4.3.3 Assessment of the renal function
4.3.4 Assessment of metal contents
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
53
PHASE I
4.1 Characterization of tannery effluent, target area water and soil samples
4.1.1 Characterization of tannery industry effluent
Tannery industry contains several organic and inorganic chemicals,
which are toxic metals and they cause soil and ground water pollution. These
chemicals cause adverse effect on plant growth and the health of animals and
people living in that area. Processing of hides and skin to leather uses many
chemicals at various stages and hence releases many toxic substances at each
stage. The overall tanning process performed in drums can be characterized by
a high consumption of water and chemicals with collagen. Chemicals are added
in excess and are only partly taken up by the leather and the remaining is
released in the effluent (Scholz and Lucas, 2003).
Heavy metals can pose health hazards if their concentrations exceed
allowable limits. Even when the concentration of metals does not exceed these
limits there is still a potential for long-term contamination, and heavy metals are
known to accumulate within biological system (Altaf et al., 2008). Hence the
effluent released is expected to have a higher amount of chemicals and toxic
metals.
In every step of tanning process a considerable amount of waste water is
released. The waste water was found to contain salts, fat, protein and
preservatives for soaking, lime, ammonia and sulphides for fleshing, trimming
and bating, chromium salts and polyphenolic compounds for tanning and
dye and solvent chemicals with metals for wet finishing. Hence tanneries
that perform the complete tanning process produces a complete tanning
mixed waste water. In this view, in the present study, the combined tannery
effluent was collected and characterized for certain physicochemical
parameters. The results of the physical parameters of the raw effluent
are presented in Table 6.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
54
TABLE 6
PHYSICAL PARAMETERS ASSESSED IN RAW TANNERY EFFLUENT
PARAMETERS RAW
EFFLUENT BIS LIMITS
IS 2490-2009
Colour Brown -
Odour Offensive -
Turbidity Turbid -
pH 10.5 5.5 - 9.0
Total hardness (mg/l) 5400 100
Electrical conductivity (mg/l) 24,500 NM
Total suspended solids (mg/l) 650 100
Total dissolved solids (mg/l) 17,150 2100
Values are mean of triplicates
NM - Not mentioned
BIS - Tolerance limits for industrial effluent discharged into inland surface waters prescribed by the Bureau of Indian Standards (2009)
The effluent released from tannery industry was brown in colour and had
an offensive odour. The colour of the effluent might be due to the presence of
biodegradable and nonobiodegradable high molecular weight organic
compounds and high amount of chemicals used during the processing and the
odour may be due to the processing of skin and hides by soaking and liming.
The yellowish brown colour might be hindering the penetration of sunlight
causing depletion in the rate of oxidation process (Ravibabu et al., 2007) and
this colour might be due to physico chemical treatments (Zahid et al ., 2006).
Turbidity is an expression of the optical property that causes light to
be scattered and absorbed rather than transmitted with no change in direction
or flux level through the sample (APHA, 2005). The turbidity of the effluent
might be due to the discharge of high concentrations of carbonate,
bicarbonate, chloride, calcium, magnesium and sodium used in tanning industry
(Chakrapani, 2005).
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
55
pH was recorded as 10.5, which was above the tolerance limit of
5.5 - 9.0 prescribed by the Bureau of Indian Standards (2009). The higher pH of
the effluent indicates the basic nature of the effluent. The pH of waste water
could vary due to the presence of various tanning and colouring materials.
According to Fadali et al.(2005), the pH of the tannery effluent assessed by
them was found to be 10.0, which was above the permissible limits and they
suggested that this alkaline pH of the effluent could affect the biological property
of the receiving water body.
Total hardness of the tannery effluent in the present study was found to
be 5400 mg/l. Hardness is an indication of calcium and magnesium found in
higher concentration in effluent.
The higher electrical conductivity value of the effluent indicates that
the discharge of chemicals as cations and anions were higher in the waste
water. The higher conductivity alters the chelating properties of water
bodies and creates an imbalance of free metal availability for flora and
fauna (Akan et al., 2008). Venkatesh et al. (2009) recorded that the electrical
conductivity, pH, chloride, sulfides, biological oxygen demand and chemical
oxygen demand in tannery effluent were much higher than the tolerance limits
for industrial effluent discharged into land surface.
Levels of total suspended solids (TSS) found in the effluent (650mg/l)
were greater than that of the permissible limit (100 mg/l). Somnath (2003)
reported that larger solid particulate matter remains suspended as a result of
charges on the surface of small particles in the effluent.
The effluent showed a higher level of total dissolved solids (TDS)
(17,150 mg/l) . The value was much greater than the tolerance limits (2100 mg/l)
prescribed by Bureau of Indian Standards. Total dissolved solids are mainly
due to carbonates, bicarbonates, chlorides, sulphates, phosphates, nitrates,
nitrogen, calcium, sodium, potassium and iron (Kannan et al., 2009). In the
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
56
liming section of tanning process, protein, hair, skin and emulsified fats are
removed from the hides, which are released in the effluent and therefore
increase the total solids (Bhalli and Khan, 2006).
Table 7 indicates the chemical characteristics studied in tannery effluent.
TABLE 7
CHEMICAL CHARACTERISTICS OF RAW TANNERY EFFLUENT
PARAMETERS RAW
EFFLUENT BIS LIMITS
IS 2490-2009
Chemical Oxygen Demand 3180 250
Biological Oxygen Demand 1300 30
Carbonate 9850 600
Bicarbonate 10423 NM
Calcium 1440 200
Magnesium 432 30-100
Chloride 5100 1000
Sodium 2300 NM
Potassium mg/l 600 NM
Fluoride 1.0 2.0
Nitrate 440 100
Nitrite 32 10
Sulphate 1080 1000
Chromium 19.3 2.0
Nickel 5.5 3.0
Zinc 10.8 1.0
Cadmium 4.2 2.0
Values are mean of triplicates
NM - Not mentioned
BIS - Tolerance limits for industrial effluent discharged into inland surface waters prescribed by the Bureau of Indian Standards (2009)
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
57
Chemical oxygen demand (COD) is the test used to measure pollution
of domestic and industrial waste (Chavan and Wagh, 2005). It is the amount of
oxygen required for the oxidation of inorganic matter using a strong chemical
oxidant. COD is tested to determine the degree of pollution in the effluent
samples (Bhalli and Khan, 2006). COD values in the effluent were found to be
12 times higher than that of the tolerance limits.
Biological oxygen demand (BOD) is the parameter which is widely
used to determine the pollution load of waste water (Chavan and Wagh, 2005).
It is the amount of organic matter in the water and the amount of oxygen
required by the micro organisms to stabilize the biologically decomposable
organic matter in wastes under aerobic conditions (Bhalli and Khan, 2006).
BOD of tannery effluent was found to be 1300 mg / l which was higher than that
of the BIS limits (30 mg/l).
Akan et al. (2007) also reported higher levels of BOD, COD and TSS in
tannery effluent. Industrial effluents and municipal sewage carry organic and
inorganic substances which utilize dissolved oxygen resulting in oxygen
depletion (Ravindran and vasudevan, 2008). Nearly 70% of the emission loads
of biochemical oxygen demand (BOD), chemical oxygen demand (COD)
and total dissolved solids (TDS) emanate from the pretanning operations
(Calherios et al., 2008b).
High carbonate and bicarbonate contribute to the total alkalinity of the
sample (Balakrishnan and Karruppusamy, 2005). Carbonate and bicarbonate of
the effluent were found to be 9850 mg/l and 10423 mg/l respectively. Usage of
sodium bicarbonate during the process of pickling in tannery industry might
have caused the excessive amounts of these in the effluent.
The cations calcium and magnesium present in the effluent were found
to be at higher levels (1440 mg/l and 432 mg/l respectively) compared to BIS
limits. Calcium and magnesium contribute to the hardness of the water and it
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
58
imparts unpleasant odour, when present in higher levels (More et al., 2002). The
tannery effluent contains fairly large amount of calcium and magnesium
because lime is used for loosening the hair.
Chloride is an indicator of pollution when present in higher
concentrations (Singh et al., 2009). Sodium chloride used as a dehydrating and
antiseptic agent is the source of chloride (Mehdi, 2005). The level of chloride in
the effluent (5100 mg/l) was 5 fold higher than that prescribed by BIS (2009).
The presence of very high amounts of chloride and sulphate is responsible
for high hardness and further it increases the degree of eutrophication
(Kannan et al., 2005).
The level of sodium and potassium in the effluent were 2300 mg/l and
600 mg/l respectively. Sodium sulphide is used in the liming process of hide and
skin. The residual sulphide in the range of 100 – 200 mg/l goes in the discharge
and causes serious environmental problem (Ram and Roger, 2004). The high
concentrations of sodium and chloride in the effluent were mainly due to the use
of huge salts in different stages of tanning process (Zahid et al., 2006).
Fluoride levels in the effluent were lesser (1.0 mg/l) than that of Bureau
of Indian Standards (2.0 mg/l). Very high nitrate content (440 mg/l) was present
in tannery effluent than the standard value. Nitrite content in tannery effluent
(32 mg/l) was also above the permissible limits (10 mg/l). Waste generated from
tanning generally contains much higher concentration of total dissolved solids
(TDS), total suspended solids (TSS), phenols, chromium, chlorides, nitrates,
nitrites, ammonia and heavy metals. Nitrate is the highest oxidized form of
nitrogen and causes blue baby disease when consumed in excess (Das et al.,
2010)
Sulphate is one of the important anions present in natural water and
produces laxative effect when exceeds the limit (Kasthuri et al., 2005). Sulphate
levels in the effluent were found to be 1080 mg/l. The tolerance limits prescribed
by BIS (2009) for sulphate was 1000 mg/l which was lesser than the amount
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
59
present in effluent. In a similar study done by Zahid et al. (2006), extremely
high concentrations of sodium, magnesium, chloride, calcium, sulphate and
bicarbonate were reported in tannery effluent. It was also reported by Sheela
and Peethambaram (2007) that excess amount of sulphate, nitrogen and
dissolved solids were present in the tannery effluent.
Chromium level in raw effluent was found to be 19.3 mg/l which was 10
times higher than the amount prescribed by BIS (2.0 mg/l). Chromium is the
major chemical used in tanning process and hence its discharge in the effluent
was found to be high. Continuous discharge of chromium in low concentration
has been reported to be toxic to aquatic life and has been shown to disrupt the
aquatic food chain (Fent, 2004). Extremely high concentrations of chromium,
sodium, magnesium, calcium and ammonia were detected in the tannery
effluent in a study conducted by Krantz and Kifferstein (2002).
Nickel, zinc and cadmium in the effluent were 5.5 mg/l, 10.8 mg/l and
4.2 mg/l respectively. All these metals were present in higher concentrations
compared to the prescribed limits of BIS (2009) (3.0 mg/l, 1.0 mg/l and 2.0 mg/l
respectively). The tannery wastewater is being contaminated with higher levels
of metals (iron, nickel, chromium, zinc, cadmium, manganese and copper) and
their irrigation contaminates the soil vegetables and crops, which when
consumed causes serious health hazards to the consumer (Mohanta et al.,
2010). The presence of cadmium and other heavy metals in the environment
has become a major threat to plant, animal and human life due to their toxic
effect and therefore must be removed from industrial effluent before discharge
(Vinod and Anirudhan, 2001). Deepali and Gangwar (2010) reported that the
soil and ground water samples showed the presence of high level metal
contamination due to the receipt of industrial effluent from tannery industry.
The above results indicate that the raw tannery effluent released into the
atmosphere was found to contain chemicals which were above the permissible
limit prescribed by BIS (2009). The impact of raw effluent on potable water in
the target areas was studied in the next stage.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
60
4.1.2. Biochemical profile of the target area water samples Ground water is the principal source of drinking water in urban and rural
areas of our country. The quality of drinking water in Indian cities has been
detoxified in the recent years mainly due to increase in population and improper
disposal of waste water from industries. These factors have influenced the
surface and ground water (Venkatasubramani et al., 2007). The groundwater in
industrial areas across the country has undergone severe contamination by
industrial waste, effluents and emissions which are discharged indiscriminately
without any regulatory system (Viswanatham et al., 2007). Industrial and
household waste discharged directly or indirectly, through leakages in the
sewage system enters into water sources. The changes in the properties of
water affect the biological lives in that area (Singh, 2006).
The major source of water pollution is industrial and the waste water
generated from various industries which is being discharged into common
drainage. The effluents pollute not only nearby soil but also pollute and alter the
biochemical nature of drinking water. This may be due to the presence of
chemicals in the industrial effluents which pollute and alter the biochemical
nature of drinking water (Bernal et al., 2006).
The organic waste in water may spread pathogenic diseases like
diarrhea and cholera. Along with these diseases, some long term effects can
also occur in some cases (Sathe and Kulkarni, 2001).Tannery effluent when
discharged untreated damages the normal life of receiving stream and if allowed
to percolate into the ground for a prolonged period , seriously affects the
ground water table of that locality ( Mondel et al., 2003; Prasad, 2007).
Quality of water is an important consideration in any appraisal of salinity
or alkalinity conditions in an irrigated area (Acharya et al., 2008). The water
used for drinking purpose should be free from toxic elements and excessive
amount of minerals that may be harmful to health. Keeping this in focus, to
assess the extent of ground water deterioration, a detailed analysis of ground
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
61
water quality has been carried out. Biochemical characteristics of ground water
near tannery industry area and water collected from area 15 km away from the
effluent discharge site were analysed and shown in Table 8.
TABLE 8
BIOCHEMICAL PROFILE OF TARGET AREA WATER SAMPLE
S.No Parameters Control water
Target area water sample
1 pH 7.21 8.14
2 Electrical conductivity (mho/cm) 0.65 2.88
3 Turbidity 0.05 1.28
4 Total alkalinity 600 914
5 Total suspended solids 15 418
6 Total dissolved solids 500 2467
7 Total hardness 200 830
8 Calcium hardness 75 454
9 Magnesium hardness (mg/l) 50 405
10 Fluoride 1.5 0.70
11 Chloride 600 1178
12 Chromium 0.05 10.40
13 Nickel 0.6 3.90
14 Zinc 4.5 7.00
15 Cadmium 1.9 3.40
Values are mean of triplicates
Control water- Collected from the area 15 kilometers away from the effluent discharge site
Target area water sample - Water collected within 1 kilometer radius of the effluent discharge site.
pH and Electrical conductivity (EC)
The pH of the target area water sample was 8.14 and EC was 2.88 in the
present study. The higher pH value indicates the alkaline nature of the effluent.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
62
The higher values of EC could be the result of extreme concentrations of soluble
salts from the tannery effluent discharged into the low lands and surface water
bodies of the area. Electrical conductivity and total dissolved solids are
proportional to each other (Gupta et al., 2010). The negative impact of the
effluent on the water quality includes increase in turbidity, colour, nutrient load
and presence of toxic and persistent compounds (Sharief et al., 2005).
Turbidity and Total alkalinity
Turbidity and total alkalinity were found to be increased in the target
area water sample. The total alkalinity of the water is mainly caused by the
contents of calcium, magnesium, sodium, potassium, ammonia and iron,
combined either with carbonates and/or bicarbonates or occasionally by
hydroxide (Jhingran, 2003).
Total suspended solids and Total dissolved solids Total suspended solids were found to be high in target area water sample
compared to the non contaminated water. Total dissolved solid (TDS) was one
of the often neglected parameter, eventhough it has a tremendous effect on the
overall quality of water. High TDS levels are indicative of the presence of high
levels of both inorganic and organic compounds present in the given water
sample. The total dissolved solids of the target area water sample was high
compared to the BIS value for dissolved solids which is upto 500 mg/l and the
maximum permissible quantity is 2000 mg/l (WHO, 2005). The present study
showed a level of 2467 mg/l of dissolved solids.
The high amount of dissolved solids might be due to the presence
of inorganic salts and small amounts of organic matter dissolved in
water (Lofrano et al., 2008). Jayaseelan et al. (2008) reported that the higher
concentration of total dissolved solids in surface water could be due to the
industrial activities such as tanneries, where huge amount of soluble salts are
used for processing of leather.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
63
Total hardness, calcium and magnesium hardness Hardness is one of the very important properties of ground water
from utility point of view for different purposes. It is a well known fact
that hardness is not caused by a single substance but by a variety of dissolved
polyvalent metallic ions, predominantly calcium and magnesium cations,
although cations like barium, iron, manganese, strontium and zinc also
contribute (Chaudhary et al., 2005). Calcium and magnesium are the principal
ions of hardness.
In the present study, total hardness, calcium and magnesium hardness
were found to be at a higher level in the target area water sample compared to
the control water. Calcium and magnesium causes by far the greatest portion of
the hardness occurring in the natural waters (Acharya et al., 2008). Tanning
process uses these chemicals at greater amounts in liming, pickling and bating
processes which are let out along with the effluent.
Fluoride
Fluoride enters the body through food, water, industrial exposure, drugs
and cosmetics. Presence of fluoride in water may affect the photosynthesis,
respiration and protein synthesis and enzyme activities of higher plants (Sarala
and Rao, 1993). The fluoride content in target area water sample was found to
be lesser than the control water.
Chloride
The chloride content of target area water sample recorded a value of
1178 mg/l which was twofold higher than the chloride content (600mg/l) of the
control water sample. The addition of excess sodium chloride during the tanning
process might be responsible for this.
Chromium, nickel, zinc and cadmium Chromium, nickel, zinc and cadmium were found to be high in the
target area water sample than the control water. According to World Health
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
64
Organization (2005), the metals of most immediate concern are aluminum,
CR-Control red soil, T1R-Red soil with 25% effluent, T2R-Red soil with 50% effluent, CB-Control black soil, T1B-Black soil with 25% effluent, T2B- Black soil with 50% effluent.
FIGURE 6
GERMINATION PERCENTAGE OF Vigna radiata AND Vigna mungo
CR-Control red soil, T1R-Red soil with 25% effluent, T2R-Red soil with 50% effluent, CB-Control black soil, T1B-Black soil with 25% effluent, T2B- Black soil with 50% effluent.
0
10
20
30
40
50
60
70
80
90
100
Vigna radiata Vigna mungo
Germ
inati
on
perc
en
tag
e
CR T1R T2R CB T1B T2B
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
77
FIGURE 7
VIGOUR INDEX OF Vigna radiata AND Vigna mungo
Seeds of Vigna mungo grown with 50% effluent showed a significant
reduction in germination compared to the control plants. Both the plants grown
in black soil with 50% tannery effluent showed a significant reduction in
germination percentage compared to the control plants of black soil.
A significant reduction (p< 0.05) in vigour index was observed in both the
plants grown in both the soil types using 25% and 50% effluent compared to the
control plants.
According to Malla and Mohanty (2005), there was significant decrease in
percentage germination, root length and shoot length with increase in the
effluent concentration. In their work with mung seeds, they reported that
percentage germination and the concentration of effluent treatment were
negatively correlated. Pandey et al. (2008) reported that supply of the undiluted
distillery effluent produced significant inhibition in seed germination
4.2.1.2 Root length
Table 11 shows the root length of the plants Vigna radiata and Vigna
mungo grown in red and black soils using 25% and 50% tannery effluent.
0
50
100
150
200
250
300
350
400
450
Vigna radiata Vigna mungo
Vig
ou
r in
dex
CR T1R T2R CB T1B T2B
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
78
T
AB
LE
1
1
RO
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0 ±
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Bla
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.90 ±
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7 ±
0.3
9
5.8
0 ±
0.1
8
7.3
0 ±
0.2
4
CD
( 0
.05
) 2
.92
3
.43
V
alu
es a
re m
ean ±
SD
of
trip
lica
tes
CR
- C
ontr
ol re
d s
oil,
T1R
- R
ed s
oil
with 2
5%
eff
luent,
T2R
- R
ed s
oil
with 5
0%
eff
luent, C
B-
Contr
ol b
lack s
oil,
T1B
- B
lack s
oil
with 2
5%
eff
luent,
T
2B
- B
lack s
oil
with 5
0%
eff
luent.
78
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
79
Plant biomass, root length and shoot length are used as indices of growth
performance. Tolerance to toxic elements and biotic stress depends on well
branched and extensive root systems. In our study, Vigna radiata and Vigna
mungo highlighted significant differences in their responses to various
concentrations of tannery effluent.
It was observed that both the plants recorded no significant difference in
the root length when grown with 25% effluent in both the soils. A significant
reduction in root length was observed on 90th day only when Vigna radiata was
grown with 50% effluent. The reduction might be due to the metals present in
the tannery effluent.
According to Pandey et al. (2008) supply of untreated effluent produced
significant inhibition in seed germination and seedling growth parameters in both
maize and rice. According to them a significant inhibition in root length was
observed with 50% effluent.
Studies on Allicum cepa (Palacio et al., 2005), Zea mays (Akbar et al.,
2009) and Arachis hypogea (Nagajyoti et al., 2009) showed significant decrease
in root length with higher chromium concentration in soil. The reduction in root
growth could be due to the direct contact of seedling roots with pollutants
causing a collapse and subsequent inability of the root to absorb water.
4.2.1.3. Shoot length Shoot length is considered as an important morphological parameter
related to growth and development of the whole plant.
Table 12 shows the shoot length of the plants Vigna radiata and Vigna
mungo grown in red soil and black soil using 25% and 50% tannery effluent on
30th, 60th and 90th days after sowing.
Both the plants recorded significant reduction in shoot length when grown
with 50% effluent in red soil. In black soil Vigna mungo recorded significant
reduction on the 60th day of growth.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
80
TA
BL
E 1
2
S
HO
OT
LE
NG
TH
(cm
) O
F Vigna radiata
AN
D Vigna mungo
GR
OW
N I
N R
ED
AN
D B
LA
CK
SO
ILS
US
ING
DIL
UT
ED
TA
NN
ER
Y E
FF
LU
EN
T O
N 3
0, 6
0 A
ND
90
DA
YS
AF
TE
R S
OW
ING
Vigna radiata
Vigna mungo
Da
ys
aft
er
so
win
g (
DA
S)
So
il
Gro
up
s
30
60
90
30
60
9
0
CR
2
3.0
± 2
.45
4
0.0
± 2
.42
6
8.0
± 1
.63
2
2.0
± 1
.58
3
7.0
± 2
.41
5
5.0
± 4
.08
T1
R
20
.0 ±
2.3
2
37
.0 ±
3.1
7
63
.0 ±
2.3
5
19
.0 ±
0.7
2
34
.0 ±
3.2
7
49
.0 ±
0.8
2
Re
d s
oil
T2
R
16
.0 ±
2.4
7
35
.33
± 2
.87
5
8.0
± 1
.73
1
4.0
± 3
.47
3
2.0
± 1
.43
4
7.0
± 2
.15
CB
2
1.0
± 2
.34
3
8.0
± 2
.40
5
7.0
± 2
.42
2
0.0
± 3
.24
3
7.0
± 2
.25
5
5.0
± 2
.31
T1
B
17
.0 ±
2.3
0
35
.0 ±
4.0
8
54
.0 ±
3.0
6
17
.0 ±
1.4
5
36
.0 ±
2.2
7
52
.0 ±
1.4
3
Bla
ck
s
oil
T2
B
16
.0 ±
2.1
9
34
.0 ±
3.3
2
53
.0 ±
2.6
5
16
.0 ±
1.7
4
32
.0 ±
1.6
2
51
.0 ±
1.6
0
CD
( 0
.05
) 5
.36
4
.95
V
alu
es a
re m
ean ±
SD
of
trip
lica
tes
CR
- C
ontr
ol re
d s
oil,
T1R
- R
ed s
oil
with 2
5%
eff
luent,
T2R
- R
ed s
oil
with 5
0%
eff
luent, C
B-
Contr
ol b
lack s
oil,
T1B
- B
lack s
oil
with 2
5%
eff
luent,
T
2B
- B
lack s
oil
with 5
0%
eff
luent.
80
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
81
Purohit et al. (2003) reported that the shoot length of tomato plant
decreased when the concentration of the tannery effluent was increased. Babu
and Vishnuvardhan (2006) reported that the shoot length and root length of
Vigna mungo was retarded and inhibited at higher effluent concentration.
According to Rajula and Padmadevi (2000), the germination percentage
and morphological characters like shoot length and root length decreased
gradually with increase in effluent concentration. A gradual decrease in
Effect of tannery effluent on water and soil profile, plant growth and human health
120
Dietary flavonoid makes an important contribution to health and
cardiovascular system (Lazarus et al., 2000). Flavonoids are secondary
metabolites and functions as chelators for metals (Korkina, 2007). It has a vast
array of functions in plants including antioxidant activity (Havsteen, 2002).
Tocopherol is the most important lipid soluble antioxidant and it protects
membranes from oxidation by reacting with lipid radicals produced in the lipid
peroxidation chain reaction (Traber and Atkinson, 2007). This removes the free
radicals intermediates and prevents the propagation reaction. The oxidized
α–tocopherol radicals produced in this process may be recycled back to the
active reduced form through reduction by ascorbate, retinol and ubiquinol
(Wang and Quinn, 1999).
Flavonoid content in the leaves and seeds of both the plants had a
significant increase (p<0.05) when grown with both effluent concentrations than
that of control plants. Keilig and Muller (2009) observed an increase in flavonoid
content in Arabidopsis thaliana on growth with different concentrations of
cadmium and zinc.
The tocopherol content of the T1R, T2R, T1B and T2B plants showed no
significant difference on comparison with control plants. Tocopherol content of
the seeds of T2R and T2B plants recorded a significant increase.
According to Gajewska and Sklodowska (2007), the tocopherol content
increased in shoots of wheat seedlings on treatment with nickel.
Menach et al. (2004), reported that leguminous plants are rich sources of
flavonoids. Flavonoids are postulated to play a pivotal role in adaptation of
producer legumes to their biological environments both as defensive
compounds and chemical signals in symbiotic nitrogen fixation with rhizobia
(Aoki et al., 2000)
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
121
4.2.2.4. Metal contents in various parts of Vigna radiata and Vigna mungo plants
The use of industrial effluents carrying a high load of heavy metals such
as zinc, chromium and nickel for irrigation of crops produces adverse effect on
plant growth (Pandey et al., 2008). Essential heavy metals like iron, manganese,
zinc and copper in all higher plants were found to be absorbed and accumulated
in plant tissues based on their solubility, concentration and availability of
different ions in the soil (Sharma and Chettri, 2008).
Accumulation and exclusion are two basic strategies by which plants
respond to elevated concentration of heavy metals. It is known that some plants
can survive quite well under elevated metal conditions without the hyper
accumulation characteristic. These plants appear to tolerate metals in the
environment by using a variety of mechanism including exudation of compounds
that complex metals in the contaminated environment, thereby preventing their
entry into the root (Vogel-Mikus et al., 2005).
Chromium
Chromium is known to be highly toxic to biological systems. The
morphological growth parameters like germination percentage, root length,
shoot length, fresh weight and dry weight of black gram seedling were
decreased when chromium concentration was increased (Chidambaram et al.,
2009).
Tables 27 and 28 show accumulation of chromium in roots, shoots,
leaves and seeds of the plants Vigna radiata (Figure 26) and Vigna mungo
(Figure 27) grown in red soil and black soil using 25% and 50% tannery effluent.
In 25 % effluent, the chromium content in the roots of both the plants
were found to be 4.8 mg/g and 4.6 mg/g respectively. The chromium content
was decreased to 3.84 mg/g and 2.1 mg/g in shoots which indicates the upward
translocation of chromium to shoots.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
122
T
AB
LE
27
CH
RO
MIU
M C
ON
TE
NT
(m
g/g
) IN
VA
RIO
US
PA
RT
S O
F Vigna radiata G
RO
WN
IN
RE
D S
OIL
AN
D
BL
AC
K S
OIL
US
ING
DIL
UT
ED
EF
FL
UE
NT
RO
OT
S
SH
OO
TS
L
EA
VE
S
SO
IL
C
T1
T
2
C
T1
T
2
C
T1
T
2
Re
d s
oil
0
.3 ±
0.0
1
4.8
± 0
.89
5
.4 ±
1.0
4
0.2
± 0
.01
3
.84 ±
0.5
2 4
.93 ±
0.7
5
0.1
± 0
.01
2
.53 ±
0.3
5
3.2
1 ±
0.3
9
Bla
ck
s
oil
0
.4 ±
0.0
1
4.9
± 0
.92
5
.9 ±
0.9
7
0.2
± 0
.01
3
.97 ±
0.6
3 5
.35 ±
0.9
8
0.2
± 0
.01
2
.86 ±
0.4
1
3.9
2 ±
0.4
7
CD
(0
.05
) 0
.063
0
.046
0
.53
Valu
es a
re m
ean ±
SD
of
trip
lica
tes
C-
Contr
ol soil
, T
1-
Soil
with 2
5%
eff
luent, T
2 -
So
il w
ith 5
0%
eff
luent.
See
ds : N
ot
dete
cta
ble
122
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
123
TA
BL
E 2
8
C
HR
OM
IUM
CO
NT
EN
T (
mg
/g)
IN V
AR
IOU
S P
AR
TS
OF
Vigna mungo G
RO
WN
IN
RE
D S
OIL
AN
D B
LA
CK
SO
IL U
SIN
G D
ILU
TE
D E
FF
LU
EN
T
RO
OT
S
SH
OO
TS
L
EA
VE
S
C
T
1
T2
C
T
1
T2
C
T
1
T2
Re
d s
oil
0
.6 ±
0.0
3
4.6
± 0
.8
5.3
± 0
.7
0.4
± 0
.03
2
.1 ±
0.0
3
2.9
± 0
.4
0.2
± 0
.03
1
.43 ±
0.0
2
1.5
3 ±
0.2
Bla
ck
s
oil
0
.9 ±
0.0
3
4.5
± 0
.6
6.3
2 ±
0.7
0
.5 ±
0.0
2
2.5
4 ±
0.3
4
.1 ±
0.4
0
.2 ±
0.0
3
2.2
± 0
.5
3.1
2 ±
0.4
CD
(0
.05
) 0
.063
0
.046
0
.53
Valu
es a
re m
ean ±
SD
of
trip
lica
tes
C-
Contr
ol soil
, T
1-
Soil
with 2
5%
eff
luent, T
2 -
So
il w
ith 5
0%
eff
luent.
S
ee
ds : N
ot
dete
cta
ble
123
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
124
FIGURE 26
CHROMIUM CONTENT IN VARIOUS PARTS OF Vigna radiata
FIGURE 27
CHROMIUM CONTENT IN VARIOUS PARTS OF Vigna mungo
0
1
2
3
4
5
6
7
C T1 T2 C T1 T2
mg
/ g
Root Shoot Leaf
0
1
2
3
4
5
6
7
8
C T1 T2 C T1 T2
mg / g
Root Shoot Leaf
Red soil Black soil
Red soil Black soil
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
125
Leaves of both plants recorded a value of 2.53 mg/g and 1.43 mg/g
respectively whereas chromium was not detected in grains. The same trend was
noted when the plants were grown with 50% effluent except that seed contained
negligible amounts of chromium. Calheiros et al. (2008a) reported the effect of
tannery waste water in the development of P.australis as the accumulation
of the metal in the plant was found to be in the following decreasing order
root > shoot> leaf. The concentration of chromium in the leaves, shoots and
roots increased with the concentration applied. According to Weis and Weis
(2004) the degree of upward translocation depends upon the plant species,
metal and several environmental conditions.
Several workers have documented high levels of chromium accumulation
in roots than in the top portions of the plant namely pod, leaves and stem which
was in agreement with our result (Ghosh and Singh, 2005 ; Yang et al., 2003).
Nickel
It is the essential heavy metal for plant growth and development. Under
normal conditions plants take up small quantities of nickel from soils. It can be
toxic to plants when its concentration in the soil is high. In plants under nickel
stress, the absorption of nutrients, root development and metabolism are
strongly retarded. Along with the toxicity symptoms in plants that develop later,
plant tissues are known to inhibit photosynthesis and transpiration (Zarkovic and
Blagojevic, 2009).
Tables 29 and 30 show the accumulation of nickel in roots, shoots,
leaves and seeds of the plants Vigna radiata and Vigna mungo grown in red soil
and black soil using 25% and 50% tannery effluent.
In Vigna radiata plants grown using 25 and 50% effluent, the nickel
content was found to be higher in roots compared to other parts of the plant The
value in grains was negligible. Similar trend was followed in Vigna mungo plants
also.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
126
T
AB
LE
29
NIC
KE
L C
ON
TE
NT
(m
g/g
) I
N V
AR
IOU
S P
AR
TS
OF
Vigna radiata G
RO
WN
IN
RE
D S
OIL
AN
D
BL
AC
K S
OIL
US
ING
DIL
UT
ED
EF
FL
UE
NT
RO
OT
S
SH
OO
TS
L
EA
VE
S
So
il
C
T1
T
2
C
T1
T
2
C
T1
T
2
Re
d s
oil
0
.6 ±
0.0
2 3
.01 ±
0.4
5
3.7
± 0
.56
0
.32 ±
0.0
1
2.1
± 0
.44
2
.9 ±
0.5
3
0.1
4 ±
0.0
4 1
.17 ±
0.2
5
2.5
8 ±
0.4
1
Bla
ck
s
oil
0
.9 ±
0.0
3
3.3
± 0
.61
3
.9 ±
0.7
2
0.0
7 ±
0.0
3
2.2
± 0
.34
3
.1 ±
0.3
9
0.3
± 0
.02
1
.65 ±
0.2
4
2.6
8 ±
0.2
9
CD
(0
.05
) 0
.85
0
.76
0
.37
Valu
es a
re m
ean ±
SD
of
trip
lica
tes
C-
Contr
ol soil
, T
1-
Soil
with 2
5%
eff
luent, T
2 -
So
il w
ith 5
0%
eff
luent.
S
ee
ds : N
ot
dete
cta
ble
126
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
127
T
AB
LE
30
NIC
KE
L C
ON
TE
NT
(m
g/g
) IN
VA
RIO
US
PA
RT
S O
F Vigna mungo G
RO
WN
IN
RE
D S
OIL
AN
D
BL
AC
K S
OIL
US
ING
DIL
UT
ED
EF
FL
UE
NT
RO
OT
S
SH
OO
TS
L
EA
VE
S
So
il
C
T1
T
2
C
T1
T
2
C
T1
T
2
Re
d s
oil
0
.5 ±
0.0
3
3.2
± 0
.24
3
.5 ±
0.2
7
0.3
± 0
.02
2
.9 ±
0.1
8
2.7
± 0
.21
0
.1 ±
0.0
3
1.5
4 ±
0.2
1
.68 ±
0.3
Bla
ck
s
oil
0
.8 ±
0.0
4
2.5
± 0
.21
3
.0 ±
0.2
3
0.6
± 0
.02
1
.9 ±
0.1
5
2.4
± 0
.22
0
.5 ±
0.1
1
1.4
8 ±
0.3
0
1.9
5 ±
0.4
CD
(0
.05
) 0
.34
0
.27
0
.20
Valu
es a
re m
ean ±
SD
of
trip
lica
tes
C-
Contr
ol soil
, T
1-
Soil
with 2
5%
eff
luent, T
2 -
So
il w
ith 5
0%
eff
luent.
See
ds : N
ot
dete
cta
ble
127
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
128
A similar observation was reported by Zarkovic and Blagojevic, (2009) in
their study on uptake if nickel by maize plants, where the concentration of nickel
was 8 times higher in roots than in shoots
Metals in tannery waste water occur in a complex form and vary in their
availability to the plant parts (Gupta and Sinha, 2007).
Zinc
Zinc is an essential micronutrient for all organisms and form active site for
various metalloenzymes. Excessive intake of zinc may lead to vomiting,
dehydration and other adverse effects. Industrial waste water rich in zinc
cadmium, chromium and other heavy metals pose a major threat to the
agricultural fields.
The plants irrigated with diluted form of industrial effluent do not face
much hazards as with the raw effluent which contains the heavy metals at a
higher concentration.
Tables 31 and 32 show the accumulation of zinc in roots, shoots, leaves
and seeds of the plants Vigna radiata and Vigna mungo grown in red soil and
black soil using 25% and 50% tannery effluent
Zinc contents of the plant Vigna radiata and Vigna mungo in various parts
were found to be higher than that of the control plants. Zinc content was higher
in roots but negligible in grain. The accumulation of zinc followed a decreasing
order from roots, shoots, leaves and grain.
Khilji and Barbeen (2008) observed the percentage reduction in the
amount of metals in different concentrations of tannery sludge after growing
H. Umbellata for 90 days. Akinola and Ekiyoyo (2006) studied that accumulation
of cadmium, lead and chromium in crop plants were high in roots compared to
other parts.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
129
T
AB
LE
31
ZIN
C C
ON
TE
NT
(m
g/g
) IN
VA
RIO
US
PA
RT
S O
F Vigna radiata G
RO
WN
IN
RE
D S
OIL
AN
D
BL
AC
K S
OIL
US
ING
DIL
UT
ED
EF
FL
UE
NT
RO
OT
S
SH
OO
TS
L
EA
VE
S
So
il
C
T1
T
2
C
T1
T
2
C
T1
T
2
Re
d s
oil
0
.7 ±
0.0
2
4.2
± 0
.45
5
.1 ±
0.6
3
0.6
± 0
.02
3
.4 ±
0.2
5
2.2
5 ±
0.0
2 0
.48 ±
0.0
3
1.3
7 ±
0.1
4
1.0
± 0
.21
Bla
ck
s
oil
0
.8 ±
0.0
2
4.5
± 0
.71
4
.9 ±
0.8
2
0.6
± 0
.03
3
.6 ±
0.2
9
3.9
± 0
.32
1
.54 ±
0.1
2
1.3
± 0
.13
2
.9 ±
0.1
9
CD
(0
.05
) 0
.91
0
.58
0
.20
Valu
es a
re m
ean ±
SD
of
trip
lica
tes
C-
Contr
ol soil
, T
1-
Soil
with 2
5%
eff
luent, T
2 -
So
il w
ith 5
0%
eff
luent.
See
ds : N
ot
dete
cta
ble
129
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
130
T
AB
LE
32
ZIN
C C
ON
TE
NT
(m
g/g
) IN
VA
RIO
US
PA
RT
S O
F Vigna mungo
GR
OW
N I
N R
ED
SO
IL A
ND
BL
AC
K S
OIL
US
ING
DIL
UT
ED
EF
FL
UE
NT
RO
OT
S
SH
OO
TS
L
EA
VE
S
So
il
C
T1
T
2
C
T1
T
2
C
T1
T
2
Re
d s
oil
0
.8 ±
0.0
3
4.9
± 0
.53
5
.6 ±
1.7
3
0.7
± 0
.04
3
.9 ±
0.3
2
4.8
± 0
.41
0
.56 ±
0.0
4
1.3
3 ±
0.1
5
1.7
2 ±
0.1
6
Bla
ck
s
oil
0
.9 ±
0.0
4
4.7
± 0
.62
5
.1 ±
1.8
1
0.7
± 0
.03
3
.8 ±
0.2
9
4.1
± 0
.22
0
.57
± 0
.12
2
.10 ±
0.1
9
2.1
8 ±
0.2
0
CD
(0
.05
) 0
.89
0
.61
0
.18
Valu
es a
re m
ean ±
SD
of
trip
lica
tes
C-
Contr
ol soil
, T
1-
Soil
with 2
5%
eff
luent, T
2 -
So
il w
ith 5
0%
eff
luent.
S
ee
ds : N
ot
dete
cta
ble
130
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
131
Cadmium
Cadmium is one of the most toxic heavy metals and is recognized for its
negative effect on the environment where it accumulates throughout the food
chain posing a serious threat to human health (Xiaomei et al., 2004).The uptake
of cadmium by roots and transport to the upper parts takes place in the upward
translocation mechanism (Huttova et al., 2006).
Cadmium has been recognised to have a negative impact on the
environment in high concentration. The presence of excessive amount of
cadmium in soil causes reduction in root growth, disturbance in mineral nutrients
and carbohytrate metabolism. They were found to reduce biomass production
due to the direct consequence of the inhibition of chlorophyll synthesis and
photosysnthesis. The stress caused by cadmium and zinc in the tannery effluent
could be reduced by diluting the effluent before application on the vegetative
crops.
Table 33 and 34 show the accumulation of cadmium in roots,
shoots, leaves and seeds of the plants Vigna radiata and Vigna mungo grown in
red soil and black soil using 25% and 50% tannery effluent.
Cadmium content in various plant parts of Vigna radiata in 50% effluent
in the present study was found to have the following order of accumulation as
3.1 mg/g, 2.5 mg/g and 2.25 mg/g in root, shoot and leaves respectively. But it
was not detectable in grains. The same trend was noticed in Vigna mungo
plants.
According to Sharma and Chettri (2008) cadmium and lead were found
to have accumulated in plant tissues. Although cadmium adversely affects plant
growth, root growth is severely affected and results in faster reduction of root
biomass compared to the shoot resulting in an increased shoot root biomass
ratio (Chandra et al., 2010).
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
132
TA
BL
E 3
3
CA
DM
IUM
CO
NT
EN
T (
mg
/g)
IN V
AR
IOU
S P
AR
TS
OF
Vigna radiata G
RO
WN
IN
RE
D S
OIL
AN
D B
LA
CK
SO
IL U
SIN
G D
ILU
TE
D E
FF
LU
EN
T
RO
OT
S
SH
OO
TS
L
EA
VE
S
So
il
C
T1
T
2
C
T1
T
2
C
T1
T
2
Re
d s
oil
1
.05 ±
0.1
1
2.8
± 0
.19
3
.1 ±
0.2
1
0.8
2 ±
0.0
7 2
.27 ±
0.1
6
2.5
± 0
.24
0
.24 ±
0.0
5
1.9
± 0
.14
2
.25 ±
0.2
5
Bla
ck
s
oil
1
.09 ±
0.1
4
2.9
± 0
.16
3
.9 ±
0.2
7
0.7
± 0
.05
2
.8 ±
0.1
9
3.1
± 0
.29
0
.31
±0
.12
1
.8 ±
0.1
5
2.9
0 ±
0.2
3
CD
(0
.05
) 0
.25
0
.31
0
.26
Valu
es a
re m
ean ±
SD
of
trip
lica
tes
C-
Contr
ol soil,
T1-
So
il w
ith 2
5%
eff
luent, T
2 -
So
il w
ith 5
0%
eff
luent.
S
ee
ds : N
ot
dete
cta
ble
132
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
133
T
AB
LE
34
CA
DM
IUM
CO
NT
EN
T (
mg
/g)
IN V
AR
IOU
S P
AR
TS
OF
Vigna mungo G
RO
WN
IN
RE
D S
OIL
AN
D
BL
AC
K S
OIL
US
ING
DIL
UT
ED
EF
FL
UE
NT
RO
OT
S
SH
OO
TS
L
EA
VE
S
So
il
C
T1
T
2
C
T1
T
2
C
T1
T
2
Re
d s
oil
1
.04 ±
0.0
7 2
.35 ±
0.1
2
3.8
± 0
.32
0
.71 ±
0.1
1 2
.2 ±
0.0
9
2.7
± 0
.18
0
.03 ±
0.9
6
1.3
1 ±
0.2
4
2.1
2 ±
0.4
1
Bla
ck
s
oil
1
.0 ±
0.0
3
3.0
± 0
.24
3
.6 ±
0.3
5
0.8
± 0
.10
2
.85 ±
0.1
2
3.0
± 0
.20
0
.64 ±
0.0
9
2.1
3 ±
0.2
9
2.6
2 ±
0.3
6
CD
(0
.05
) 0
.44
0
.23
0
.45
Valu
es a
re m
ean ±
SD
of
trip
lica
tes
C-
Contr
ol soil,
T1-
So
il w
ith 2
5%
eff
luent, T
2-
So
il w
ith 5
0%
eff
luent.
See
ds : N
ot
dete
cta
ble
133
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
134
Stolt et al. (2006) opined that the rate of absorption and translocation of
cadmium varies from plant to plant and genetic variation exists in the
accumulation rate of cadmium in different parts of the plant.
Low grain cadmium accumulation was observed in many studies. The
mechanism of cadmium uptake, translocation and grain accumulation depends
on lower cadmium pools in leaves. Much of the cadmium was found to be
retained in the root cell walls during the growth with 25% effluent
The gradient of accumulation of heavy metals was found to be highest in
roots followed by stem, branches, leaves and then in grains or fruits as reported
by Sharma and Agrawal (2005). Fritioff and Gregor (2006) in their study on
distribution of heavy metals such as zinc, copper, lead and cadmium by leaves,
stems and roots of Potamogeton natans, found the highest accumulation in
roots than other parts in conformity with the present study. Angelova and Ivanov
(2008), in the work on distribution of heavy metals in Brassica Nigera, reported
that the metal content of the seeds were lower in comparision to other parts. It
follows the order roots> stems> leaves>fruit shells> seeds. Fruit shells act as a
barrier on their way towards the seeds.
In accordance with these observations the concentration of metals in our
study were found to be higher in roots followed by shoots and leaves, with least
concentrations in grain. The seed coat of the grains might have acted as a
barrier in Vigna radiata and Vigna mungo in condtions of soil contamination.
4.2.3. Histochemical observations of root sections of the selected plants
Plate 7 show the cross sections of root of Vigna radiata and Plate 8 show
that of Vigna mungo plants grown in 25% and 50% tannery effluent.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
135
PLATE 7
HISTOCHEMICAL OBSERVATION OF ROOTS OF Vigna radiata
CR- Control with red soil, T1R- Red soil with 25% effluent, T2R- Red soil with 50% effluent, CB- Control black soil, T1B- Black soil with 25% effluent, T2B- Black soil with 50% effluent
CB
T1B
T2B
CR
T1R
T2R
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
136
PLATE 8
HISTOCHEMICAL OBSERVATION OF ROOTS OF Vigna mungo
CR- Control with red soil, T1R- Red soil with 25% effluent, T2R- Red soil with 50% effluent, CB- Control black soil, T1B- Black soil with 25% effluent, T2B- Black soil with 50% effluent
C1R C1B
T1R T1B
T2R T2B
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
137
Localization of metals in various plant tissues and the concerned
anatomical variations in effluent cultivated plants was done by histochemical
staining method.
Both the plants grown with 25% effluent (T1R and T1B) did not show any
accumulation in their root tissues. Roots of T2R and T2B Vigna radiata plants
exhibited accumulation of heavy metal. Similarly the Vigna mungo plants grown
with 50% effluent (T2R and T2B) were found to have accumulations of metals in
the cross sectional study of roots.
It was observed that there were many sites of accumulation in the roots
of Vigna mungo plant compared to the roots of Vigna radiata plants indicating
that metals are fast absorbed in Vigna mungo plants than Vigna radiata plants.
An important reason for enhanced accumulation of chromium in the root may be
due to presence of organic acids in the root exudates which form complexes
with chromium, thereby making them available for the uptake by the root.
Histological changes in the root showed highly distorted piliferous layer
and cortex. Thickened cell walls of vessels and pith were noted. The distortion
of cells of various tissues may be the result of interferences with the cell division
or with cell elongation.
Though metal concentrations were found in leaves and shoots of both the
plants, the histochemical sections did not show any accumulation. As Shankar
et al. (2005) suggested, translocation of chromium from root to shoot is slow.
Pulford et al. (2001) in a study with temperate trees confirmed that chromium is
poorly taken up into the aerial parts and is predominantly held in the roots.
In our study, in both the species of Vigna chromium accumulation was
high in the roots compared to the stems, leaves and grains which was in
concomitment with the results obtained by Chandra et al. (2010).
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
138
4.2.4. Yield parameters
a. Number of nodules In nodulating plants, nitrogen fixation is the primary route of nitrogen
nutrition and hence what happens to the nodules at the stimulated growth
conditions will have a profound effect on the overall growth of the plants
themselves. Leguminous plants exhibit differential response in nodulation to
heavy metal toxicity (Veliappan et al., 2002).
Table 35 and 36 show the number of nodules formed in plants Vigna
radiata and Vigna mungo grown in red soil and black soil using 25% and 50%
effluent concentrations respectively.
TABLE 35
NUMBER OF NODULES OF Vigna radiata GROWN IN RED SOIL
AND BLACK SOIL USING DILUTED EFFLUENT
Vigna radiata
Days after sowing (DAS) Soil Groups
30 60 90
C1 10.0 ± 4.08 19.0 ± 0.82 21.0 ± 0.80
T1 9.0 ± 0.82 18.0 ± 0.81 20.0 ± 0.82 Red soil
T2 8.0 ± 1.63 17.0 ± 0.82 19.0 ± 0.80
C2 11.0 ± 0.82 18.0 ± 1.63 19.0 ± 1.60
T3 10.0 ± 0.82 16.0 ± 6.24 16.0 ± 1.63 Black soil
T4 9.0 ± 0.82 13.3 ± 2.45 16.0 ± 0.82
CD ( 0.05) 4.2
Values are mean ± SD of triplicates
CR- Control with red soil, T1R- Red soil with 25% effluent, T2R- Red soil with 50% effluent, CB- Control black soil, T1B- Black soil with 25% effluent, T2B- Black soil with 50% effluent
Number of nodules were increased with increase in the time point and
reached a maximum level on 60th day and sustained till 90th day in both the
plants. According to Geetha et al. (2008), the nodule formation in soybean
reached its peak during flowering stage and senescence of nodules occurred as
the plant matured.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
139
TABLE 36
NUMBER OF NODULES OF Vigna mungo GROWN IN RED SOIL
AND BLACK SOIL USING DILUTED EFFLUENT
Vigna radiata
Days after sowing (DAS) Soil Groups
30 60 90
C1 11.0 ± 1.63 15.0 ± 4.08 16.0 ± 1.63
T1 9.0 ± 0.79 13.0 ± 2.45 14.0 ± 3.27 Red soil
T2 8.0 ± 0.82 12.0 ± 1.63 13.0 ± 2.45
C2 12.0 ± 1.61 16.0 ± 1.63 16.0 ± 0.82
T3 11.0 ± 4.08 15.0 ± 3.27 14.0 ± 3.25 Black soil
T4 10.0 ± 0.80 14.0 ± 4.08 13.0 ± 2.45
CD ( 0.05) 5.1
Values are mean ± SD of triplicates
CR- Control with red soil, T1R- Red soil with 25% effluent, T2R- Red soil with 50% effluent, CB- Control black soil, T1B- Black soil with 25% effluent, T2B- Black soil with 50% effluent
b. Flowering time
Table 37 shows the day of first flowering of the plants Vigna radiata and
Vigna mungo grown in red soil and black soil using 25 % and 50% tannery
effluent.
TABLE 37
FLOWERING TIME OF PLANTS Vigna radiata AND Vigna mungo GROWN IN RED SOIL AND BLACK SOIL USING DILUTED EFFLUENT
Flowering time Soil Groups
Vigna radiata Vigna mungo
CR 45 ±4.08 45 ± 4.04
T1R 47 ±0.82 47 ± 1.63 Red soil
T2R 49 ±0.80 49 ± 0.86
CB 44 ±3.27 45 ± 4.05
T1B 47± 0.85 46 ± 0.82 Black soil
T2B 49 ±0.81 48 ± 1.62
CD ( 0.05) 4.9
Values are mean ± SD of triplicates
CR- Control with red soil, T1R- Red soil with 25% effluent, T2R- Red soil with 50% effluent, CB- Control black soil, T1B- Black soil with 25% effluent, T2B- Black soil with 50% effluent
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
140
There was no significant delay in flowering time of Vigna radiata and
Vigna mungo plants grown using both the effluents in both the soils.
c. Pod length, Pod weight, Number of Pods/plant Table 38 shows the pod length and pod weight of the plant of Vigna
radiata and Vigna mungo grown in red soil and black soil using 25% and 50%
tannery effluent.
Vigna radiata recorded significant (p<0.05) reduction in pod length grown
with black soil and 50% effluent. The pod weight of Vigna mungo was
decreased significantly with 50% effluent.
TABLE 38
POD LENGTH, POD WEIGHT OF Vigna radiata AND Vigna mungo GROWN IN RED AND BLACK SOILS USING DILUTED
CR- Control with red soil, T1R- Red soil with 25% effluent, T2R- Red soil with 50% effluent, CB- Control black soil, T1B- Black soil with 25% effluent, T2B- Black soil with 50% effluent
Table 39 shows number of pods/ plant of Vigna radiata and Vigna mungo
grown in red soil and black soil using 25% and 50% tannery effluent.
A significant decrease was not observed in number of pods/plant in both the
plants and soils.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
141
TABLE 39
NUMBER OF PODS / PLANT OF Vigna radiata AND Vigna mungo GROWN IN RED AND BLACK SOILS USING DILUTED
TANNERY EFFLUENT
Pod length (cm) Soil Groups
Vigna radiata Vigna mungo
CR 4.70 ± 0.16 1.42 ± 0.02
T1R 4.50 ± 0.41 1.30 ± 0.04 Red soil
T2R 4.40 ± 0.31 1.23 ± 0.03
CB 4.50 ± 0.43 1.31 ± 0.01
T1B 4.10 ± 0.09 1.28 ± 0.02 Black soil
T2B 3.90 ± 0.05 0.99 ± 0.01
CD ( 0.05) 0.5
Values are mean ± SD of triplicates
CR- Control with red soil, T1R- Red soil with 25% effluent, T2R- Red soil with 50% effluent, CB- Control black soil, T1B- Black soil with 25% effluent, T2B- Black soil with 50% effluent
d. Number of seeds / plant and Number of seeds /pod Table 40 shows the number of seeds /plant and number of seeds /pod of
Vigna radiata and Vigna mungo plants grown in red soil and black soil using
25% and 50% tannery effluent.
The decrease in the number of seeds/ plant and number of seeds / pod in
effluent treated Vigna radiata and Vigna mungo plants grown in red and
black soils was not found to be significant compared to the control plants.
Sinha et al. (2008) demonstrated that V.radiata exhibited a significant increase
in growth parameters when grown on lower amendments of sludge.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
142
TABLE 40
NUMBER OF SEEDS /PLANT AND NUMBER OF SEEDS /POD OF Vigna radiata AND Vigna mungo GROWN IN RED AND BLACK SOILS
USING DILUTED TANNERY EFFLUENT
Number of seeds /plant Number of seeds /pod Soil Groups Vigna
CR- Control with red soil, T1R- Red soil with 25% effluent, T2R- Red soil with 50% effluent, CB- Control black soil, T1B- Black soil with 25% effluent, T2B- Black soil with 50% effluent.
e. Total seed weight / plant and 100 seed weight
Table 41 shows the total seeds weight / plant and 100 seeds weight of
Vigna radiata and Vigna mungo plants grown in red soil and black soil in 25%
and 50% tannery effluent.
Total seeds weight / plant of Vigna radiata and Vigna mungo showed no
significant reduction when grown in 25% and 50% effluent. This indicates that
the diluted tannery effluent might be used for plant growth. 100 seed weight of
both the plants were found to be significantly decreased with 50% effluent in
both the soils.
Results of yield parameters of both the plants grown in red soil and black
soil in both the effluent concentrations indicated that plants grow better in 25%
tannery effluent and diluted effluent could be a better choice for plant growth in
industrialized area.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
143
TABLE 41
TOTAL SEED WEIGHT/ PLANT AND 100 SEED WEIGHT OF Vigna radiata
AND Vigna mungo GROWN IN RED AND BLACK SOILS USING
DILUTED TANNERY EFFLUENT
Total seed weight/ plant (g) 100 seed weight (g) Soil Groups Vigna
CR- Control with red soil, T1R- Red soil with 25% effluent, T2R- Red soil with 50% effluent, CB- Control black soil, T1B- Black soil with 25% effluent, T2B- Black soil with 50% effluent
Hence, from the results of this phase it was found that the biometric
observations and biochemical parameters such as chlorophyll, carbohydrate,
carotenoid, ascorbic acid and yield parameters of the plants grown in red soil
were at higher levels compared to those grown in black soil. Vigna radiata
showed a better response with respect to biometric observations and certain
biochemical parameters compared to Vigna mungo. Plants grown with 25%
effluent exhibited a better growth compared to those grown with 50% effluent.
PHASE III
4.3. Health profile of Tannery workers Any effort to evaluate occupational health risks includes assessing the
health of individual workers with the goal of keeping the worker healthy and
reducing the overall risks in the work environment.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
144
A worker is at risk if he/she has a greater chance of developing disease
than a non exposed worker. It is very important to identify all harmful
substances and to monitor and control exposures in order to manage the risk
(Hall, 2001).
Leather production includes many operations with different exposures,
which can be harmful for the health of the workers and particularly be
carcinogenic (Issever et al., 2007). Certain chemicals such as benzene based
dyes and formaldehyde are considered to be carcinogenic (Budhwar, 2005).
Besides these, scores of other chemicals and organic solvents such as
chromate and bichromate salts, aniline, butyl acetate, ethanol, benzene,
toluene, suplhuric acid and ammonium hydrogen sulfide are used in the
tannery industry. An important health risk factor for the tannery workers is
occupational exposure to chromium mainly in organic form or in protein bound
form caused by leather dust (Mikoczy and Hagmar, 2005). Chromium may
enter the body by inhalation, ingestion and by direct cutaneous contact.
Professional exposure to chromium increases the risk of dermatitis, ulcers and
perforation of the nasal septum and respiratory illness as well as increased lung
and nasal cancers. Chromium specific health hazards like carcinoma of the
larynx and lung parenchyma and paranasal sinusis have also been reported
(Rastogi et al., 2007).
According to Bulletin of the WHO (2005), 58% of the tannery workers
were found to suffer from gastrointestinal diseases, 31% from dermatological
diseases, 12% from hypertension and 0.9 % from jaundice.
Working conditions, nature of work, vocational and professional status
and geographical location of industries and employment have a profound
impact on the social status and social well being of the workers (Babalola and
Babajide, 2009)
Exposure is the contact of toxic substance by the body. It may be acute
(immediate) or chronic (long term). During leather tanning, the workers are
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
145
exposed to chemicals such as sodium chloride during soaking stage, sulphide
and lime in fleshing and trimming stage, acid and ammonium salts in bating
stage, fungicides and bactericides in picking stage, chromium salts during
tanning stage, nickel, arsenic, zinc, cadmium, copper, dye, and solvents
during wet finishing stage. The chemicals used in the process of tanning have
been proved to be toxic.People involved in producing leather have a
significant risk of presenting clinical conditions attributed to chromium exposure
(Cuberos et al., 2009).
The use of sulphides and hydrosulphides in dehairing operations may
carry a risk of skin contact for the operator. A similar risk is possible in the use of
caustic materials such as sodium hydroxide or calcium hydroxide causing skin
burns. Formaldehyde, glutaraldehyde and hydrogen peroxide used in tanning
processes causes irritation of body tissues even in if minute quantities are
inhaled. A variety of dyestuffs and fungicides are used which are quite serious if
inhaled or injested (Taylor et al., 2006).
Continuous exposure to these chemicals results in entry into the body.
Workers who have been dealing with these chemicals and who do not follow
any safety measures in preventing the entry of the chemicals into the body,
were found to acquire many forms of ill effects. Eating in contaminated area,
using the chemicals with bare hand, breathing without using mask in the
workplace are some of the reasons of the entry of these hazardous chemicals.
Hence in this phase of the present study an attempt was made to analyze
the biochemical parameters associated with hepatic, renal and skin disorders
caused, if any in the selected group tannery workers who have been exposed to
these chemicals for many years and who do not follow any safety measures
while using the chemicals.
Tannery workers with one to five years of experience (Group II: n=20)
and workers with five to ten years of experience (Group III : n= 20), were
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
146
selected for the study. A reference group of 20 subjects belonging to the similar
age group who never had any occupational exposure in the tanneries served as
control (Groiup I). Each group comprised of 60% men and 40% women workers
who belong to the same socio economic group and dietary pattern. They
belonged to an age group of 20-50 years and they were under cumulative
exposure to numerous pollutants in the workplace. They had no history of
defect, infections or metabolic disorders. These workers were not engaged in
any other occupation and hence not exposed to other types of pollutants.
Hematological parameters (hemoglobin, total count and
immunoglobulin E), assessment of liver function (alanine transaminase,
aspartate transamiase, alkaline phosphatase, acid phosphatase and lactate
dehydrogenase), assessment of renal function (urea, uric acid and creatinine)
and mineral status (chromium, nickel, zinc and cadmium) of the selected
tannery workers were performed and their results are discussed as follows.
4.3.1 Hematological parameters of blood sample
Hematological parameters are related to the changing environmental
conditions and therefore can be used to screen the health state of organisms
exposed to a particular toxicant (Tripathi et al., 2002).
4.3.1.1. Hemoglobin and total leukocyte count
The mean values of hemoglobin and total leukocyte count estimated in
control and experimental groups are presented Table 42 and Figure 28 and
Figure 29.
The normal hemoglobin level is 12-14 g/dl. Group I participants
(control) had hemoglobin contents within the normal limits, whereas group II and
group III recorded significantly lower levels than the control. The total count of
the experimental groups was found to be increased than that of the control
groups.
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
147
0
2000
4000
6000
8000
10000
12000
14000
Group I Group II Group III
To
tal
leu
co
cy
te c
ou
nt
(mm
3)
0
2
4
6
8
10
12
14
16
Group I Group II Group III
Hem
og
lob
ulin
(g
/100m
l)
TABLE 42
HEMOGLOBIN CONTENT AND TOTAL LEUKOCYTE COUNT OF THE TANNERY WORKERS
Groups Hemoglobin (g/100 ml)
Total leukocyte count (mm3)
Group I
Control 12.33 ± 0.08 10,100 ± 105.7
Group II
1-5 years 9.60 ± 0.7 11,000 ± 104.9
Group III
5-10 years 7.87 ± 0.9 12,320 ± 96.2
CD (0.05) 0.19 112.57
Values are presented as mean± SD (n = 20 in each group)
The reduction
of hemoglobin content might
be due to the effect of
pollutants on hematopoietic
system which leads to
anemic condition in
human (Mathivanan, 2004).
Hematological values such
as white blood cell count and
red blood cell count of population residing in industrial area exposed to toxic
pollutants showed an
increased trend while
the hemoglobin content
decreased in exposed
population compared to
the non exposed
population (Ahsan, 2003).
According to Benova et al.
(2002), chromium is rapidly
FIG. 28 HEMOGLOBIN CONTENT
FIG. 29 TOTAL LEUKOCYTE COUNT
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
148
absorbed by the lungs into the blood and easily penetrates the cellular
membranes and binds to the hemoglobin in the red blood cells, thereby affecting
the oxygen carrying capacity and impairing the lung function status.
Elevated leucocyte count might be due to increase in the population
of neutrophils, acidophils and basophils (Joshi et al., 2002). Cases of
hematological effects have been reported in humans after the ingestion of lethal
or sublethel doses of chromium. Decreased hemoglobin (anemia) content and
increased total white blood cell count (thrombocytopenia) were noted by
Parveen and Rawat (2010). Alterations in blood hemoglobin, total cell count
and erythrocyte sedimentation have provided a useful means of detecting
and assessing the severity of anemia due to exposure to toxic pollutants
(Sharma et al., 2004).
4.3.1.2 Immunoglobulin E levels
Table 43 and Figure 30 shows the Immunoglobulin E levels in blood
sample of the participants.
TABLE 43
Ig E LEVELS OF THE WORKERS
Groups IgE (IU/L)
Group I 98.6± 1.3
Group II 732± 1.9
Group III 800± 2.3
CD ( 0.05) 4.8
Values are presented as mean± SD (n = 20 in each group)
The results show that both the experimental groups had significantly
increased levels of Immunoglobin E compared to the Group I (control)
participants. For any allergic reactions, elevated Ig E is an important
determinant. Occupational exposure and elevated serum Ig E levels were well
correlated in the study conducted by Kim et al., (2010).
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
149
0
100
200
300
400
500
600
700
800
900
Group I Group II Group III
Imm
un
og
lob
ulin
(IU
/ L
)
Sensitizers are agents
that may cause allergic or
allergic-like responses to
occur. After an initial
exposure to a substance an
individual may become
sensitized to that substance.
Subsequent exposures to
the same substance, often at
a much lower concentration than before, produce an allergic response. This
response may be a skin rash (dermatitis) or an asthmatic-like attack, depending
on the route of exposure (Shahzad et al., 2008).
Leather tanning is principally chemical preservation of raw hide by the
process in which binding of various chemicals (mainly chromium salts as
potassium dichromate) to proteins in raw hide takes place. Chromium has
potential to bind with skin proteins of tannery workers to produce complex
antigens which lead to hypersensitivity. The resulting contact dermatitis could be
preliminary condition to the development of bronchial asthma (Lockman, 2002).
Tannery workers are thus potentially exposed to harmful agents,
rendering them vulnerable to health problems especially those of skin and
gastrointestinal problems. Due to this exposure, health hazards namely eye
irritation and repiratory tract irritation would be caused. Skin ulcer might develop
if chromium compounds come into contact with an abrasion, a scratch of
laceration of the skin (Shahzad et al., 2006).
In the present study, 12 out of 20 persons of groups III who had more
years of exposure were found to possess skin rashes and scales indicating
allergic response. All the respondents were associated with chrome tanning
process. They handle lead chromate and nickel chromate every day. And their
contact with these chemicals occurs for more than 6 hours a day. The route of
FIG. 30 Ig E LEVELS OF THE WORKERS
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
150
entry was mainly absorption by skin contact since they seldom wore gloves
while operating the chemicals. Other possible routes of entry were inhalation of
chrome dust and ingestion since they have lunch in the work place itself without
proper handwash. Repeated contact with toxic metals might be the cause for
allergic contact dermatitis.
Plate 9 shows a person affected by dermatitis. He was associated with all
the processes of tanning since he has 18 years of experience in tannery
industry. His Ig E levels were found to be increased than the normal limits and
had skin allergy. This person was associated with all the process of tanning. He
handled chemicals namely chrome, formate and potassium dichromate daily.
PLATE 9
DERMATITIS LIKE SYMPTOM
In a study conducted by Rastogi et al. (2008), the leather tanners who
had a mean exposure of 8 years in the tanneries were found to have
dermatological diseases such as rashes and papules along with complaints of
itching. The burning sensation was also reported by 15 subjects in the exposed
workers. Chromium toxicity can produce penetrating lesions known as chrome
hole or chrome ulcers particularly in areas where a break in the epidermis is
Results and Discussion
Effect of tannery effluent on water and soil profile, plant growth and human health
151
already present. These commonly occur on the fingers, knuckles, and fore
arms. The characteristic chrome sore begins as a papule forming an ulcer with
raised hard edges. Ulcers can penetrate deep into soft tissue or become the
sites of secondary infection (Meditext, 2005). Chrome ulceration is a specific
skin lesion caused as a result of direct contact with trivalent or hexavalent
chromium compounds and is especially observed among chrome tanners.
The affected workman has painless, multiple ulcers of holes on the skin
of the exposed parts of the body, especially hands and feet. In a study
conducted in North India, the prevalence of ulcers of fingers and toes among
chrome tanners was found to be 10.6% (Raidas, 2007).
The most viable condition that aggravates the risk of developing
dermatitis is the constant wetting of the skin. Persons who are engaged in
soaking operations were found to be maximum affected (10.46%) with
dermatitis.
4.3.2. Assessment of liver function
Clinical laboratories use the measurement of alanine transaminase