Pesticide Residues in Fish - Pesticides: Evaluation of Environmental Pollution - page 368

program for the safety evaluation to consumers, the situation may rise to an alarming
level (Amorastt et al. 1983).
The National Institute of Oceanography, India, conducted several studies on chlorinated
hydrocarbons in marine biota from the Indian region. Zooplankton and bottom-feeding
fish (four species) from the Bay of Bengal were studied in the vicinity of the Coleroon River
mouth and from the northern Bay of Bengal. Total DDT concentrations ranging from 1.31
to 115.9 ng/g w/w in different fish species and 4.0 to 1587.8 ng/g w/wt in zooplankton
were found. Aldrin levels were 0.32 to 4.23 ng/g in the fish tissue and ND to 0.78 ng/g in
zooplankton (Shailaja and Singhal 1994).
Levels of total DDT in marine fish from different landing centers along the Tamil Nadu
and Pondicherry coasts on the southeast coast of India were from ND to 2.38 ng/g (Rajendran
et al. 1992). Out of four species of marine fish, the concentration of pesticide residues was
highest in black pomfret fish ( Parastromateus niger ), containing 0.0003 mg/kg heptachlor,
0.09 mg/kg aldrin, 0.001 mg/kg dieldrin, 0.004 mg/kg endrin, 0.003 mg/kg p,p′-DDE, 0.002
mg/kg p,p′-DDD, 0.007 mg/kg o,p′-DDT, and 0.042 mg/kg p,p′-DDT (Radhakrishnan and
Antony 1989). The concentration of pesticides increases in marine biota in the monsoon sea-
son (Shailaja and Nair 1997; Shailaja and Sengupta 1989).
In other studies, DDT was reported from 3 to 128 ng/kg in marine biota (Nigam et al.
1998). DDT and its metabolites, HCH isomers, chlordane compounds, and HCB were deter-
mined in river dolphin blubber and prey fish collected during 1993-1996 from the river,
Ganges, in India (Senthil Kumar et al. 1999). The DDT metabolites in blubber (21,000-64,000
ng/g ww) were the predominant compounds found in dolphin tissues and fish that consti-
tute the diet of dolphins. The levels of chlordane compounds and HCB in dolphin blubber
were 860-1,900, 45-240, and 7.7-19 ng/g ww, respectively. The concentrations in fish were
3-13 ng/g ww for chlorinated compounds, respectively. Compared to the levels of total
DDT, chlordane, and HCB observed during 1988-1992 (Kannan et al. 1994), the levels in
1994-1996 were doubled for all the compounds except HCB (Senthil Kumar et al. 1999).
An investigation was conducted from 2001 to 2005 for determining the residual concen-
tration of five pesticides, namely total-HCH, total-DDT, total-endosulfan, dimethoate, and
malathion in fish samples collected from various points of the river Ganga. It was found
that total-HCH concentration remains above the MRL values for maximum number of
times in comparison to four other pesticides. The pesticide contamination to fish may be
due to indiscriminate discharge of polluted and untreated sewage sludge to the river. The
pesticide contents in some places are alarming (Md. Wasim Aktar et al. 2009).
An analysis of four fish species from a freshwater lake in Jaipur, India, revealed that the
residues of aldrin and DDT were low in muscle tissue compared to other tissues (Bakre
et al. 1990). The levels of total DDT in the brain averaged 0.82-12.84 μg/g (Bakre et al. 1990).
In 1999, freshwater fish were analyzed for pesticide residues in three ICAR (Indian
Council of Agricultural Research) centers in India. Out of 36 samples collected from
Kerala, none of the samples contained residues of DDT, whereas all the 37 samples col-
lected from Assam contained DDT. Similarly, none of the 9 samples collected from Andhra
Pradesh contained DDT. In Kalyani, West Bengal, 48 samples of the fish Rohu and Catla
collected from Calcutta market were examined, and 36 samples (75%) were contaminated
with DDT residues; 14 samples (29.2%) exceeded the MRL value. In Coimbatore, out of 12
samples of common small fish, 75% of the samples contained DDT. In Vellayani, sea fish
such as Mackerel and Salmon from the market were monitored over a period of 12 months
and none of the samples contained any detectable residue (ICAR 2002).
As part of a larger study assessing contamination status of inland wetlands of India,
a study was conducted to evaluate OCP residues in fish collected from different inland