Milk and meat are the basic foods in the human diet and these can carry numerous xenobiotic substances (pesticides, disinfectants, drugs, metals and various environmental contaminants), which constitute a technological risk factor for the consumer. Residues of pesticides such as chlorpyrifos, cypermethrin, endosulfan, cyhalothrin and parathion-methyl) are a threat to public health. One way of their entry to the human food chain is through the contaminated milk and meat. Therefore, milk samples were collected from villages situated within the radius of 25-35 Km on four different localities (Jhang road, Aminpur road, Sitiana road, and Sheikhupura road) of Faisalabad from September, 2007 to February, 2008. The pesticides residues were investigated in cattle and goat meat during the months of July, 2009 to December, 2009 to ensure safety of the meat for human consumption. Meat was collected at one month interval from different regions of Faisalabad. Milk and Meat samples were processed for extraction using solid phase micro-extraction (SPME) and pesticides residues were determined by high performance liquid chromatography. The pesticides residues thus determined were compared with the MRLs and the values reported in literature to assess the real risk to the health of general public.
The result of our present findings revealed that the milk samples of goat (50%) were found to be more contaminated as compared to cow samples (46%). On the other hand, the month wise comparison of samples showed that the milk samples collected during the winter season were found to be more contaminated as compared to the other months. The species comparison revealed that only endosulfan residues were significantly different in milk samples of cow and goat. Overall, 20-25% milk samples of both species surpassed the MRL levels for different pesticides however; the residual level of endosulfan in all the milk samples of cow and goat did not exceed the MRL, while methyl parathion was not detected in any milk sample. These findings suggest creating awareness in dairy farmers regarding the avoidance of pesticide residues in milk. The residues of chlorpyrifos, cypermethrin, lambda-cyhalothrin and endosulfan in the meat of cattle and goat of present study are higher in concentration than the available MRL in the literature and the most reported values.
The meat samples of cattle from three sites in south-west are having slightly higher levels of residues of chlorpyrifos, cypermethrin, lambda-cyhalothrin and endosulfan than those collected from three sites in north-east of Faisalabad city. However, in case of goat meat this difference between north-east and south-west is non significant.
The residues of chlorpyrifos, cypermethrin, lambda-cyhalothrin and endosulfan in the meat of cattle and goat remained same in summer and in winter seasons. All the samples of muscles and organs of cattle and goat were not contaminated but a few samples were found to be contaminated with pesticides residues. About 13%, 25%, 4% and 2% muscle samples of cattle and goat were contaminated with chlorpyrifos, lambda-cyhalothrin, cypermethrin and endosulfan, respectively. Over all Chlorpyrifos, lambda-cyhalothrin, cypermethrin and endosulfan are about 34 times, 23 times, 47 times, and 27 times respectively, higher values than the MRL in positive meat samples.
The concentration of all pesticides residues found in the current study is alarming. The higher concentration of pesticides residues poses a potential threat to both livestock and human beings. Our data deserves a particular attention of regulatory authorities. All those products which surpass the permissible limits may be declared unhygienic due to their associated toxicological risks. Both the public and private sectors must cooperate in tackling the problem jointly.