Determination of residues of chlorpyrifos, its oxygen analog, and 3,5,6-trichloro-2-pyridinol in tissues of cattle fed chlorpyrifos

Abstract

Cattle were fed chlorpyrifos daily for 30 days at levels of 3,10, 30, and 100 ppm. Muscle, liver, kidney, omental fat, renal fat, and subcutaneous fat were collected at the end of this period. In addition, omental fat was collected by biopsy at weekly intervals for 5 weeks following withdrawal of the highest level of 100 ppm chlorpyrifos. Residues of chlorpyrifos and its oxygen analogue were determined by thermionic or flame photometric gas chromatography. The 3,5,6-trichloro-2-pyridinol moiety as the trimethylsilyl derivative was determined by electron-capture gas chromatography. The procedures were used to quantitate chlorpyrifos and its oxygen analogue down to 0.01 ppm and 3,5,6-trichloro-2-pyridinol to 0.05 ppm. Residues of chlorpyrifos were mainly in the fat tissues and averaged 0.02 ppm (<0.01-0.05 ppm) with 3 ppm in the diet and 3.28 ppm (2.28-4.70 ppm) in fat of cattle fed 100 ppm. The 3,5,6trichloro-2-pyridinol was predominantly in the liver and kidney and averaged 0.20 ppm (0.16-0.23 ppm) in liver and 0.11 ppm (0.09-0.15 ppm) in kidney at 3 ppm; 2.41 ppm (2.16-2.61 ppm) in liver and 1.75 ppm (1.46-1.95 ppm) in kidney at the 100 ppm feeding level. No chlorpyrifos oxygen analogue was detected in any tissue at any feeding level.DURSBAN, trademark of The Dow Chemical Company

A preliminary assessment of consumer’s exposure to pesticide residues in fisheries products

“…Chlorpyrifos is one of the most widely used active ingredients for pest control in the world. Many studies have been conducted in examining critical aspects of chlorpyrifos products as they relate to health and safety (Dishburger et al, 1997;Johnson et al, 1998;Clegg and Gemert, 1999). There are no reports directly pertaining to the contamination of sanitary chemicals on fisheries products.…”

Chlorpyrifos: Ecotoxicological Risk Assessment for Birds and Mammals in Corn Agroecosystems

“…Chlorpyrifos oxon is extremely susceptible to hydrolysis and is rapidly degraded to TCP and diethylphosphate (ATSDR 1995). Chlorpyrifos oxon is insecticidal and potentially toxic to non-target organisms in the environment, but it has not been demonstrated to be a significant environmental hazard due to the very small quantities formed and its lability (Dishburger et al 1977;Drevenkar et al 1993;Ivey et al 1972;Smith et al 1966 …”

Assessment of the dietary transfer of pesticides to dairy milk and its effect on human health

“…McKellar et al (1976) reported 0.01 to 0.02 mg/L of chloropyrifos and metabolite residue of 3,5,6, trichloro-2-pyridinol (TCP) in milk and milk products of cows when fed on 30 mg/kg of chloropyrifos for 14 days. Dishburger et al (1977) noted that addition of 3 mg/kg of chloropyrifos in cattle diet for 30 days results into accumulation of chloropyrifos and metabolite residue of TCP was <0.01, 0.08, 0.23, and 0.015 mg/kg in muscle, fat, liver and kidney, respectively. MacLachlan and Bhula (2007) estimated the transfer of pesticide residue from diet to milk, hence the quality and quantity of milk is slowly deteriorating and indirectly drinking milk of low quality causes health risk to human beings.…”