Persistent organochlorine pesticides and polychlorinated biphenyls in intensive agricultural soils from North India
B. Kumar, S. Kumar, R. Gaur, G. Goel, M. Mishra, S.K. Singh, D. Prakash, C.S. Sharmahttps://doi.org/10.17221/21/2011-SWRCitation:Kumar B., Kumar S., Gaur R., Goel G., Mishra M., Singh S.K., Prakash D., Sharma C.S. (2011): Persistent organochlorine pesticides and polychlorinated biphenyls in intensive agricultural soils from North India. Soil & Water Res., 6: 190-197.
Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were determined in agricultural soils from the northern states of India. The average concentration of OCPs was 37.67 ± 0.33 ng/g (dry weight − DW) while HCHs alone accounted for 93% followed by DDT (4.27%) and endosulphan (2.51%). The α/γ ratio of HCH (< 0.01–8.64) reflects the use of technical as well as lindane formulations. The ratio of p,p’-DDT/p,p’-DDE (0.16) and o,p’-DDT/p,p’-DDT (< 0.01) indicates the contamination of soils with the past use of technical DDT. The mean concentrations of endosulphan and dieldrin were 0.95 ± 0.53 ng/g (DW)and 0.16 ± 0.07 ng/g (DW), respectively. The average concentration of PCBs was 13.44 ± 0.06 ng/g (DW). The toxic equivalency (TEQ) calculated using WHO 2005-TEFs ranged from 0.01 to 105.40 pg WHO 2005-TEQ/g (DW) with the mean of 13.78 ± 0.11 pg WHO 2005-TEQ/g (DW). PCB-105 (25%), PCB-114 (18%), and PCB-118 (18%) were the dominant congeners and accounted for 61% while a non ortho PCBs contributed only 18% to total DL-PCBs. The contamination of soils is a matter of concern but is not alarming because the observed levels were lower than those given by the Canadian soil quality guidelines.Keywords:
accelerated solvent extraction (ASE); agricultural soil; organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs)