Distribution and risk assessment of selected organochlorine pesticides in Kyzyl Kairat village from Kazakhstan

Abstract

Concentrations of selected organochlorine pesticides (OCPs), i.e., 4,4'-dichlorodiphenyltrichloroethane (p,p'-DDT), its metabolites (p,p'-DDE, p,p'-DDD), and hexachlorocyclohexanes (HCHs), have been determined in 100 soil samples collected from a contaminated site centered around a former storehouse in the Kyzyl Kairat village, Almaty region, Kazakhstan, which constitutes an exemplary case example. The OCPs were observed in all analyzed soil samples, with predominance of α-HCH, p,p'-DDD, p,p'-DDE, and p,p'-DDT. Total concentrations ranged from 1.38 to 11,100 μg kg(-1) with an average value of 1040 μg kg(-1) for DDT and its metabolites and 0.1 to 438 μg kg(-1) with an average value of 24 μg kg(-1) for HCHs. The observed concentrations of the OCPs were found to be in agreement with previous studies and are rationalized in terms of the possible degradation pathways of DDTs and HCHs. Spatial distribution patterns of OCPs are elucidated by contour maps. Observed concentrations of the OCPs were used to evaluate the cancer risk to humans via ingestion, dermal contact, and inhalation of soil particles. The cancer risk mainly occurs from ingestion, whereas dermal exposure contributes to a minor extent to the total cancer risk. The risk associated with inhalation was found to be negligible. The total cancer risk for the studied OCPs were found to be p,p'-DDT ˃ p,p'-DDE ˃ p,p'-DDD ˃ α-HCH ˃ β-HCH ˃ γ-HCH.

Occurrences of Organochlorine Pesticides along the Course of the Buffalo River in the Eastern Cape of South Africa and Its Health Implications

“…In summer, the non-detectable target compounds were γ-BHC, heptachlor, 4,4-DDE, and endrin aldehyde, which could possibly have been converted to α-BHC, heptachlor epoxide, DDD or methoxychlor, and endrin, respectively, under favorable environmental conditions such as lower pH values, temperatures, and redox reactions [ 61 , 62 ]. The high concentration of methoxychlor, an important raw material for the production of certain insecticides and herbicides, could be associated with its low conversion through photo-oxidation [ 61 , 63 , 64 ]. γ-BHC, dieldrin, and endosufan II were detected at very low concentrations in summer, suggesting possible degradation to α-BHC, Eldrin, and/or endosulfan suplhate, respectively, at MSN.…”

Health Risk Assessment for the Residential Area Adjacent to a Former Chemical Plant

“…However, potentially toxic elements (arsenic and heavy metals) were assessed the most often [ 9 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ]. Among organic compounds the studies often included polycyclic aromatic hydrocarbons (PAHs), [ 19 , 20 , 21 , 22 , 23 , 24 , 25 ], petroleum hydrocarbons [ 22 , 26 , 27 ] and pesticides [ 3 , 11 , 28 , 29 ].…”

Legacy and current pesticide residues in Syr Darya, Kazakhstan: Contamination status, seasonal variation and preliminary ecological risk assessment

“…HCH isomers and lindane were reportedly not manufactured in Kazakhstan, but likely included among imported pesticides and stockpiles. According to the Ministry of Agriculture, HCH was not used in the territory of Kazakhstan, however a recent study reported high concentrations of organochlorine pesticides, including residues of DDT and HCH, in soils around a former storage facility in eastern Kazakhstan (Sailaukhanuly et al, 2016). These results suggest at the very least that lindane has been used or accumulated in soils upstream.…”