Organochlorine pesticides in surface soils and sediments from obsolete pesticides dumping site near Lahore city, Pakistan: contamination status and their distribution

Abstract

Surface soil and sediment samples were collected from the surroundings of Lila stream, which passes through the obsolete pesticides dumping area Kalashah Kaku near Lahore city, to evaluate the residual levels of 19 organochlorine pesticides (OCPs), their distribution and potential sources. OCPs followed the order: ∑ DDT>∑ HCH>dicofol>endrin>heptachlor>dieldrin. Ratios of β to γ-HCH highlighted an old source of technical HCH in the study area, whereas the predominance of p, p′-DDT and p, p′-DDE indicated presence of technical DDT in surface soils. Factor analysis based on principal component analysis identified the origin of OCPs from industrial activities in Kalashah Kaku and waste dumping from Ittehad Chemical Industries via open drains into Lila stream. Greater levels of DDTs and HCHs above quality guideline pose potential exposure risk to biological organisms, safety of agricultural products and human health in the surrounding of Lila stream.

Keywords:

• Lahore city
• Lila stream
• obsolete dumping site
• organochlorine pesticides (OCPs)

Acknowledgements

The authors acknowledge the assistance of Mr Mustjab and Mr Azhar in laboratory analyses and the Director Toxicology Laboratory NARC, Islamabad for providing necessary equipment facility for pesticide analyses. Research work was done when Mr Jabir Hussain was a MPhil student.