Persistent organochlorine pesticide residues in freshwater systems and sediments from the Eastern Cape, South Africa

Abstract

Persistent organochlorines such as ΣDDT, chlordane, hexachlorobenzene (HCB), heptachlor and endosulfan were determined in water and sediment samples of freshwater systems in the Eastern Cape Province of South Africa that receive runoff from agricultural lands and effluents from industries. The organochlorine pesticides (OCPs) in water and sediments were determined by liquid/liquid extraction and Soxhlet extraction methods, respectively. Percentage recoveries ranged from 71.03 ± 8.15% (dieldrin) to 101.25 ± 2.17% (α-BHC) in water and from 88.22 ± 7.85% (endrin) to 109.63 ± 5.10 (β-BHC) in sediment. Th OCP levels ranged from trace (2,4′-DDD) to 450 ± 0.0002 ng/l (β-BHc) in water samples and from trace (aldrin and 2,4′-DDD) to 184 × 10 3 ± 0.7 ng/kg (β-BHC) in sediments for triplicate analyses. Some endocrine-disrupting OCPs such as 2,4′-DDT, 4,4′-DDT, 2,4′-DDE, heptachlor, endosulfan and the chlordanes were detected.