Home > Research > Publications & Outputs > Organochlorine pesticide residues in archived U...

Links

Text available via DOI:

View graph of relations

Organochlorine pesticide residues in archived UK soils.

Research output: Contribution to Journal/MagazineJournal articlepeer-review

Published
<mark>Journal publication date</mark>05/2001
<mark>Journal</mark>Environmental Science and Technology
Issue number10
Volume35
Number of pages7
Pages (from-to)1989-1995
Publication StatusPublished
<mark>Original language</mark>English

Abstract

Archived background soils (“Broadbalk', 1944−1986) and sludge-amended soils (“Luddington”, 1968−1990), collected from long-term agricultural experiments in the UK, were analyzed for a range of organochlorine (OC) pesticides to establish trends over time. Concentrations typically ranged from 0.1 to 10 ng/g of soil (dry weight), with γ-hexachlorocyclohexane (γ-HCH), dieldrin, and p,p‘-DDE consistently having the highest concentrations. The trends in the Broadbalk background soils are largely consistent with usage patterns, with peak concentrations occurring in the 1960s for DDTs and between the 1960s and the 1980s for the other OCs. In the Luddington control and sludge-amended soils, several of the OCs show a significant decline in concentrations from the late 1960s to 1990, with half-lives ranging from 7 years (α-HCH) to 25 years (dieldrin). The sludge-amended plot received 125 tonnes of sludge per ha in 1968, which was mixed in to a depth of 15 cm. It appears that the sludge treatment had little effect on concentrations in the soil, with no significant difference between control soil and sludge-amended soil for most compounds, except for HCB, p,p‘-DDE, and dieldrin. Enantiomeric fractions (EFs) of some chiral pesticides (α-HCH, cis- and trans-chlordane, and o,p‘-DDT) were determined in the Luddington soils. Results reveal that enantioselective degradation of OC pesticides is occurring in these soils for trans-chlordane (TC) and cis-chlordane (CC). However, the depletion over time is not statistically significant, and there is no statistically significant difference between EFs in the control soil and sludge-amended soil. This indicates that enantioselective microbial degradation was not consistent over time and that the addition of sludge to soil did not significantly alter the enantiomeric preference of the microbial community.