Pollution‐induced tolerance to copper of nematode communities in the severely contaminated restronguet creek and adjacent estuaries, Cornwall, United Kingdom

Abstract

Pollution-induced community tolerance (PICT) has been proposed as an indicator of the deleterious effects of pollutants on communities in the field. Nematode assemblages were sampled at 10 estuarine sites that ranged from uncontaminated to grossly contaminated with metals. Relative tolerance of these assemblages to Cu was quantified using acute toxicity tests. There were large differences between sites in tolerance to Cu, and copper tolerance was strongly correlated with severity of contamination. Enhanced Cu tolerance occurred at two sites where Cu concentration in sediment was around 180 µg/g but not at a third site, where Cu concentration was 214 µg/g. This implies a threshold of effects on these nematode communities at ~200 µg/g Cu. Comparison with studies of nematode community composition in these same estuaries indicates that PICT is at least as sensitive as the best available ecological monitoring methods. It is, however, faster to carry out and requires much less taxonomic expertise. The PICT appears to be a sensitive indicator of ecological effects of pollution and has considerable promise as a monitoring tool

Habitat Conditions and Correlations of Sediment Quality Triad Indicators in Delaware Bay

“…It has also been shown in numerous places that organisms can adapt, at a cost, to badly contaminated habitats (Klerks and Levinton, 1989;Martinez and Levinton, 1996;Millward and Grant, 2000;Nacci et al, 2002). The presence of what are considered to be sensitive species (e.g.…”

Oxidative stress responses in two populations of Laeonereis acuta (Polychaeta, Nereididae) after acute and chronic exposure to copper

“…However, when adaptation to chemicals is considered, some authors restrict the use of this term to include only genetically based changes. Millward and Grant (2000) proposed the pollution-induced community tolerance (PICT) index as an indicator of the deleterious effects caused by pollutants on natural communities. The rationale of this approach is to consider that four types of changes can occur in a chemically disturbed community: (1) sensitive individuals and species are eliminated; (2) a replacement of sensitive species by more tolerant species occurs;…”

“…The PICT index was used in experimental exposures to copper to quantify the median lethal time to death (LT50) in nematode communities sampled respectively from a reference and a heavily polluted areas (Millward & Grant, 2000). These authors found an enhanced copper tolerance in organisms sampled from sites with a threshold copper concentration of about 200 lg/g of sediment.…”

Current and Future Perspectives Using Biomarkers to Assess Pollution in Aquatic Ecosystems

“…PICT measurements have been conducted using copper in laboratory assays to quantify the median lethal time to death (LT50) in nematode communities sampled from a reference site and from heavily polluted areas (51). An enhanced copper tolerance at a threshold copper concentration of about 200 mg=g of sediment in the area where animals were collected was reported.…”