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Title: Polychlorinated biphenyls and organochlorine pesticides in eels from Welsh Rivers
Author: N.S. Weatherley
Author: G.L. Davies
Author: D.S. Ellery
Document Type: Monograph
Organochlorine pesticides, including DDT and dieldrin, were widely introduced into agriculture in the 1950s. At about the same time, production of synthetic polychlorinated biphenyls (PCBs) was increasing for a variety of industrial applications. The high chemical stability and electrical resistance of PCBs led to their extensive use. Closed uses include transformers, capacitors, heat transfer and vacuum pump fluids. Open uses include fire retardants, plasticizers, lubricating and cutting oils. The same properties make PCBs extremely persistent in the environment and they have been detected since the early 1970s in most materials and locations, including remote polar regions. The input of PCBs to the UK environment peaked in the 1960s, but concern over effects on marine mammals, birds and humans led to global ban on production in the late 1970s (Harrad et al. 1994; Tanabe, 1988). DDT and dieldrin were also banned in the UK in the late 1980s for their toxicity and bioaccumulative properties. In Wales, PCBs were produced at the Monsanto plant near Newport until 1977. Elevated concentrations have been found in sediments around the plant discharge to the Severn Estuary (Davies an Robinson, 1994). Other localized cases of contamination have been reported in relation to uncontrolled sources such as contaminated land leachate (see Discussion). The profile of PCBs as contaminants of the UK freshwater environment has been reused recently by studies of concentrations in otter spraints (Mason 1989; Mason an Macdonald 1993a, 1993b, 1993c). Mason proposed that dietary sources of PCBs and organochlorine pesticides in fish were a significant constraint on otter populations in several major river catchments. This concern triggered recent surveys in North West and Northumbria Yorkshire NRA Regions (EERC, 1993a, 1993b).
Publisher: National Rivers Authority
Publication Date: 1995
Publication Place: Cardiff
Subject Keywords: Organochlorine compoundsPesticidesWater pollutionFishesBioaccumulationFood chainsAquatic mammalsRiversNational Rivers Authority
Geographic Keywords: Wales
Taxonomic Keywords: AnguilliformesLutra lutra
Extent: 49
Total file downloads: 296

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