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Title: Results of the NRA Welsh regional marine bioaccumulation programme 1991-1995 : SE/EAU/95/9
Author: Gillian Davies
Author: Stephen Ellery
Document Type: Monograph
A marine'bioaccumulation study at 30 sites around the Welsh coastline with Fucus vesiculosus, Mytilus edulis and Cerastoderma edule as the target species, for a suite of determinands consisting of trace metals and organic compounds, commenced in 1993. Prior to that some bioaccumulation studies had been carried out, but at a limited number of sites mainly in South Wales (Swansea Bay and the Severn Estuary). Bioaccumulation is an useful addition to water quality monitoring, as substances that only exist in very low levels in the environment (such as trace metals and organic compounds), can be detected in tissue. Results have to be interpreted very cautiously however, to put them into context, as there are no Environmental Quality Standards for bioaccumulation. Higher levels (compared to the rest of the Welsh Coastline) of Copper, Zinc, Mercury, Lead and Nickel were found in each target organism associated with the industrial embayments, such as Swansea Bay and within the two major estuaries of Wales - the Dee and the Severn. In comparison with the earlier Welsh Water Authority Tidal Waters Bioaccumulation Programme 1978/1979 data (Welsh Water Authority, 1982; Appendix V), the spatial variations found in this report are very similar and can be linked mainly to anthropogenic inputs from the heavy industries, such as metal refining and coal-mining. 'Natural' inputs, associated with old metalliferous mining areas and discharged via rivers draining these areas, are also a factor and give rise to localised elevations in otherwise clean areas e.g. the levels of lead in Mytilus edulis at Castlerocks, Aberystwyth, which is affected by the Ystwyth and Rheidol catchments that drain old metalliferous mining areas.
Publisher: National Rivers Authority
Publication Date: 1995
Publication Place: Cardiff
Subject Keywords: Coastal watersWater quality surveysBioaccumulationTrace elementsMetalsOrganic compoundsIndustrial pollution
Geographic Keywords: Wales
Taxonomic Keywords: Fucus vesiculosusMytilus edulisCerastoderma edule
Extent: 25; + appendices
Total file downloads: 48

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