Thompson, A; Allen, JR; Dodoo, D; Hunter, J; Hawkins, SJ; Wolff, GA
The occurrence of chlorinated biphenyls (CBs) is well documented in diverse areas worldwide (e.g. Allan, 1990; Knap, 1990) and it is now established that these micropollutants have pronounced adverse effects on the health of marine biota (Reijnders, 1986; Tanabe, 1988). There are, however, few recent published reports on their background levels, occurrence and distributions in waters and sediments of the UK. Furthermore, many of the reports which exist are concerned with the North Sea (e.g. Klamer & Fomsgaad, 1993), whilst there are virtually no published reports of background contamination in the Irish Sea. Recently, a detailed study of Liverpool Bay in the Irish Sea (Camacho-Ibar, 1991; Camacho-Ibar & McEvoy, submitted) has shown that there is considerable contamination by CBs. This is thought to derive primarily from the sewage sludge dumping (Fig. l(A)), as well as from local riverine inputs via the Dee and Mersey Estuaries (see also Law et al., 1991).
In view of the paucity of data, a study was undertaken of the levels of 21 CB congeners (IUPAC Nos: trichlorobiphenyls 18, 28, 31; tetrachlorobiphenyls 44, 47, 49, 52, 66; pentachlorobiphenyls 101, 105, 118; hexachlorobiphenyls 128, 138, 141, 151, 153, 156; heptachlorobiphenyls 170, 180, 183; octachlorobiphenyl 194) in the common mussel, Mytilus edulis (Farrington et al., 1983), from Irish and North Sea waters. Sediment samples from eight sites in the Irish Sea basin were also analysed.