Organochlorine pesticides in fish from the southern Baltic Sea: Levels, bioaccumulation features and temporal trends during the 1995–2006 period

The levels of HCH isomers, HCB and ∑DDTs∑DDTs were determined in five species of Baltic fish collected during 1995–2006. Some downward time trends of HCH isomer, pp′-DDE and pp  ′-DDD concentrations in Baltic fish were observed; in contrast, HCB and DDT concentrations did not exhibit any obvious trend. Concentrations of ∑HCHs∑HCHs expressed on a lipid weight basis were very similar in all species studied. In contrast, concentrations of ∑DDTs∑DDTs varied in tested species. The most abundant HCH isomer was β-HCH and among DDT-related compounds, pp  ′-DDE prevailed. In our investigations the sampling sites were not a crucial factor for organochlorine pesticide concentrations and patterns observed in fish, but the occurrence of several inter-species differences in the bioaccumulation features of OC pesticides were observed. For cod there was a positive correlation between fish size (length) and ∑DDT∑DDT concentration. In herring, sprat and salmon samples, ∑DDT∑DDT concentrations were negatively correlated with fat content.