Miljøgifter i store norske innsjøer, 2014

Abstract

Vi rapporterer her om forekomsten av miljøgifter i de pelagiske næringskjedene i innsjøene Mjøsa, Randsfjorden og Femunden, samt i supplerende materiale av fisk fra Tyrifjorden og Vansjø, innsamlet i 2014. Kvikksølv og organiske miljøgifter (cVMS, PCB, PBDE, PFAS, S/MCCP) ble analysert i prøver av fisk fra alle sjøene, samt i zooplankton i Mjøsa og Randsfjorden. Av hovedfunnene nevnes at siloksanforbindelsen D5 viser trofisk magnifisering i Mjøsa og Randsfjorden, samt at PFTrA er den dominerende PFAS-forbindelsen i leverprøver av fisk. We report here on the presence of contaminants in the pelagic food chains in the lakes Mjøsa, Randsfjorden and Femunden and in supplementary material of fish from Tyrifjorden and Vansjø, sampled in 2014. Mercury and persistent organic pollutants (cVMS, PCBs, PBDEs, PFAS, S/MCCP) were analyzed in samples of fish from all lakes, as well as zooplankton in Mjøsa and Randsfjorden. Among the key findings are that the siloxane D5 shows trophic magnification in Mjøsa and Randsfjorden and that PFTrA is the dominating PFAS in liver samples of fish.

The Norwegian Institute for Water Research (NIVA) and the Norwegian Institute for Air Research (NILU) are monitoring the occurrence of contaminants in the pelagic food webs in the lakes Mjøsa, Randsfjorden and Femunden, Southeast Norway, on behalf of the Norwegian Environment Agency. These large fjord lakes are respectively moderately, slightly and insignificantly impacted of discharges from local population, industry and agriculture. Supplementary samples of fish were obtained from Lake Tyrifjorden and Lake Vansjø. This monitoring program runs over four years, and started in 2013. Here we report the 2014 data, with focus on the occurrence of pollutants at different trophic levels and evaluation of their potential for biomagnification. ...