PH11 Bioaccumulation and Biotransformation of POPs
Exhibit Hall
8:00 AM - Thursday, 13 November 2003
(PH111) Persistent Organic Pollutants in the Antarctic Marine Food Web.
Chiuchiolo, A1, Cochran, M1, Dickhut, R1, Ducklow, H1, 1 College of William and Mary/Virginia Institute of Marine Science, Gloucester Point, VA, USA
ABSTRACT- In the Antarctic, phytoplankton and krill (Euphausia superba) are key species supporting the marine food web. For example, Adélie penguins feed predominantly on krill. Moreover, phytoplankton and krill are important not only in the water column, but in the highly productive annual pack ice that extends hundreds of miles from the continent. We hypothesize that POPs are taken up by phytoplankton and sea ice microbial communities (SIMCO) following atmospheric deposition in the Antarctic. Thus, both ice algae and phytoplankton likely play a role in providing the first step in pollutant transport up the food chain. In this study, SIMCO, phytoplankton, and krill (juvenile and adult) were collected from the region west of the Antarctic Peninsula during the late winter and summer seasons. Samples from a dead Adélie penguin were also collected. The samples were analyzed for concentrations of various POPs and results indicate that levels of brominated diphenyl ethers (
BDE and in many cases individual BDE congeners) currently exceed levels of organochlorine pesticides (HCB, HCHs, heptachlor, heptachor epoxide and DDT) in Antarctic phytoplankton and krill. Moreover, POPs appear to concentrate in ice algae (SIMCO) in the winter compared with summer phytoplankton. This may be due to a combination of lower atmospheric deposition fluxes in summer versus winter, as well as an increased biomass of phytoplankton leading to biomass dilution of POPs in summer. The high levels of POPs in ice algae are reflected in the juvenile krill (collected from below the ice) that feed on the SIMCO during the winter, whereas adult krill have significantly lower levels of BDEs compared to phytoplankton.
Key words: antarctic, persistent organic pollutants, food web