Virginia Institute of Marine Science
Environmental Science & Technology
Persistent organic pollutants reach polar regions by long-range atmospheric transport and biomagnify through the food web accumulating in higher trophic level predators. We analyzed Adelie penguin (Pygoscelis adeliae) samples collected from 2004 to 2006 to evaluate current levels of Sigma DDT (p,p'-DDT + p,p'-DDE) in these birds, which are confined to Antarctica. Ratios of p,p'-DDT to p,p'-DDE in Adelie penguins have declined significantly since 1964 indicating current exposure to old rather than new sources of Sigma DDT. However, Sigma DDT has not declined in Adelie penguins from the Western Antarctic Peninsula for more than 30 years and the presence of p,p'-DDT in these birds indicates that there is a current source of DDT to the Antarctic marine food web. DDT has been banned or severely restricted since peak use in the 1970s, implicating glacier meltwater as a likely source for DDT contamination in coastal Antarctic seas. Our estimates indicate that 1-4 kg.y(-1) Sigma DDT are currently being released into coastal waters along the Western Antarctic Ice Sheet due to glacier ablation.
Penguins Pygoscelis-Adeliae; Breeding-Season; Organochlorine Pollutants; Temporal Trends; Seabird Eggs; Food-Web; Pesticides; Residues; Contamination; Metabolism
Geisz, HN; Dickhut, RM; Cochran, MA; Fraser, WR; and Ducklow, HW, Melting glaciers: A probable source of DDT to the Antarctic marine ecosystem (2008). Environmental Science & Technology, 42(11), 3958-3962.