PARENT SESSION

PM06 Emerging Pollutants
Exhibit Hall
8:00 AM - Monday

(PM057) Biomagnification of perfluorooctane sulfonate (PFOS) in an eastern Arctic food web.

Tomy, G¹, Budakowski, W², Halldorson, T¹, Helm, P³, Stern, G¹, Fisk, A⁴, Pepper, K⁵, Tittlemier, S⁵, ¹ Department of Fisheries and Oceans, Winnipeg, Manitoba, Canada² K'Prime Technologies, Winnipeg, Manitoba, Canada³ Ministry of Environment, Toronto, Ontario, Canada⁴ University of Georgia, Athens, Georgia, USA⁵ Health Canada, Ottawa, Ontario, Canada

ABSTRACT- An eastern Arctic marine food web was analyzed for PFOS [C₈F₁₇SO₃^-] and its neutral-precursors [PFOSA: C₈F₁₇SO₂NH₂ and N-EtPFOSA: C₈F₁₇SO₂NH(C₂H₅)] to examine the extent of their bioaccumulation. Stable isotopes of nitrogen (¹⁵N) were also used to estimate trophic levels (TLs) in the food web. PFOS was detected in all species analyzed and mean concentrations ranged from 0.28 +/- 0.09 ng/g (wet weight, whole body) in clams (Mya truncata) to 20.2 +/- 3.9 ng/g (wet weight, liver) in glaucous gull (Larus hyperboreus). N-EtPFOSA was detected in all species except redfish with mean concentrations ranging from 0.46 +/- 0.09 ng/g (wet weight) in mixed zooplankton to 77.1 +/- 67.4 ng/g (wet weight) in Arctic cod (Boreogadus saida). This is the first report of N-EtPFOSA in Arctic biota. PFOSA was only detected in livers of beluga (Delphinapterus leucas) (20.9 +/- 7.9 ng/g, wet weight) and narwhal (Monodon monoceros) (8.3 +/- 1.3 ng/g, wet weight), possibly indicating that N-EtPFOSA and other PFOSA-type precursors are likely present but are being biotransformed to PFOSA. A positive linear relationship was found between PFOS concentrations (wet wt) and TL, based on ¹⁵N values, (r² = 0.51, p<0.0001) resulting in a trophic magnification factor (TMF) of 3.1. TL-corrected biomagnification factor estimates (i.e., calculated using predator/prey relationships) for PFOS ranged from 0.4 and 9. Both results indicate that PFOS biomagnifies in the Arctic marine food web. However, transformation of N-EtPFOSA and PFOSA, and potential other perfluorinated compounds to PFOS, may contribute to PFOS levels in marine mammals and may inflate estimated biomagnification values.

Key words: biomagnification, Perfluorooctane sulfonate, food web, arctic