R8 AM Contamination Source Identification and Apportionment
Thursday, 17 November 2005: 8:00 AM - 11:40 AM in 331-332

(TEU-1117-748054) Identification of Bioaccumulated Halogenated Natural Products.

Teuten, E¹, Reddy, C¹, ¹ Woods Hole Oceanographic Institution, Woods Hole, MA, USA

ABSTRACT- Over the last decade, at least 20 halogenated organic compounds (HOCs) of unknown origin have been observed bioaccumulated in animal tissues. Determining whether these compounds are industrially or naturally-derived is of great importance. If they are industrially synthesized, their source must be determined, whereas if they are produced naturally they could provide insight on the cycling and environmental fate of industrial HOCs. To address the origin of these compounds, we have analyzed their natural abundance radiocarbon content. Radiocarbon analysis provides a very effective means of distinguishing industrial HOCs, which are generally derived from petrochemicals and contain no radiocarbon, from the contemporary ¹⁴C content of natural HOCs. We have shown that two methoxylated polybrominated diphenyl ethers (MeO-PBDEs) found in a True's beaked whale are natural products and not metabolites of industrial PBDEs, which are used as flame retardants. Following analysis of the blubber from a selection of marine mammals from coastal New England, we have identified several previously unreported mixed halogenated bipyrroles. Four other similar bipyrroles have been found previously in animal tissue. It has been assumed that these compounds are natural products, although no natural sources are known. Studies are underway to isolate these compounds for radiocarbon analysis, and determine whether they have a natural or industrial source.

Key words: bioaccumulation, halogenated, origin