Unusual hepta‐ and octabrominated diphenyl ethers and nonabrominated diphenyl ether profile in California, USA, peregrine falcons (Falco peregrinus): More evidence for brominated diphenyl ether‐209 debromination

Abstract

High (maximum of 4.1 ppm lipid weight) levels of BDE‐209 and other higher brominated diphenyl ethers (BDEs) found in California, USA, peregrine falcon (Falco peregrinus) eggs (n = 95) provided an opportunity to examine homolog profiles of nona‐, octa‐, and hepta‐BDEs as possible evidence for biological debromination of BDE‐209. We found two congeners in eggs, an unidentified hepta‐BDE (BDE‐heptaUNK) and BDE‐202 (octa‐BDE) that are not present in commercial mixtures. In addition, BDE‐208 (nona‐BDE) was present at much higher (10‐fold) proportions in eggs than in commercial mixtures. To examine whether these unusual homolog patterns arose from assimilation of environmentally degraded BDE commercial mixtures, we compared nona‐hepta‐BDE homolog profiles of peregrine falcon eggs with those of weathered BDEs present in various abiotic matrices (sludge, sediment, and dusts). We found the profiles differed significantly: BDE‐207 was the major nona‐BDE in eggs, whereas BDE‐206 was the major nona‐BDE in abiotic matrices. Thus, the evidence for the biological debromination of BDE‐209 in peregrine falcons is twofold: Eggs have two congeners (BDE‐202 and −heptaUNK) that are not reported for any commercial mixtures nor in the abiotic matrices examined thus far, and eggs have higher‐brominated BDE homolog patterns that are different from those found in commercial mixtures or environmental matrices.