Sources of PCBs to Maryland Fish

Abstract

Polychlorinated biphenyl congeners were measured in 520 composite fish tissue samples collected from Maryland between 1999 and 2004. Thirty-six species were sampled from 190 sites. PCB concentrations in fish tissues were compared across taxa, regions and to Maryland fish consumption advisory levels. A multivariate analysis of PCB congeners in 126 white perch and 94 channel catfish from diverse locations was used to investigate patterns of PCB transport. The greatest PCB concentrations were measured in channel catfish from the Patapsco (1770 ng/g wet) and Potomac Rivers (1770 ng/g wet), the northern Chesapeake Bay (1000 ng/g wet), the Chesapeake and Delaware Canal (850 ng/g wet), and in carp from Back River (1400 ng/g wet). PCB congener patterns varied spatially and reflected local PCB sources. Congener signatures were used to map the contamination associated with each PCB source region. Apparent congener transport distances correlated positively with hydrophobicity and negatively with volatility.