LAUSR

Polychlorinated biphenyls (PCBs) cause significant health and reproductive problems in many vertebrates. Exposure during embryogenesis likely leads to defects in organ development, compromising survival and growth through adulthood. This study identifies the impact of PCBs on the embryonic development of key organs and resulting consequences on survival and growth. Zebrafish embryos were treated with individual PCB congeners (126 or 104) or one of four Aroclor mixtures (1016, 1242, 1254, or 1260) and analyzed for changes in gross embryonic morphology. Specific organs were assessed during embryonic development for defects using a variety of transgenic zebrafish to improve organ visualization. Resulting larvae were grown to adulthood, while survival and growth were assayed. Embryonic gross development upon PCB treatment was abnormal with defects presenting in a concentration dependent manner in the liver, pancreas, heart, and blood vessel organization. PCB 126 treatment resulted in the most consistently severe and fatal phenotypes, while treatments with PCB 104 and Aroclors resulted in a range of more subtle organ defects. Survival of fish was highly variable, though the growth rates of surviving fish was relatively normal suggesting that maturing PCB-treated fish that survive develop compensatory strategies needed to reach adulthood. Lifespan analyses of fish from embryogenesis through adulthood, as in this study, are scarce but important for the field as they help identify foci for further studies. This article is protected by copyright. All rights reserved.