Environ Toxicol Chem. 2022 Jun 13. doi: 10.1002/etc.5396. Online ahead of print.
ABSTRACT
Polycyclic aromatic hydrocarbons (PAHs) are structurally diverse organic chemicals that can have adverse effects on the health of fishes through activation of the aryl hydrocarbon receptor 2 (AhR2). PAHs are ubiquitous in the environment, but alkyl PAHs are more abundant in some environmental matrices. However, relatively little is known regarding the effects of alkylation on the toxicity of PAHs to fishes in vivo and how this relates to potency for activation of the AhR2 in vitro. Therefore, objectives of this study were to determine the toxicity of benz[a]anthracene (BAA) and three alkylated homologues representing various alkylation positions to early life-stages of zebrafish (Danio rerio), and to assess the potency of each for activation of the zebrafish AhR2 in a standardized in vitro AhR transactivation assay. Exposure of embryos to each of the PAHs caused a dose-dependent increase in mortality and malformations characteristic of AhR2 activation. Each alkyl homolog had in vivo toxicities and in vitro AhR2 activation potencies different than the parent PAH in a position-dependant manner. However, there was no statistically significant linear relationship between responses measured in these assays. Results suggest a need for further investigation into the effect of alkylation on the toxicity of PAHs to fishes and greater consideration of the contribution of alkylated homologues in ecological risk assessments. This article is protected by copyright. All rights reserved.© 2022 SETAC.
PMID:35694968 | DOI:10.1002/etc.5396
