Oxy-PAHs: occurrence in the environment and potential genotoxic/mutagenic risk assessment for human health

Abstract

Structurally modified polycyclic aromatic hydrocarbons (PAHs) such as nitrated PAHs (nitro-PAHs) and oxygenated PAHs (oxy-PAHs) can be incriminated in the total toxicity of polycyclic aromatic compounds (PACs) fraction in the environment. Compared to nitro-PAHs, oxy-PAHs have been poorly studied. Oxy-PAHs covers compounds with different moieties such as polycyclic aromatic ketones (PAKs) and polycyclic aromatic quinones (PAQs). In this review, we have compiled exhaustively all the data available on the sources, the fate, and the occurrence of oxy-PAHs focusing on the most ubiquitous ones in the environment, ie PAKs and PAQs. Data concerning their genotoxicity, mutagenicity and tumor promotion potential for humans are also provided based on the mode-of-action analysis framework. Mutagenicity results based on the limited number of oxy-PAHs tested, are unequivocal on the concern they represent. Their omission in mutagenic/carcinogenic risk has caused a dramatic underestimation of cancer risk. On the basis of environmental and genotoxicological data, we suggest prioritized 4 major oxy-PAHs molecules in ecotoxicological and toxicological studies, namely 6 H-benzo[cd]pyren-6-one (BPO), 7,12-benz[a]anthracenequinone (BAQ), 5,12-naphthacenequinone (NCQ) and 11 H-benzo[b]fluoren-11-one (B[b]FO). We also propose to develop biomarkers of exposure and/or risk for these compounds, for example by quantification of DNA adducts.

Keywords:

• Environmental chemical
• oxygenated polycyclic aromatic hydrocarbons
• cancer
• genotoxicity
• mutagenicity
• systematic review

Acknowledgements

Adeline Clergé is grateful to the French Ministry of Education and Research for her Ph.D. fellowship. The authors also appreciate the excellent suggestions made by the reviewer. Authors thank Dr. Carla Delépée for her profound insight into the linguistic part of present work and instructive discussion concerning the factual content.

Declaration of interest

The employment affiliation of the authors is as shown on the cover page. However, it should be recognized that each individual participated in the review process and preparation of this article as an independent professional and not as a representative of their employer. Dr Jérémie Le Goff is employed by ADn’Tox SAS, http://www.adntox.com/, a toxicology company dedicated to human and environmental health that brings new solutions for genotoxicity assessment, in relation with DNA adducts detection. The authors have sole responsibility for the writing and content of the article. Preparation of this review was conducted during the normal course of the authors’ employment without any external support.