A Systematic Review of Polycyclic Aromatic Hydrocarbon Derivatives: Occurrences, Levels, Biotransformation, Exposure Biomarkers, and Toxicity

Abstract

Polycyclic aromatic hydrocarbon (PAH) derivatives constitute a significant class of emerging contaminants that have been ubiquitously detected in diverse environmental matrixes, with some even exhibiting higher toxicities than their corresponding parent PAHs. To date, compared with parent PAHs, fewer systematic summaries and reanalyses are available for PAH derivatives with great environmental concerns. This review summarizes the current knowledge on the chemical species, levels, biotransformation patterns, chemical analytical methods, internal exposure routes with representative biomarkers, and toxicity of PAH derivatives, primarily focusing on nitrated PAHs (NPAHs), oxygenated PAHs (OPAHs), halogenated PAHs (XPAHs), and alkylated PAHs (APAHs). A collection of 188 compounds from four categories, 44 NPAHs, 36 OPAHs, 56 APAHs, and 52 XPAHs, has been compiled from 114 studies that documented the environmental presence of PAH derivatives. These compounds exhibited weighted average air concentrations that varied from a lower limit of 0.019 pg/m3 to a higher threshold of 4060 pg/m3. Different analytical methods utilizing comprehensive two-dimensional gas chromatography coupled with high-resolution time-of-flight mass spectrometry (GC × GC-TOF-MS), gas chromatography coupled to time-of-flight mass spectrometry (GC-TOF-MS), comprehensive two-dimensional gas chromatography coupled to quadrupole mass spectrometry (GC × GC-QQQ-MS), and Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS), that adopted untargeted strategies for the identification of PAH derivatives are also reviewed here. Additionally, an in-depth analysis of biotransformation patterns for each category is provided, including the likelihood of specific biotransformation reaction types. For the toxicity, we primarily summarized key metabolic activation pathways, which could result in the formation of reactive metabolites capable of covalently bonding with DNA and tissue proteins, and potential health outcomes such as carcinogenicity and genotoxicity, oxidative stress, inflammation and immunotoxicity, and developmental toxicity that might be mediated by the aryl hydrocarbon receptor (AhR). Finally, we pinpoint research challenges and emphasize the need for further studies on identifying PAH derivatives, tracking external exposure levels, evaluating internal exposure levels and associated toxicity, clarifying exposure routes, and considering mixture exposure effects. This review aims to provide a broad understanding of PAH derivatives’ identification, environmental occurrence, human exposure, biotransformation, and toxicity, offering a valuable reference for guiding future research in this underexplored area.

Distribution and Risk Assessment of 80 Polycyclic Aromatic Compounds in Surface Water and Industrial Effluent in the Upper Yangtze River, China

“…It should be noted that the risks of some PACs were not assessed because toxicity data were not available. Previous study reported that some SPAHs, such as 5-methylchryren, 7,12-benz­[ a ]­anthracenquinone 1,8-dinitropyrene, and 7-chlorobenz­[ a ]­anthracene, were much more mutagenic and carcinogenic than those of parent PAHs. − Toxicities of these PACs should be further investigated for filling the knowledge and data gap and improving the risk management of PACs.…”

Identification and Prioritization of Organic Pollutants in Human Milk from the Yangtze River Delta, China

“…Humans are exposed to PAHs and their derivatives mainly through diet, inhalation, and dermal contact, and PAH derivatives are usually 10 to 1000 times more carcinogenic than the parent PAHs. 31,32 Some esters were also identified, and >30% of these esters were phthalates (PAEs). PAEs are endocrine disruptors and can also cause neurodevelopmental problems and hepatic toxicity.…”

COMPAS-3: a Data Set of peri-Condensed Polybenzenoid Hydrocarbons

“…Because they contain only benzene-the prototypical aromatic system-PBHs are sometimes considered the prototypical PASs and serve as model systems for investigating chemical concepts such as aromaticity 1 and reactivity. 2 In addition to their importance for fundamental studies, PBHs are pervasive in both the natural and man-made environments, and play key roles in multiple areas of research, including the formation of stars, 3-6 human health, 7 environmental impact, 8 andmore recently-as promising materials for organic electronics. 9 PASs in general, and PBHs in particular, have been used for a variety of electronic and optoelectronic technologies, including field effect transistors, [10][11][12][13][14] solar cells, 15 chemical sensors, 16 anode and cathode materials, [17][18][19][20][21] and anolytes 22 for redox-flow batteries.…”