Genotoxicity assessment of perfluoroalkyl substances on human sperm

Abstract

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are synthetic chemicals that have been used in industry and consumer products. Because the presence of PFAS has been identified in humans and the environment in the last decade, human exposure to PFAS is a current public health concern. It has been shown that some PFAS lead to adverse health effects in the male reproductive system. However, there is no information about probable genotoxic effects of these chemicals on sperm cells. This study aimed to investigate the possible genotoxic damage on human sperm cells exposed to certain major PFAS compounds that were selected considering their extensive usage, high persistence in the environment, and high bioaccumulation in humans. These PFAS are perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorohexanoic acid (PFHxA). The alkaline comet assay was used to detect the DNA damage to sperm. Sperm cells were treated with 0.1-1 mM of each PFAS at 32 C for 1 h to obtain optimal survival. As a result of the experiments, it was discovered that the exposure to PFOS, PFOA, PFNA, and PFHxA did not cause significant levels of cytotoxicity and did not cause damage to sperm DNA under these conditions. The results suggest that the exposure to these PFAS did not interfere with sperm DNA. Indirect toxicity mechanisms should be taken into account to assess the association between the PFAS exposure and male reproductive toxicity.

Hexafluoropropylene oxide dimer acid (GenX) exposure induces apoptosis in HepG2 cells

“…PFASs, such as PFOA and GenX, are compounds with carbon-fluorine bonds that are commonly used in the manufacturing industry (Prevedouros et al, 2006). However, the accumulation of PFASs in the body causes multiple toxicities, including immunotoxicity, genetic toxicity, neurotoxicity, and hepatotoxicity (DeWitt et al, 2019;Emerce and Çetin, 2018;Fletcher et al, 2019;Gaballah et al, 2020;Ojo et al, 2020;Shane et al, 2020;Sun et al, 2019;Wen et al, 2020). In this study, we used hepG2 cells to demonstrate that GenX induces apoptosis in liver cells.…”

Application of the Key Characteristics of Carcinogens to Per and Polyfluoroalkyl Substances

“…Prior reviews reported that PFAS are not directly mutagenic and suggested that the DNA damage observed in some assays is likely a secondary event resulting from oxidative damage [47]. Recent toxicological studies reported similar findings for legacy and long-chain PFAS as well as the replacement and short-chain PFAS, GenX and PFBS [4,48,59,60]. Additionally, 28 day toxicity studies published by the National Toxicology Program for the carboxylates, PFOA, PFHxA, PFNA and PFDA and the sulfonates, PFOS, PFHxS, and PFBS, found no indication of genotoxicity in vivo or in vitro [61,62].…”

Assessment of the Emerging Threat Posed by Perfluoroalkyl and Polyfluoroalkyl Substances to Male Reproduction in Humans

“…Similarly, Joensen et al reported equivalent results in their 2009 study with PFOA and PFOS (129), but these outcomes could not be reproduced in their later study published in 2013 (131), possibly due to lower levels of PFAS recorded in this later cohort (0.5% for PFOS), in which no participants were classified in the 'high exposure' category as per the criteria in the first study. Further studies also failed to find an association between PFAS and sperm quality (132,133,(135)(136)(137); thus precluding the establishment of causative links (133,136). Sperm motility has also been found to correlate both positively and negatively with PFOA exposure.…”