Adult female rats perinatally exposed to perfluorohexane sulfonate (PFHxS) and a mixture of endocrine disruptors display increased body/fat weights without a transcriptional footprint in fat cells

Perfluorohexane sulfonate exposure caused multiple developmental abnormalities in early life of zebrafish

Perfluorohexane sulfonate (PFHxS) has been listed as a new persistent organic pollutant since 2022. Although the production and use of PFHxS are now restricted, it remains highly persistent in aquatic environments for decades. However, so far research about the toxic effects on early-life exposure of PFHxS and underlying mechanisms are still limited. In this study, we employed both wild type and specifically labeled transgenic zebrafish as model to investigate the developmental toxicity of PFHxS during early-stage exposure in zebrafish. A series of phenotypic and molecular indicators were analyzed at various time points between 24 h post-fertilization (hpf) and 7 days post-fertilization (dpf). Our data showed that the acute toxicity of PFHxS was much lower than PFOS, with a lethal concentration 50% of 508.11 ± 88.54 μM at 120 hpf. Low-dose PFHxS exposure significantly altered heart rates, blood flow, and swimming behavior in zebrafish larvae, suggesting potential cardiotoxicity and neurotoxicity of zebrafish. Data from transgenic zebrafish with specifically labeled hearts (CZ40) confirmed that PFHxS affects cardiovascular system development. PFHxS-induced changes in transgenic zebrafish with labeled liver and pancreas (CZ16) suggest that PFHxS may cause metabolic disorders and contribute to developmental defects. Gene expression analysis showed that PFHxS with potential estrogenic effect might also affect the gonadal development of zebrafish. Our study can offer an insight into the toxicity of PFHxS in aquatic environment and health risks of early-stage PFHxS exposure in humans.

Association Between Prenatal Exposure to Per- and Poly-Fluoroalkyl Substances From Electronic Waste Disassembly Areas and Steroid Hormones in Human Milk Samples

Per- and poly-fluoroalkyl substances (PFAS), which are long-lasting environmental contaminants that are released into the environment during the e-waste disassembly process, pose a threat to human health. Human milk is a complex and dynamic mixture of endogenous and exogenous substances, including steroid hormones and PFAS. Therefore, in this study, we aimed to investigate the association between PFAS and steroid hormones in human milk from women living close to an e-waste disassembly area. In 2021, we collected milk samples from 150 mothers within 4 weeks of delivery and analyzed them via liquid chromatography-tandem mass spectrometry to determine the levels of 21 perfluorinated compounds and five steroid hormones (estrone, estriol, testosterone, progesterone, and androstenedione [A-dione]). We also performed multiple linear regression analysis to clarify the association between maternal PFAS exposure and steroid hormone concentrations. Our results indicated that PFOA and PFOS were positively associated with estrone (β, 0.23; 95% CI, 0.08-0.39) and A-dione (β, 0.186; 95% CI, 0.016-0.357) concentrations in human milk, respectively. Further, the average estimated daily intake of PFOA and PFOS were 36.5 ng/kg bw/day (range, 0.52-291.7 ng/kg bw/day) and 5.21 ng/kg bw/day (range, 0.26-32.3 ng/kg bw/day), respectively. Of concern, the PFAS intake of breastfeeding infants in the study area was higher than the recommended threshold. These findings suggested that prenatal exposure to PFAS from the e-waste disassembly process can influence steroid hormones levels in human milk. Increased efforts to mitigate mother and infant exposure to environmental pollutants are also required.

Prediction of the Interactions of a Large Number of Per- and Poly-Fluoroalkyl Substances with Ten Nuclear Receptors

Per- and poly-fluoroalkyl substances (PFASs) are persistent, toxic chemicals that pose significant hazards to human health and the environment. Screening large numbers of chemicals for their ability to act as endocrine disruptors by modulating the activity of nuclear receptors (NRs) is challenging because of the time and cost of in vitro and in vivo experiments. For this reason, we need computational approaches to screen these chemicals and quickly prioritize them for further testing. Here, we utilized molecular modeling and machine-learning predictions to identify potential interactions between 4545 PFASs with ten different NRs. The results show that some PFASs can bind strongly to several receptors. Further, PFASs that bind to different receptors can have very different structures spread throughout the chemical space. Biological validation of these in silico findings should be a high priority.

Do perfluoroalkyl substances aggravate the occurrence of obesity-associated glucolipid metabolic disease?

BACKGROUND

Since 2016, more and more studies have been conducted to explore the combination of obesity and perfluoroalkyl substances (PFASs) exposure, and the results indicate that PFASs may be connected with the occurrence of obesity-associated glucolipid metabolic disease (GLMD).

OBJECTIVES

This article summarizes the epidemiological studies on PFASs and obesity-related GLMD, as well as relevant experimental evidence.

RESULTS

(i) Both obesity and PFASs exposure can cause disorder of glucose and lipid metabolism (GLM). (ii) Obesity is a pivotal factor in the high incidence of GLMD induce by PFASs. (iii) PFASs are aggravating the occurrence of obesity-associated GLMD [e.g., diabetes, cardiovascular disease (CVD), and liver disease].

CONCLUSION

The paper fills the gaps among environmental chemistry/epidemiology/toxicology area research. More importantly, PFASs should be taken into account to explain the high-prevalence of obesity-related GLMD.

FUTURE DIRECTION

Three research programs are proposed to explore the synergistic mechanism of PFASs and obesity. In addition, three suggestions are recommended to solve the harm of PFASs pollutants to human beings.