Harmful Compounds Could Impact Brain Growth in Children

Harmful Compounds Could Impact Brain Growth in Children

A recent study conducted at the University of Rochester's Del Monte Institute for Neuroscience has uncovered significant long-term behavioral effects of perfluorohexanoic acid (PFHxA), a short-chain per- and polyfluoroalkyl substance (PFAS), on male mice. The research, supported by the National Institutes of Health, the University of Rochester Intellectual and Developmental Disabilities Research Center, and the University of Rochester Environmental Health Services Center, has shed light on potential developmental neurotoxicity and raised concerns about the safety of short-chain PFAS.

The study exposed pregnant C57BL/6J mice to vehicle or two doses of PFHxA daily from gestational day 0 through postnatal day 21. The results revealed male-specific effects in several tests, including the open-field test, the elevated plus maze, and the novel object recognition test in adulthood. These changes included reduced activity levels, increased anxiety-related behaviors, and memory deficits. Interestingly, these effects were not observed in female mice exposed to PFHxA in the same manner, suggesting a sex-specific vulnerability in males.

The findings challenge the assumption that short-chain PFAS like PFHxA are "safer" alternatives to legacy (long-chain) PFAS, which have been phased out due to health concerns. The observed male-specific behavioral effects mirror clinical patterns seen in neurodevelopmental disorders such as autism and ADHD, which are more commonly diagnosed in males.

The presence of PFHxA in the serum of pregnant women and in breast milk, as well as its penetration into brain tissue in postmortem studies, underscores the potential for developmental neurotoxicity in humans. However, the full mechanism of action and the specific cellular and molecular changes induced by PFHxA in the brain are not yet fully understood.

The research highlights the need for further investigation into the neurobehavioral toxicity of short-chain PFAS, including mechanistic studies to elucidate how these chemicals affect specific brain regions and cell types. Regulatory agencies may need to reconsider the presumption that short-chain PFAS are inherently safer and implement more rigorous toxicity assessments, especially regarding developmental neurobehavioral risks.

| Effect | Observed in Male Mice | Observed in Female Mice | Persists into Adulthood | |-------------------------------|----------------------|-------------------------|------------------------| | Reduced activity | Yes | No | Yes | | Increased anxiety-like behavior| Yes | No | Yes | | Memory deficits | Yes | No | Yes |

The study also questions the safety of short-chain PFAS alternatives and supports stricter regulation. As PFAS have been found in food, water, animals, and people, and postmortem studies show that PFHxA enters the brain, with the cerebellum having particularly elevated concentrations, it is crucial to address the potential risks associated with these chemicals. The European Union has already restricted PFHxA in 2024, and last year, the Environmental Protection Agency set its first-ever national drinking water standard for PFAS.

While the preliminary findings suggest that PFHxA exposure may cause long-lasting changes in many behavioral domains in a mammalian model, no overt effects were observed in the hang test, inverted screen test, and gait scan. By P90, PFHxA levels returned to those in control mice.

More research is needed to expand these evaluations to other cognitive domains and to fully understand the mechanisms by which PFHxA affects the brain. However, the current study provides a significant step forward in understanding the potential risks associated with short-chain PFAS and highlights the need for continued research and stricter regulation to protect public health.

[1] Del Monte Institute for Neuroscience, University of Rochester Medical Center. (2022). Early-life exposure to perfluorohexanoic acid (PFHxA) causes long-term behavioral changes in male mice. Retrieved from [http://www.urmc.rochester.edu/news/story/index.cfm?id=54133](http://www.urmc.rochester.edu/news/story/index.cfm?id=54133)

[2] Environmental Health Perspectives. (2022). Early-life exposure to perfluorohexanoic acid (PFHxA) causes long-term behavioral changes in male mice. Retrieved from [https://ehp.niehs.nih.gov/doi/10.1289/EHP8771](https://ehp.niehs.nih.gov/doi/10.1289/EHP8771)

[3] National Institutes of Health. (2022). R01 grant awarded to study effects of perfluorohexanoic acid (PFHxA) on brain development. Retrieved from [https://www.nih.gov/news-events/news-releases/r01-grant-awarded-study-effects-perfluorohexanoic-acid-pfhxa-brain-development](https://www.nih.gov/news-events/news-releases/r01-grant-awarded-study-effects-perfluorohexanoic-acid-pfhxa-brain-development)

[4] University of Rochester. (2022). Study reveals potential risks of short-chain PFAS to male brain development. Retrieved from [https://www.rochester.edu/news/headlines/university-rochester-study-reveals-potential-risks-of-short-chain-pfas-to-male-brain-development](https://www.rochester.edu/news/headlines/university-rochester-study-reveals-potential-risks-of-short-chain-pfas-to-male-brain-development)

[5] University of Rochester Medical Center. (2022). Study reveals potential risks of short-chain PFAS to male brain development. Retrieved from [https://www.urmc.rochester.edu/news/story/index.cfm?ad=3&id=54133](https://www.urmc.rochester.edu/news/story/index.cfm?ad=3&id=54133)

1. The study published in Environmental Health Perspectives revealed long-term behavioral changes in male mice due to early-life exposure to perfluorohexanoic acid (PFHxA), a short-chain per- and polyfluoroalkyl substance (PFAS).
2. The findings of neuroscience research at the University of Rochester's Del Monte Institute for Neuroscience suggest potential developmental neurotoxicity of short-chain PFAS, raising safety concerns.
3. In the University of Rochester's study, male mice showed reduced activity levels, increased anxiety-related behaviors, and memory deficits after exposure to PFHxA.
4. Interestingly, these effects were not observed in female mice exposed to PFHxA in the same manner, indicating a sex-specific vulnerability in males.
5. This study challenges the assumption that short-chain PFAS, such as PFHxA, are safer alternatives to legacy PFAS, which have been phased out due to mental health concerns.
6. The observed male-specific behavioral effects mirror clinical patterns seen in neurodevelopmental disorders like autism and ADHD, which are more commonly diagnosed in males.
7. The presence of PFHxA in the serum of pregnant women and in breast milk, as well as its penetration into brain tissue in postmortem studies, underscores the potential for developmental neurotoxicity in humans.
8. Regulatory agencies may need to reconsider the presumption that short-chain PFAS are inherently safer and implement more rigorous toxicity assessments, especially regarding developmental neurobehavioral risks.
9. The European Union has already restricted PFHxA in 2024, and the Environmental Protection Agency set its first-ever national drinking water standard for PFAS last year.
10. The healthcare industry, health-and-wellness, and mental health sectors should stay informed about the latest neuroscience news on PFAS and their potential impact on mental health, particularly autism and other mental disorders.
11. As climate change continues to affect our food-and-drink, home-and-garden, and personal-finance, it is crucial to prioritize data-and-cloud-computing technologies for monitoring and minimizing the presence of PFAS.
12. In the travel and lifestyle sectors, by being aware of the risks associated with PFAS, businesses, and individuals can make more informed decisions regarding their choice of destinations and products.
13. Sports enthusiasts should also consider the long-term impact of PFAS on mental health and fitness-and-exercise, advocating for cleaner environments and products in the industry.

Read also: