Impact of Persistent 'Forever Chemicals' on Developing Male Brain Discovered by Researchers

Recent research conducted by the Del Monte Institute for Neuroscience at the University of Rochester has revealed concerning effects of 'forever chemicals,' scientifically known as per- and polyfluoroalkyl substances (PFAS), on the developing male brain. These chemicals, which have been extensively used in consumer and industrial products for nearly a century, do not naturally degrade and persist in the environment, posing ongoing health risks.

Among these substances, perfluorohexanoic acid (PFHxA) is a shorter-chain PFAS compound often considered to be less harmful. However, the new study indicates that early life exposure to PFHxA can lead to subtle yet significant neurobehavioral changes in male mice. Specifically, these mice showed increased anxiety behaviors, reduced activity levels, and memory challenges, effects that persisted into adulthood. Importantly, these effects were not observed in female mice, highlighting a possible gender-based vulnerability.

The researchers administered PFHxA to pregnant and lactating mice via their diet, simulating exposure during critical periods of brain development. The findings suggest that in utero and early postnatal exposure to PFHxA may interfere with normal brain maturation, leading to long-term behavioral alterations. This is especially alarming given that low-chain PFAS such as PFHxA have been marketed as safer alternatives to traditional, longer-chain PFAS, which are now being phased out due to their toxicity.

"While these effects were mild, the fact that they appeared exclusively in males is reminiscent of the gender disparities seen in neurodevelopmental disorders like autism and ADHD," explained Dr. Ania Majewska, senior author of the study. The results add to growing evidence that male brains may be more susceptible to environmental toxins during critical periods of neurodevelopment.

The study also underscores the importance of further investigation into the neurotoxicity of PFHxA and similar chemicals. Despite its shorter molecular length, PFHxA remains environmentally persistent and was restricted by the European Union in 2024. The Environmental Protection Agency (EPA) also established its first national drinking water standard for PFAS in 2024, aiming to reduce human exposure.

This research emphasizes the need for comprehensive evaluation of short-chain PFAS, which are often perceived as safer but may carry unforeseen neurodevelopmental risks. As environmental and health agencies consider regulations, understanding the long-term impacts of these chemicals on brain development becomes critical.

The findings, published in the European Journal of Neuroscience, urge policymakers and scientists to prioritize studies on the cellular and molecular mechanisms of PFHxA's neurotoxicity, especially in brain regions related to motor control, emotion, and memory. Protecting vulnerable populations, including fetuses and children, from exposure to these chemicals is paramount for safeguarding future neurodevelopmental health.

For more details, see the study: Elizabeth C. Plunk et al, 'Gestational and Lactational Exposure to Perfluorohexanoic Acid Affects Behavior in Adult Male Mice: A Preliminary Study,' European Journal of Neuroscience, 2025. [doi:10.1111/ejn.70174]

Source: https://medicalxpress.com/news/2025-07-chemicals-impact-male-brain.html