May 6, 2024
Perfluoroalkylated substances (PFASs), commonly known as "forever chemicals" in the media, are pollutants that do not break down in the environment. Their chemical structure includes fluorine atoms bonded to carbon, which makes them effective at repelling water. This property has led to their use in water-repellent clothing, stain-resistant carpets and furniture, and nonstick cookware.
However, the same chemical structure that makes PFASs useful also makes them a concern for human and animal health, as there are no natural biological processes to remove them from the body. Once ingested, they accumulate and become more concentrated at each level of the food chain. PFASs can also cross the placental barrier, raising concerns about potential harm to developing embryos and fetuses.
A Chinese research team conducted a systematic review of the medical literature to examine if there is a link between maternal exposure to PFASs and an increased risk of ADHD in children. They analyzed data from several studies:
- A meta-analysis of five studies involving 2,513 mother-child pairs found no increase in ADHD risk from exposure to PFOA (perfluorooctanoate) or PFOS (perfluorooctane sulfonate). The consistency across these studies was high, with little variation and no evidence of publication bias.
- Another meta-analysis of three studies with 995 mother-child pairs also showed no increase in ADHD risk from exposure to PFNA (perfluorononanoate) or PFHxS (perfluorohexane sulfonate), with similarly negligible variation between studies and no publication bias.
- In an analysis comparing the highest and lowest quartiles of maternal exposure, a slight increase in ADHD risk was observed with PFOA exposure, while a slight decrease was noted with PFOS exposure. Both findings were marginally significant and may be due to the small sample sizes.
The researchers concluded that more studies are needed to confirm these findings due to the limited evidence available.
Huojie Yao, Yingyin Fu, Xueqiong Weng, Zurui Zeng, Yuxuan Tan, Xiaomei Wu, Huixian Zeng, Zhiyu Yang, Yexin Li, Huanzhu Liang, Yingying Wu, Lin Wen, and Chunxia Jing, “The Association between Prenatal Per- and Polyfluoroalkyl Substances Exposure and Neurobehavioral Problems in Offspring: A Meta-Analysis,” International Journal of Environmental Research and Public Health (2023), 20, 1668, https://doi.org/10.3390/ijerph20031668.