“An additional study has shown PFOA to be developmentally toxic, hepatotoxic, immunotoxic, and to have negative effects of thyroid hormone production.” – Wikipedia
“Hypothyroidism is the most common thyroid abnormality associated with PFAS exposure.[98] PFAS have been shown to decrease thyroid peroxidase, resulting in decreased production and activation of thyroid hormones in vivo.” – Wikipedia
“In general, people are exposed to PCBs overwhelmingly through food, much less so by breathing contaminated air, and least by skin contact.” – Wikipedia