PFAS and PCBs linked to higher odds of multiple sclerosis in Swedish study
Analysis of blood from about 1,800 people in the EIMS cohort found that high concentrations of PFOS and certain hydroxylated PCBs were associated with roughly double the odds of a recent MS diagnosis, though the study is observational and does not prove causation.
- Researchers measured 14 PFAS and three hydroxylated PCB metabolites in blood from about 1,800 Swedes, including roughly 900 recent MS cases and 900 controls.
- Highest concentrations of PFOS and two hydroxylated PCBs were associated with about twice the odds of being diagnosed with MS compared with the lowest concentrations.
- An increase in total chemical mixture exposure was linked to higher odds of MS even after adjusting for known lifestyle and genetic risk factors.
- A genetic variant normally associated with reduced MS risk showed an unexpected increase in MS odds with higher PFOS exposure, suggesting a gene environment interaction.
- The study is observational and reports associations, so it cannot establish that these chemicals cause MS.
- Findings are published in Environment International (2026) and are based on the nationwide EIMS cohort.