PFAS Detected in 98.8% of Human Blood Samples

Per- and polyfluoroalkyl substances (PFAS) are a class of more than 15,000 synthetic chemicals that resist degradation in the environment and in the human body. A U.S. study published in the Journal of Occupational and Environmental Hygiene in April 2026 detected PFAS in 98.8% of 10,566 human blood samples.

PFAS and Chemical Classification

PFAS are fluorinated organic compounds used in industrial and consumer products. Their carbon-fluorine bonds give them high thermal stability and resistance to water, oil, and stains. PFHxS, or perfluorohexane sulfonic acid, is one PFAS compound used in textiles, furniture, and adhesives.

Blood Sample Findings

The study analysed serum and plasma samples from 10,566 people. Multiple PFAS types were found in 98.5% of the samples, and only 0.18% of samples contained a single PFAS chemical. The testing panels identified more than 70 unique PFAS combinations.

Health and Exposure Context

PFAS exposure occurs through contaminated water, food packaging, household products, and occupational contact. Previous research has linked certain PFAS with kidney cancer, testicular cancer, liver damage, immune system suppression, and reproductive and developmental harm.

Important Facts for Exams

• PFAS stands for per- and polyfluoroalkyl substances.
• PFAS are often called “forever chemicals” because they persist for long periods.
• PFHxS is one PFAS compound detected in 97.9% of the samples in the study.
• Serum and plasma are the two blood components used in many biomonitoring studies.

Biomonitoring and Mixture Assessment

Biomonitoring studies measure chemicals or their metabolites in human tissues and fluids. Chemical mixture assessment is used in toxicology when multiple substances may act through additive, synergistic, or antagonistic effects.