White blood cell. Credit: NCI
Key points:
- A new study shows PFAS chemicals can interfere with white blood cells.
- A chemical developed to replace legacy PFAS due to toxicity has been found to suppress the immune-saving abilities of white blood cells.
- Further testing needs to be done in terms of toxicity limits and exposure over time.
Researchers at NC State have found another toxic consequence of forever chemicals. In a new study, the team has shown per- and polyfluoroalkyl substances (PFAS) can suppress the neutrophil respiratory burst—the method white blood cells, or neutrophils, use to kill invading pathogens.
Published in the Journal of immunotoxicology, the study focuses on the two branches of the human immune system: adaptive and innate.
“It’s pretty well-established that PFAS are toxic to the adaptive immune system, but there hasn’t been as much research done on their effects on the innate immune system,” said Drake Phelps, a former Ph.D. student at North Carolina State University and first author of the study.
The research team examined the effect of nine environmentally relevant legacies and emerging PFAS on neutrophils from zebrafish embryos, neutrophil-like cells, and human neutrophil cells cultured from donor blood. The PFAS included in the study were all detected in the Cape Fear River and the blood serum of residents whose drinking water came from the Cape Fear River.
Of the nine PFAS tested, only GenX suppressed the neutrophil respiratory burst in embryonic zebrafish, neutrophil-like cells, and human neutrophils. PFHxA also suppressed the respiratory burst, but only in embryonic zebrafish and neutrophil-like cells. GenX is an emerging PFAS developed to replace older, legacy PFAS that have proven toxic.
The researchers note that while they had interesting findings, more research needs to be done to meet the gaps in the study. Most noteably, samples in the study were only exposed to the chemicals for four days, and thus can not be compared to real human exposure over the course of four decades or more.
“This paper isn’t the end of the road—it’s the first step. Hopefully our work may help prioritize further study of these two chemicals,” said Jeff Yoder, professor of comparative immunology at NC State and corresponding author of the study.