High PFOS Levels Linked to Higher Kidney Cancer Odds in Okinawa Study

Participants in an Okinawan case-control study who carried the highest measured serum concentrations of perfluorooctane sulfonate, or PFOS, had roughly eleven times the odds of renal cell carcinoma compared with those in the lowest exposure category, according to research published in Environmental Science and Pollution Research in 2026. The association remained significant whether or not the statistical models adjusted for a measure of kidney function.

The study addresses a question the authors describe as still open. An association between exposure to per- and polyfluoroalkyl substances (PFAS) and renal cell carcinoma has been suggested, but epidemiological evidence remains limited. Okinawa offered a setting for the research because firefighting foam from military airbases has left the local population potentially highly exposed to PFAS.

The researchers enrolled patients with pathologically confirmed primary renal cell carcinoma together with control participants. They measured PFAS concentrations in serum and grouped exposure levels into tertiles, from lowest to highest. Multivariable logistic regression models were then used to estimate odds ratios and 95 percent confidence intervals for the disease.

The central result concerned PFOS. Participants in the highest PFOS tertile had significantly higher odds of renal cell carcinoma than those in the lowest tertile. In models that included adjustment for estimated glomerular filtration rate, the odds ratio was 11.3 with a 95 percent confidence interval of 3.52 to 41.6. In models fitted without eGFR, the odds ratio was 10.83 with a confidence interval of 3.46 to 38.57.

The authors fitted the models both ways to evaluate potential overadjustment, since adjusting for a variable could theoretically mask an association. The consistency of the PFOS result across both specifications indicates the finding does not depend on how kidney function was treated in the analysis.

The results for other PFAS compounds differed. Perfluorooctanoic acid (PFOA) and perfluorohexane sulfonate (PFHxS) showed inverse associations with renal cell carcinoma in the same study population, meaning higher measured concentrations were linked to lower odds of the disease.

Mixture analyses, which are designed to estimate the combined effect of multiple PFAS chemicals simultaneously, produced inconsistent results across methods. Quantile g-computation, one such approach, found no overall mixture effect, yielding an odds ratio of 0.96 with a 95 percent confidence interval of 0.77 to 1.19.

The authors present their findings as epidemiological evidence supporting a potential link between PFOS exposure and renal cell carcinoma, while emphasizing that the study does not establish causality. They underscore the need for prospective studies that follow participants over time to clarify the relationship between PFAS exposure and kidney cancer.

The study’s scope is defined by its design and setting: a case-control comparison within a potentially highly PFAS-exposed Okinawan population, with exposure measured in serum. Within that scope, the markedly elevated odds associated with high PFOS concentrations, and their persistence across both model specifications, mark the result as one that prospective research will need to examine further.

Subject of Research: Association between serum PFAS concentrations, particularly PFOS, and the odds of renal cell carcinoma in an Okinawan case-control study.

Article Title: Exposure to per- and polyfluoroalkyl substances and the odds of renal cell carcinoma: a case-control study

Article References: Ando, S., Harada, K. H., Oshiro, Y., Goya, M., Lyu, Z., Harada Sassa, M., & Tokuda, Y. (2026). Exposure to per- and polyfluoroalkyl substances and the odds of renal cell carcinoma: a case-control study. Environmental Science and Pollution Research. https://doi.org/10.1007/s11356-026-38327-1

Image Credits: AI Generated

DOI: 10.1007/s11356-026-38327-1

Keywords: PFAS, PFOS, renal cell carcinoma, kidney cancer, case-control study, Okinawa, environmental epidemiology, logistic regression, Japan, Environmental Science and Pollution Research, Exposure, per-