A major genomic study led by NIH researchers has uncovered strong links between air pollution and lung cancer in people who have never smoked—especially women and individuals of Asian descent. The findings shed light on a growing global health disparity that has long been poorly understood.
“Up to 1 in 4 lung cancer cases worldwide arise in people who never smoked,” the study noted. Most of these cases are adenocarcinoma, and disproportionately affect Asian populations and women. Researchers sequenced tumors from 871 never-smokers across four continents and found that high exposure to fine-particle pollution—common in urban and industrial areas—was associated with mutations in the TP53 gene, which normally helps suppress tumors.
Dr. Ludmil Alexandrov explained, “Air pollution is strongly associated with the same types of DNA mutations we typically associate with smoking.” The study also found that pollution exposure led to shorter telomeres, a marker linked to cancer and aging, and a 3.9-fold increase in a mutational signature usually seen in smokers.
Secondhand smoke showed only a slight increase in total mutations, but also contributed to telomere shortening. Dr. Maria Teresa Landi emphasized that most lung cancer studies have failed to separate data from smokers and non-smokers, limiting insights into causes for the latter group. “This is an urgent and growing global problem,” she said.
The research highlights the need for targeted prevention strategies and screening guidelines that reflect environmental and genetic risks in vulnerable communities.
See: “Factors linked to lung cancer in never-smokers” (July 15, 2025)
