Key Takeaways<\/p>\n
A melanoma cluster in Pennsylvania has highlighted a potential link between agriculture and skin cancer<\/p>\n
Regions with more cultivated cropland had more cases of melanoma<\/p>\n
Risk increased with the amount of farm chemicals used in a region<\/p>\n
TUESDAY, Nov. 18, 2025 (HealthDay News) \u2014 A melanoma<\/a> cluster found in the heart of Pennsylvania farm country has highlighted potential links between agriculture and skin cancer.<\/p>\n Adults 50 and older living in a 15-county stretch of south-central Pennsylvania were 57% more likely to develop melanoma than people living elsewhere in the state, researchers reported Nov. 14 in the journal JCO Clinical Cancer Informatics<\/a>.<\/p>\n The risk wasn\u2019t limited to farm workers who spend their days toiling in the sun, either.\u00a0<\/p>\n Risk was higher in both rural and metropolitan areas located near active farmland, and the risk remained even after researchers accounted for residents\u2019 exposure to ultraviolet radiation.<\/p>\n \u201cMelanoma is often associated with beaches and sunbathing, but our findings suggest that agricultural environments may also play a role,\u201d researcher Dr. Charlene Lam<\/a>, an associate professor of dermatology at Penn State Health across several locations in central Pennsylvania, said in a news release.<\/p>\n \u201cAnd this isn\u2019t just about farmers. Entire communities living near agriculture, people who never set foot in a field, may still be at risk,\u201d Lam said.<\/p>\n For the study, researchers analyzed five years of cancer registry data from 2017 through 2021 in Pennsylvania.<\/p>\n They found that counties in the melanoma clusters had more cultivated farmland \u2014 an average of 20% versus 7% for non-cluster counties.<\/p>\n For every 10% in the amount of cultivated land in a region, melanoma cases rose by 14%, results show.<\/p>\n Melanoma also coincided with more use of herbicides, researchers said, with an average 17% of herbicide-treated land in cluster counties versus less than 7% in non-cluster counties.<\/p>\n Every 9% increase in herbicide use corresponded to a 14% increase in melanoma cases, researchers said.<\/p>\n “Pesticides and herbicides are designed to alter biological systems,\u201d senior researcher Eugene Lengerich<\/a>, a professor of public health sciences at Penn State in State College, Pennsylvania said in a news release. \u201cSome of those same mechanisms, like increasing photosensitivity or causing oxidative stress, could theoretically contribute to melanoma development.\u201d<\/p>\n Previous studies have found that pesticides and herbicides heighten sensitivity to sunlight, disrupt immune function and damage DNA in animals and plants \u2014 all of which might increase melanoma risk in humans, researchers noted.<\/p>\n The researchers noted that the risk isn\u2019t limited to farm workers applying herbicides to a field. These chemicals can drift through the air, settle in household dust and seep into water supplies.<\/p>\n \u201cOur findings suggest that melanoma risk could extend beyond occupational settings to entire communities,\u201d Lam said. \u201cThis is relevant for people living near farmland. You don\u2019t have to be a farmer to face environmental exposure.\u201d<\/p>\n Similar patterns have been found in agricultural regions in Utah, Poland and Italy, researchers noted.<\/p>\n However, researchers noted that the new study doesn\u2019t prove a cause-and-effect link between agriculture and melanoma, but only shows an association.<\/p>\n