"Pesticide applicators in North Carolina and Iowa who sprayed the insecticide carbaryl often during their career have a higher risk of getting stomach, esophageal, tongue and prostate cancers, according to new research led by the National Cancer Institute (NCI). 

The research is the first to link the pesticide to stomach cancer, but it builds on many previous studies that have found carbaryl — often marketed under the brand Sevin — increases risk for multiple other cancers. The chemical is used to kill aphids and other insects on various farm crops, as well as insects such as ants, fleas and ticks in turf and home gardens. 

“This is the largest and most comprehensive prospective evaluation of carbaryl and cancer risk to date,” the authors wrote.

The researchers used data from the US government-funded Agricultural Health Study about pesticide use by farmers and other licensed pesticide applicators in Iowa and North Carolina. The data includes self-reported pesticide use from 1993 to 1997 and from 1999 to 2005."

Brian Bienkowski reports for The New Lede July 9, 2025. [2]