Living in areas with high agricultural pesticide exposure is associated with higher cancer risks, according to a new study that highlights potential health impacts in vulnerable communities. Researchers found that widespread exposure to pesticides in food, water and the environment may increase the likelihood of developing certain cancers.
The study, published in Nature Health, analysed environmental data, cancer registries and biological samples across Peru. It found a strong association between pesticide exposure and cancer risk, marking one of the first large-scale efforts to connect environmental contamination with biological changes linked to the disease.
“This is the first time we have been able to link pesticide exposure, on a national scale, to biological changes suggesting an increased risk of cancer,” said Stéphane Bertani, a molecular biology researcher at the French National Research Institute for Sustainable Development.
The research was conducted in collaboration with several institutions, including the Institut Pasteur, the University of Toulouse and Peru’s National Institute of Neoplastic Diseases. Scientists mapped pesticide dispersion across the country over a six-year period from 2014 to 2019, identifying regions with the highest exposure levels.
The findings showed that people living in these high-risk zones were about 150% more likely to develop cancer. Areas of moderate to high exposure covered more than one-third of Peru’s territory, with contamination spreading up to 30 to 50 kilometres beyond agricultural land due to environmental factors such as wind and terrain.
The study examined data from more than 150,000 cancer patients diagnosed between 2007 and 2020. The highest exposure levels were found in the Andean highlands, where limited rainfall can intensify the accumulation of chemicals. Researchers noted that even pesticides not classified as carcinogenic by the World Health Organization may still contribute to harmful biological changes over time.
Laboratory analysis revealed that pesticide exposure can disrupt cellular processes that help maintain normal function. These disruptions may occur long before cancer develops, potentially increasing vulnerability to other risks such as infections or inflammation.
The study also found that certain cancers were more closely linked to pesticide exposure, particularly epithelial cancers affecting the digestive system, lungs and skin. In Peru, cases of liver cancer were found to overlap with regions of heavy pesticide use, raising questions about environmental factors contributing to the disease.
Researchers said the findings highlight the challenges of tracking pesticide exposure, given its widespread presence in ecosystems. They also warned that communities with limited healthcare access and intensive agricultural activity may face greater risks.
The study calls for stronger regulatory policies and improved monitoring to address environmental health risks. Experts say understanding how pesticide exposure affects human biology could play a key role in preventing cancer and protecting at-risk populations.
