A new study suggests that people living in areas with heavy pesticide use may face a significantly higher risk of cancer.

Researchers found that individuals in high-exposure regions had about a 150% greater cancer risk compared with those living in areas with lower pesticide use. The study also indicates that combined exposure to multiple pesticides may be harmful — even when each individual chemical falls within established safety limits.

According to ScienceDaily, the study, published in Nature Health, combined environmental monitoring data, national cancer registries, and biological research to better understand how pesticides may damage cells years before cancer develops.

Scientists from France and Peru examined how multiple pesticides — commonly found in food, water, and the surrounding environment — interact and affect people under real-world conditions.

Peru was selected as the focus of the study due to its diverse agricultural practices and climate, which offer a wide range of environmental exposures. Cancer rates are rising in the country, particularly in communities where pesticide levels are high.

Researchers found that in some Indigenous communities, residents were exposed to as many as 12 different pesticides at elevated levels. The analysis included 31 commonly used pesticides, none of which are currently classified as carcinogens by the World Health Organization.

"We first modeled the dispersion of pesticides in the environment over a six-year period, from 2014 to 2019, which allowed us to create a high-resolution map and identify areas with the highest risk of exposure," said researcher Jorge Honles, of the University of Toulouse.

The team then compared that map with data from more than 150,000 cancer patients recorded between 2007 and 2020. The results showed that regions with higher pesticide exposure also had higher cancer rates. In those areas, the risk of developing cancer was about 150% higher than average.

The study also suggests that pesticide exposure may affect the body long before cancer is diagnosed. Researchers say the liver, which plays a key role in processing chemicals, can be disrupted by pesticides, interfering with its ability to filter toxins effectively.

Over time, these changes may weaken tissues and increase vulnerability to inflammation, infections, and environmental stress.

Although the research focused on Peru, scientists say the findings have global implications, highlighting how environmental exposure, agricultural practices, climate conditions, and social inequality may all play a role in long-term health risks.

Researchers say further studies are needed to develop better prevention strategies and more equitable public health policies that address real-world exposure to environmental chemicals.