Breast cancer is the leading cause of cancer death in women around the world. While genetics play a role in about 10% of breast cancer cases, many researchers are focusing on environmental factors, such as pesticide exposure, to understand other possible causes.
Studies have shown that women who are exposed to pesticides, especially in agricultural jobs, are more likely to develop aggressive forms of breast cancer. One of the main concerns is estrogen-positive breast cancer, which has been increasing in recent years. Scientists believe that chemicals called xenobiotics, including organochlorine pesticides (OCPs), may be influencing this rise.
OCPs are a group of at least 20 different chemicals used in farming to protect crops. These pesticides can be harmful because they interfere with the body’s hormone system by mimicking estrogen or disrupting hormone signaling, which can lead to uncontrolled cancer cell growth. They can also damage DNA, leading to mutations. Additionally, OCPs increase oxidative stress, which can harm cells and make them more likely to become cancerous.
One specific pesticide metabolite, called 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), has been linked to an increased risk of breast cancer in women. These harmful chemicals build up in the environment and enter the food chain, eventually being stored in human fat tissue, blood, and even breast milk.
A large review of 70 studies found that pesticide exposure is linked to a higher risk of breast cancer, especially in women who started their menstrual cycles at a young age. However, the same link was not found in men.
The growing evidence suggests that reducing pesticide exposure could help lower the risk of breast cancer. Choosing organic food, which is grown without synthetic pesticides, is a vital way to reduce exposure and minimize potential health risks. A study involving over 150,000 women and men that looked at the intake of fruits and vegetables and those foods which had high pesticide levels compared to low levels. They found that people who consumed equal to or more than 4 servings of low-pesticide fruit and vegetables daily had a 36% lower all-cause mortality (death) risk. However, people consuming high-pesticide fruit and vegetables all cause-mortality was only 7% lower. The key point is that pesticide laden foods may counteract the benefits of fruits and vegetables on mortality.
References
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