One in five people will develop some type of cancer during their lifetime, but at least 40% of all cancer cases could be prevented, according to the Cancer Research Center (IARC). Breast cancer is one of the most common cancers worldwide and, in fact, in Spain, around 30% of cancers diagnosed in women have their origin in the breast, according to GEICAM.
Among the risk factors for developing this tumor is exposure to environmental pollutants, many of which can be included in everyday products. Now, a team of scientists has discovered how to predict the likelihood that a chemical will cause breast cancer based on certain traits, which would help quickly identify those that should be removed from consumer products and replaced with safer alternatives. health.
“This new study provides a roadmap for regulators and manufacturers to quickly identify chemicals that could contribute to breast cancer, prevent their use in consumer products and find safer alternatives,” said Dr. Jennifer Kay, research scientist at the Silent Spring Institute and lead author of the study ‘Application of the key characteristics framework to identify potential breast carcinogens using publicly available in vivo, in vitro and in silico data’, published in Environmental Health Perspectives. “We need new tools to identify environmental exposures that could be contributing to this trend, so we can develop prevention strategies and reduce the burden of disease,” adds Kay.
Identify chemicals that cause breast tumors
The researchers searched a large number of US government and international databases to identify chemicals that cause mammary tumors in animals. The databases came from the International Agency for Research on Cancer (IARC), the National Toxicology Program, the US Environmental Protection Agency (EPA), and the National Cancer Institute, among others.
Additionally, they analyzed data from the EPA’s ToxCast program to identify chemicals that disrupt the body’s hormones or endocrine disruptors that could promote breast cancer. They specifically looked for chemicals that activate the estrogen receptor found on breast cells, as well as chemicals that induce the cells to produce more estrogen or progesterone, a known risk factor for breast cancer.
They identified a total of 921 chemicals that could promote the development of breast cancer. 90% of chemicals are included among those to which people are regularly exposed because they are contained in consumer products, foods and beverages, pesticides, medications and work environments.
“This study provides a roadmap for regulators and manufacturers to quickly identify chemicals that could contribute to breast cancer to prevent their use in consumer products.”
A breakdown of the list revealed 278 chemicals that cause mammary tumors in animals. More than half of the chemicals cause cells to produce more estrogen or progesterone, and about a third activate the estrogen receptor. “Breast cancer is a hormonal disease, so the fact that so many chemicals can alter estrogen and progesterone is concerning,” Kay said.
Because DNA damage can also trigger cancer, the researchers searched additional databases and found that 420 of the chemicals on their list deteriorate DNA and alter hormones, which could make them more dangerous. Additionally, they noted that chemicals that cause mammary tumors in animals are more likely to have these DNA-damaging and hormone-disrupting characteristics than those that do not.
“Historically, chemicals that cause breast tumors in animals were considered the best predictor of whether they would cause breast cancer in humans,” said co-author Ruthann Rudel, research director at Silent Spring. “But animal studies are expensive and time-consuming, which is why not as many chemicals have been tested. “Our findings show that screening chemicals to identify these hormonal traits could be an effective strategy to detect potential breast carcinogens.”
This new study could have implications for how the EPA evaluates the safety of chemicals. For example, the chemicals identified in the study include more than 30 EPA-approved pesticides despite evidence linking the chemicals to breast tumors. Therefore, its authors hope that the EPA will take into account the new complete list of chemicals relevant to breast cancer, which includes hundreds of endocrine disruptors, to better protect the population from harmful exposures.
