Women exposed to long-term polluting fumes have a higher risk of developing breast cancer.
- Natural phenomena (volcanic eruptions, forest fires, etc.) but above all human activities (industry, transport, agriculture, residential heating, etc.) are the source of pollutant emissions, in the form of gases or particles, into the atmosphere. .
- Air pollution kills 8.8 million people a year, including 67,000 in France.
A new study, conducted by French researchers from the Center Léon Bérard, clearly demonstrates the impact of long-term exposure to BaP (benzo[a]pyrene) on breast cancer.
Awareness of the impact of air pollution on health
A real step forward, according to Amina Amadou, first author of the article and researcher in the Cancer Prevention and Environment Department of the Léon Bérard Center. “Awareness of the impact of air pollution on health is growing. While the effects on health in general are well known (reduction in life expectancy, increase in mortality), the links with different cancers, in particular breast cancer, have not been established”, she explains in the preamble.
The benzo[a]pyrene (BaP) is an endocrine disruptor formed during the incomplete combustion of organic matter (poorly controlled combustion of wood, burning of plants in the open air, automobile exhaust gases or cigarette smoke, for example).
The paths of nearly 100,000 women analyzed
In this project, the research team assessed associations between BaP exposure and breast cancer risk in the general population, based on women’s menopausal status, molecular subtypes, stage and the degree of breast cancer differentiation. “This was a cohort of approximately 100,000 women born between 1925 and 1950, followed since 1990. Every 2 to 3 years, they completed and returned paper questionnaires”, details Amina Amadou. “They were questioned about their lifestyle (diet, physical activity, sedentary lifestyle, tobacco, alcohol, taking medication, hormonal treatments, etc.), their environment, their residential history (living and working places), and on the evolution of their state of physical and mental health”, continues the researcher.
Overall, cumulative exposure to BaP was significantly associated with an increased risk of breast cancer. This risk varies with menopausal status, hormone receptor status, and degree of breast cancer differentiation. For example, in women who have undergone a menopausal transition (i.e. premenopausal women at inclusion in the cohort who were postmenopausal at the time of breast cancer diagnosis), exposure to BaP increases the risk of breast cancer by 20%.
Limit emissions of atmospheric pollutants
“The results of this study give arguments to limit the emissions of atmospheric pollutants, in particular pollutants having effects of endocrine disruptors (which can impact the hormonal balance of women)”, concludes Amina Amadou.
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