Living in a polluted area could increase your risk of breast cancer, a new study has revealed.
Researchers at the National Institutes of Health (NIH) discovered breathing in high quantities of particulate matter carries an eight percent rise in the chance of developing breast cancer.
It is abundant in areas packed with vehicle exhaust, oil or coal combustion, wood smoke and vegetation burning, and industrial emissions.
Particulate matter is a mixture of solid particles and liquid droplets found in the air, and the offending particles are just 2.5 microns in diameter (PM2.5) – small enough to inhale deep into the lungs.
The women in the study tended to develop the most common type of breast cancer in the United States, a tumor that progresses slowly.
Dr. Alexandra White, lead author and head of NIH’s National Institute of Environmental Health Sciences, said: “We observed an eight percent increase in breast cancer incidence for living in areas with higher PM2.5 exposure.
“Although this is a relatively modest increase, these findings are significant given that air pollution is a ubiquitous exposure that impacts almost everyone.
“These findings add to a growing body of literature suggesting that air pollution is related to breast cancer.”
In one of the largest studies on the topic to date, the team used data from a study on the diet and health of 500,000 men and women.
They spent around 20 years following them, who had an average age of 62, and during that time 15,870 were diagnosed with breast cancer.
Researchers estimated how concentrated the PM2.5 levels were at each participant’s home, and focussed on the air pollution 10-15 years prior to the study given how long it takes for cancer to develop.
Previous studies have measured air pollution levels around the time participants enrolled in the study, rather than historically.
Senior study author Dr. Rena Jones, from the National Cancer Institute, also part of NIH, said: “The ability to consider historic air pollution levels is an important strength of this research.
“It can take many years for breast cancer to develop and, in the past, air pollution levels tended to be higher, which may make previous exposure levels particularly relevant for cancer development.”
The women came from California, Florida, Pennsylvania, New Jersey, North Carolina, or Louisiana, or from metropolitan areas in Atlanta and Detroit.
Scientists found air pollution was more likely to cause estrogen receptor-positive (ER+) tumors.
According to the American Cancer Society, these grow at a slower rate, tend to have a better outlook, and can be treated with hormone therapy drugs.
They had less of an effect on estrogen receptor-negative tumors.
The team thinks this suggests pollution prompts breast cancer through disrupting hormones in the body, through the endocrine system which releases them.
Next they are keen to study how the different types of air pollution could impact the chance of developing breast cancer.
The study was published in the Journal of the National Cancer Institute.
Produced in association with SWNS Talker
