This page was reviewed under our medical and editorial policy by
Dan J. Raz, MD, MAS, Thoracic Surgeon, City of Hope | Duarte
This page was reviewed on June 1, 2023.
Pollution in the environment, including in the air you breathe and the water you drink, is a major public health concern. For decades, authorities have worked to study and reduce the negative effects of pollution on health, including its relationship to cancer. Air pollution is closely associated with lung cancer, and other kinds of pollution may have an effect on cancer risk as well.
Pollution occurs when harmful substances—known as pollutants—make their way into the air and water. Pollution is largely a human-made problem, resulting from sources such as manufacturing, energy production, farming, flying, driving, shipping and more. Wildfires are another source of air pollution, as are home fireplaces.
Government environmental agencies are tasked with controlling and reducing pollution. Regulations aim to limit the amount of pollution that industries emit, and advancements in technology have helped reduce emissions from other sources, such as cars.
Still, the level and type of pollution vary depending on where you live, and people in communities with high exposure to pollution face serious health effects, including increased risk for certain cancers. For example, residents near high-volume roads or highways may face more exposure to air pollution because of the number of cars and trucks.
Your body is essentially a filter for everything that goes into it. Look to your air and water sources for potential sources of pollution.
Evidence suggests that air pollution from particulate matter—small, airborne particles—may lead to lung cancer, with hundreds of thousands of lung cancer deaths worldwide attributed to air pollution. It’s the second leading cause of lung cancer after smoking, according to a 2020 American Cancer Society review in CA: A Cancer Journal for Clinicians.
The 2020 review also noted some evidence to suggest that air pollution may be a possible cause of other cancers and increase the risk of bladder cancer, breast cancer, kidney cancer, colon cancer and rectal cancer. However, studies regarding these cancers are less conclusive, and research is ongoing. Scientists are also studying whether air pollution may contribute to the risk of childhood leukemia.
It’s unknown exactly how air pollution leads to cancer, but researchers have focused on a few possibilities:
Water is another key source of pollution. Water contaminated with high levels of arsenic is a cause of bladder cancer, and it’s also been associated with skin and lung cancers. Drinking water from private wells was found to be a source of arsenic, according to a study in the Journal of the National Cancer Institute. Nitrates, also found in higher levels in private wells, have been associated with colon, kidney and stomach cancers when combined with higher meat intake.
Scientists continue to research the effects of contaminated water on cancer risk, including whether pesticides (which may also be in the air), disinfectant by-products, per- and polyfluoroalkyl substances (PFAS), and other water pollutants may be to blame.
There are some steps to help reduce the risk of cancer from air pollution, including:
If you drink water from a private well, the Centers for Disease Control and Prevention recommends that you have it checked once every year for contaminants.
Other steps, such as walking or biking rather than driving to work, are most helpful when they’re community-based initiatives—if many people do their part, they may collectively help lower pollution in their area.