The science is clear: dozens of chemicals found in indoor and outdoor environments contribute to cancer. This evidence is based on comprehensive reviews by authoritative scientific bodies, including the World Health Organization’s International Agency for Research on Cancer (IARC) and the U.S. National Toxicology Program (NTP).
Cancer develops from a combination of genetic and external risk factors, a series of interactions, much like electric circuitry, where many components need to be in place to cause a light to turn on. In the case of environmental chemicals, exposure to any one pollutant may pose only a small increased risk of cancer in an individual, but if exposures to that pollutant are widespread and occur in most people, even small increases in individual risk can result in significant numbers of cases in the general population. In addition, when many people are exposed to multiple substances that increase cancer risk to varying degrees in various ways, that too can result in significant numbers of cases in the population. The more a population is exposed, the greater the number of cases of cancer that can be prevented by reducing those exposures.
A Science Companion document produced by the Network reviews the state of the science related to the contribution of environmental and occupational chemicals to cancer, with a specific focus on risk factors that are elevated in Southwestern Pennsylvania. Environmental chemicals and pollutants of particular concern in our region are priority environmental risk factors.
CENSWPA issues a monthly Digest each month, which includes a list of research articles published the prior month. The Science Support Workgroup of the CENSWPA reflected on the 2021 collection of articles and identified the following noteworthy themes:
- A range of additional types of cancers, not just lung cancer, show associations with exposure to air pollution.
- Research on causes of childhood cancers continue to substantiate risks associated with exposure to pesticides and air pollution. However, there is a paucity of research on topics of notable interest to CENSWPA, including risks to children from fracking and specific pesticides of concern, such as glyphosate.
- Exposure to emerging contaminants in the environment, such as per- and polyfluoroalkyl substances (PFAS), are demonstrating cancer risks.
- 2021 did little to fill a gap in the research literature: the effectiveness of a range of interventions to reduce environmental exposures associated with cancers.
Read the Network’s “A Year in Review- Reflections on 2021 Peer-Reviewed Research on Cancer and Environment” to learn more about these themes.