UCSF Links Microplastics to Cancer and Reproductive Health Risks
Microplastics - particles less than five millimeters - can be found everywhere: in Arctic glaciers, deep-sea sediment, as well as human and animal tissue. Recent studies suggest that, along with greenhouse gas emissions and other human-made pollutants, that’s not a good thing. University of California, San Francisco School of Medicine professor of obstetrics, gynecology, and reproductive sciences, Tracey J. Woodruff, PhD, analyzed 3,000 studies of microplastic exposure and links to respiratory, digestive, and reproductive health. In an article published last year in Environmental Science & Technology she reported that most of the analyses were based on laboratory experiments with rodents that mimic environmental exposures to microplastics. While imperfect, they provide a solid reference for what might be happening in the human population.
“Microplastic exposures increase the risk of reproductive outcomes, particularly male sperm quality, and increase the risk of biomarkers that we know are linked to cancer in both the colon and the lung,” stated Woodruff.
Plastics are ubiquitous. Since the 1950s humans have produced eight billion tons of the material to make medicines, clothes, packaging, and building supplies. A visit to a hospital, where each needle is sterile packaged in UCSF Links Microplastics to Cancer and Reproductive Health Risks plastic, or a stroll down a grocery store aisle showcases plastics’ pervasiveness. As it breaks down in landfills or through weathering small particles are released into the environment, which can be absorbed into the body through contaminated food, water, and air. Water filtration systems and indoor air filters can provide some protection.
“Any situation in which you can reduce or eliminate an exposure is an opportunity to prevent disease and protect health,” said Rachel Massey, Senior Science and Policy Lead at the nonprofit Collaborative for Health & the Environment. “There are many sources of exposure, but even removing one toxic exposure can have a significant prevention benefit. Examples can include avoiding microwaving food in plastic or avoiding clothing that gives off microplastic particles in the laundry.”
“The goal is to think about how to reduce your interaction with plastics generally. Try to reduce your use of plastic related containers, avoid highly processed or prepared packaged foods. Use fresh fruits, vegetables, and foods lower on the food chain,” said Woodruff. “Microplastics can be more concentrated in fish so people fishing in the Bay may be exposed to more microplastics.” Tires are a major contributor to microplastic pollution, as particles are released when the rubber hits the road.
“One thing that we can do at the community level is avoid using waste tires in recreational and landscaping applications. Tires are used unfortunately as infill in artificial turf; they’re also used in playground surfacing, and in some cases used in landscaping applications such as walkways or at the base of trees,” said Massey.
Massey and Woodruff suggest reducing plastics in building materials as another way to decrease pollutant levels. California has passed legislation in an attempt to decrease microplastic exposure. Assembly Bill 888, enacted in 2015, restricts plastic microbeads in cosmetics. Other bills require microplastics monitoring by the State Water Resources Control Board and development of a Statewide Microplastics Strategy by the California Ocean Protection Council to prevent microplastic contamination of waterways. At a 2022 United Nations Environmental Assembly, 175 nations voted to adopt a global treaty on plastic pollution, which is still being negotiated. The treaty’s goal is to create a “legally binding instrument on plastic pollution, including the marine environment.”
“The science often lags behind the exposure. So often we don’t start learning about the health effects of a given substance until it’s being found in our bodies. Additionally, policy generally lags behind the science. So, even when we know a fair bit about a toxic exposure, it then takes a very long time to see policy action,” said Massey.
“We also say, this is not your fault. This is a product of the fossil fuel industry,” said Woodruff. “It’s not possible for an individual to control environmental exposure, and it really needs to be collective action and the government to businesses and households.
