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Our world is full of potential dangers we can’t see with the naked eye. Those include perfluoroalkyl and polyfluoroalkyl substances (PFAS), better known as “forever chemicals.” Although these particles are everywhere, your exposure could vary greatly depending on where you live.
According to scientists at USC’s Keck School of Medicine, certain southern California neighborhoods are associated with higher levels of PFAS in residents’ blood, raising their risk for disease. A number of factors were linked to higher blood levels of PFAS. These include living in a water district with PFAS contamination, living in a neighborhood with low food access, and living within a three-mile radius of a PFAS-polluting facility or Superfund site.
PFAS are manufactured chemicals used in a broad spectrum of consumer products. Some of these include non-stick cookware such as Teflon, food packaging such as microwave popcorn and fast food wrappers, cosmetics, cleaning products, personal care products, and many others. The PFAS are used for their durability. However, they accumulate in the body and take an extraordinarily long time to break down.
PFAS are often referred to as “forever chemicals” because they are extremely resistant to breaking down after they enter the environment. In natural conditions, PFAS can take more than a thousand years to degrade. Even incinerating them at extremely high temperatures releases chemicals into the environment.
PFAS are associated with significant health concerns due to their persistence in the environment and accumulation in the human body. Some of the key medical concerns related to PFAS include:
- Cancer – notably kidney and testicular
- Liver damage leading to fatty liver disease
- Reproductive and developmental issues – decreased fertility, high blood pressure in pregnant women, low birth weight, accelerated puberty
- Thyroid disruption
- Increased cholesterol levels
- Kidney disease
- Cardiovascular disease
- Neurological disorders
Researchers examined whether drinking water, food access, and industrial pollution are linked to PFAS in the blood of 446 residents and their proximity to Superfund sites – areas designated by the U.S. Environmental Protection Agency as contaminated with toxic substances. The results were just published in the journal Environmental Research.
A number of factors were associated with higher blood levels of PFAS. These included living in a district with contaminated water, having low food access, or living within three miles of a Superfund site or PFAS-polluting facility.
Participants in the study were mostly Latino – providing evidence for addressing neighborhood features to reduce ethnic and racial environmental health disparities.
The researchers sought to determine what neighborhood features predict differences in blood levels of PFAS. They enlisted participants from two groups: the study of Latino Adolescents at Risk and the Metabolic and Asthma Incidence Research Study. They obtained residential addresses and blood samples from the participants.
The team determined that people who lived in districts with water supplies containing PFAS had higher blood levels of those substances. They compared these to national averages and found that the increases were substantial.
The scientists also explored the relationship of fresh food access to PFAS levels, since PFAS are common in food packaging. Low fresh food access as a region is defined as a census tract in which more than 500 people, or one-third of the population, live more than half a mile from the nearest supermarket. The participants living in these areas had higher levels of PFAS, probably because they consumed more packaged foods.
Lastly, researchers studied if living near a designated Superfund site or an industrial site that processed PFAS was linked to higher levels of PFAS in blood. For each industrial site processing PFAS, they found that blood levels of PFAS were higher among people within three miles of the site.
New Regulations Are Coming
New EPA rules are changing the way PFAS are regulated. Beginning in 2024, these chemicals are included on the list of hazardous substances, which led to the designation of a “Superfund site” to receive additional funding for toxic waste cleanup. Another new rule, scheduled to take effect in 2029, will regulate the levels of six PFAS in public drinking water.
The Keck School’s Department of Population and Public Health Sciences has launched several projects to share their research findings with the residents of high-risk areas.
The study was funded in part by the National Institutes of Health and the USC President’s Sustainability Research Initiative.
