PFAS Toxicity – Their Impact on Human Health

Per- and polyfluoroalkyl substances (PFAS) are a large group of synthetic chemicals that have been in use since the 1940s. They are widely recognized for their oil- and water-resistant properties, which make them valuable in a variety of industrial and consumer products such as non-stick cookware, water-repellent clothing, food packaging, and firefighting foams. Despite their utility, PFAS toxicity has become a significant environmental and public health concern due to their association with cancer and other health risks. Although it’s well-known that PFAS are harmful, many people are unaware of how exactly PFAS affect human bodies, and which substances cause the most harm.

Is PFAS Toxicity Linked with Cancer?

Studies have shown that certain PFAS can disrupt endocrine function, alter hormone levels, and even affect immune response — all of which are factors that can contribute to carcinogenesis.

PFAS are believed to cause cancer through several mechanisms:

1. Hormonal Disruption

PFAS can mimic or interfere with hormones in the body, particularly thyroid hormones, which are critical in regulating metabolism, growth, and development. Disruption of these hormones can lead to abnormal cell growth and potentially cancer, particularly thyroid cancer.

2. Oxidative Stress

PFAS exposure can increase the production of reactive oxygen species (ROS) in the body. High levels of ROS can damage cellular components such as DNA, proteins, and lipids, potentially leading to mutations and cancer development.

3. Immune System Suppression

PFAS have been shown to impair the immune system, which is vital for identifying and eliminating abnormal cells, including cancer cells. A weakened immune response can allow these abnormal cells to proliferate unchecked, increasing cancer risk.

4. Liver PFAS Toxicity

PFAS can accumulate in the liver, disrupting the organs functioning and potentially leading to liver cancer. The liver is a critical organ for detoxification, and its impairment can exacerbate the accumulation of harmful substances in the body, further increasing the risk of cancer.

Long-Chain vs. Short-Chain to Consider for PFAS Toxicity

A significant feature of this group of molecules is the carbon-fluorine bond. The carbon-fluorine bond is one of the strongest in organic chemistry, making PFAS highly resistant to environmental degradation. This same bond strength also contributes to their persistence in the human body, as they are not easily broken down or excreted.

We categorize PFAS into long-chain and short-chain compounds based on the number of carbon atoms in their molecular structure. The longer the carbon chain, the more resistant the compound is to metabolism and elimination, leading to greater bioaccumulation and prolonged exposure to toxic effects. Long-chain PFAS, such as PFOA and PFOS contain more than six carbon atoms in their molecular chain.

Due to their smaller size, kidneys can more easily excrete short-chain PFAS than long-chain PFAS. As a result, short-chain PFAS do not accumulate in the body to the same extent. However, this does not necessarily mean they are harmless. While we often market short-chain PFAS as safer alternatives to long-chain PFAS, emerging research suggests that they may still have significant health impacts, including potential endocrine disruption and liver toxicity. The extent of these effects is not yet fully understood.

In addition, PFAS are both hydrophobic (water-repellent) and lipophilic (fat-attracting), which means they tend to accumulate in fatty tissues. This characteristic is particularly concerning because fatty tissues are present throughout the body, including in vital organs such as the liver, kidneys, and brain. Accumulation in these tissues can lead to chronic exposure, even if we reduce external exposure.

PFAS Regulations

Globally, governments have implemented various regulations to control the production, use, and disposal of PFAS:

In the United States, the Environmental Protection Agency (EPA) plays a central role, issuing health advisories for PFAS levels in drinking water and regulating these chemicals under the Toxic Substances Control Act (TSCA). Several states, such as California and New Jersey, have also set their own, often stricter, limits on PFAS in drinking water and have banned their use in specific products like food packaging. Learn more about state-wide PFAS regulations.

The European Union regulates PFAS under the EU REACH (Registration, Evaluation, Authorisation, and Restriction of Chemicals) framework, which classifies certain PFAS as substances of very high concern (SVHC). The EU is moving towards phasing out non-essential uses of PFAS by 2030. Additionally, the revised Drinking Water Directive sets limits for PFAS levels in drinking water.

Internationally, the Stockholm Convention on Persistent Organic Pollutants has included some PFAS, like PFOS, in its list of restricted substances, requiring countries to limit their production and use.

PFAS are a class of chemicals with significant environmental persistence and potential health risks. As regulations surrounding PFAS become stricter, it’s vital to ensure that the products you buy and sell are free from these harmful substances.

If you need help reaching PFAS compliance, contact Enviropass for a free consultation.