Stricter limits for permanent chemicals pose challenges | New


June 22, 2022 – On June 15, the Environmental Protection Agency (EPA) released an update health notice warning that even small amounts of two types of synthetic compounds, PFOS and PFOA, are harmful to humans. Currently, these compounds are found in drinking water systems across the United States. Philippe Grandjeanassistant professor of environmental health at Harvard TH Chan School of Public Health, discusses the new guidelines.

Q: Can you describe the new EPA notices and their implications?

A: The EPA has issued guidelines with new limits for the amount of PFOS and PFOA in drinking water. These two compounds are part of a larger class of chemicals called PFAS – per- and poly-fluoroalkyl substances – which are also known as “eternal chemicals” because they do not break down in the environment over time. time. These chemicals have water and grease resistant properties and are used in a wide variety of products including non-stick cookware, waterproof clothing, food packaging and fire fighting foams. Exposure to PFAS has been linked to health problems such as kidney and testicular cancer, weakened immunity, endocrine disruption, fertility problems and reduced birth weight.

The previous guideline, established in 2016, set a limit of 70 parts per trillion (ppt) for PFOS and PFOA in drinking water. New reviews diminish this by more than a thousand times. The new limit for PFOS is 0.02 ppt; for PFOA it is 0.004 ppt. Essentially, the EPA wants the limits to be as close to zero as possible because a growing body of research has shown how toxic these compounds are.

These new advisories are exactly in line with the findings of some of our previous studies, which have shown some of the serious health issues associated with PFAS exposure. For example, our 2012 study showed that children with the highest exposure to PFAS responded less well to routine childhood vaccinations against diphtheria and tetanus. We found that when exposure to PFAS was doubled, children lost 50% of the antibodies they should have had from their vaccinations, meaning that more and more of them were not sufficiently protected against these diseases.

Our research also showed that children with higher levels of PFAS at birth – we measured levels in cord blood – had lower antibody levels in response to subsequent vaccinations. In addition, PFAS is transmitted through breast milk. Unfortunately, the baby can end up with up to 10 times more PFAS in the blood than the mother.

The EPA decided that since children are born with PFAS in their bodies and get it from breast milk, they needed to find a way to limit general population exposure to protect pregnant women. It was really inventive. This is the first time I know of a US regulator deciding to protect the child by setting an exposure limit that takes into account the exposure of the mother.

Q: A recent Article from USA Today noted that the new advisories “stunned” scientists and officials across the country. Why were people so surprised by the EPA’s decision?

A: What is surprising is that the drop is very, very significant. We are talking about concentrations of PFAS in water that are very difficult, if not impossible, to measure with our current methodologies and instruments. I think it is quite possible that we can measure these concentrations accurately, but it will take time to develop new methods.

The new EPA advisories also create some uncertainty and confusion. The EPA says it’s important that PFAS contamination in drinking water be as close to zero as possible. I agree. But the problem is that there is no way yet to obtain drinking water in accordance with the new limit. At least 100 million Americans drink water with PFAS levels likely exceeding the current limit of 70 ppt. Since the guidelines are not legally binding, it is unclear what difference they will make. If a community wants to pursue a particular source of PFAS contamination, can they rely on EPA guidelines? Would they carry weight to inspire better prevention at state and community levels?

Additionally, a number of states, including Massachusetts, New Hampshire, Vermont, Michigan, New Jersey, and California, have lowered their guidelines on the amount of PFAS that can be found in drinking water and, in some cases, these limits are legally binding. They are below 70 ppt but well above the very low limits that the EPA has just announced. EPA guidelines could be a goal, but it would be more useful to have a binding intermediate limit for PFAS that we should meet in the short term.

Q: The EPA has also issued final health advisories for compounds known as GenX and PFBS, which are considered substitutes for PFOA and PFOS, respectively. What can you tell us about these?

A: The limits for these two substances are higher than those for PFOS and PFOA because there are no human studies yet showing their harmful effects. It is almost certain that the guidelines issued by the EPA for these substances are far too high.

There are probably thousands of compounds similar to these four, and they are unregulated. What’s happening is that the industry—for example, for the firefighting foam known as AAAF—just uses other PFAS instead of PFOA or PFOS. It’s called regrettable substitution, when you ban one type of chemical and then get something that may be just as bad or worse.

Some EU member states are working with the European Commission to find a way for member states to regulate essentially all of these PFAS. So there is a political movement to generate some sort of legislation that can protect Europeans from alternatives to PFAS.

Many colleagues have expressed frustration that we in the United States, as well as abroad, are still discussing how to control “old” PFAS, when we haven’t had time to document new ones. substitutes. It can take decades. Should we in the meantime allow new PFAS to enter the environment and ourselves while the scientific evidence develops? As a physician, I would stress the need for careful prevention and a strategy that protects us against the whole family of PFAS.

Karen Feldscher


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