What are forever chemicals?
Forever chemicals are also called PFAS, or per- and polyfluoroalkyl substances, and they include specific compounds such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). PFAS just refers to a class of chemicals that have this carbon-fluoride bond, which is particularly strong and makes it hard to degrade in the environment, but also gives them properties that make them attractive for use in consumer and other products. They take a long time to break down.
How did these chemicals get into our drinking water?
The routes that we know the most about are byproducts of manufacturing. Factories that make PFAS-containing products may have wastewater effluent that goes into the water supply or the bodies of water that provide the water supply for communities. And because the chemicals don't break down and aren't handled by the traditional methods of water treatment, they then show up in drinking water.
The other route, which is probably more important in Colorado, is they're an important component of firefighting foam. When firefighting foam is used either for a real fire or for training purposes, then the PFAS are washed into the groundwater and then get into the water supply. It’s an issue because it’s a very effective approach to firefighting.
There are other routes too. There might be fertilizer sludge that was associated with water supplies that had PFAS in them. Then you spread those over your crops and then the PFAS gets into the crops.
But there are lots of other routes, not necessarily in your drinking water, including water repellant clothing and nonstick pans, fire-retardant or stain-resistant carpet treatment and furniture treatment, and even in women's cosmetics because they're water resistant. We also find them in fast food containers because the grease won't leak through and in comfort dental floss because they slide easily between your teeth.
What are the health risks of PFAS in your drinking water?
Well, the issue is as you drink it, it builds up in your body. And people can have elevated serum levels of PFAS, and that's where we have health concerns.
The National Academies’ Consensus Study actually says that we have enough evidence to say that there's an association (with human health). These fall into two groups – the first where we found that there was sufficient evidence of an association. There were four associations that were strongest, and that includes decreased antibody responses in both adults and children. So, if you get an immunization, the antibody titers you develop are lower if you have high levels of PFAS in your blood. There’s an association with high cholesterol. There's an association with a small decrease in infant and fetal growth, and then there's an increased risk of kidney cancer in adults.
Then there was another group where the evidence was more moderate. It’s a longer list and included breast cancer in adults, testicular cancer in adults, abnormal liver enzymes, an increased risk of pregnancy-induced hypertension, thyroid disease and dysfunction in adults and risk of ulcerative colitis in adults.
How do I know if my water has been contaminated?
We have advantages in that the Colorado Department of Public Health and Environment (CDPHE) has information on water supplies that are municipal water supplies. You can contact your local health department, or you can contact CDPHE, and they can provide information. You can also talk to Denver Water directly because it's been an issue discussed and of interest in Colorado for a while. Colorado has banned the ongoing manufacturing with PFAS moving forward and is trying to address it in all the water supplies.
I think the other route that's not been as quickly developing in terms of availability is actually getting a blood test to see if you have elevated serum levels. Our report for recommendations for clinicians and patients is based on doing serum levels. There’s a low area where you don't need to worry about it. There's also a high area where we think you ought to talk to your clinician about the potential conditions that are associated with high serum levels. And then there's this big range in between the two extremes.
Is there anything you can do if you have high levels in your body?
Even in the body, these PFAS have what we call a half-life. They’ll break down over time.
The National Health and Nutrition Examination Survey (NHANES) is a survey that's done every couple of years, and researchers started including blood testing, and they look at PFAS. And the good news is ever since they've started looking at it, it's been decreasing because the major companies have all stopped making the major PFAS that we have evidence for.
So as those break down, as they will slowly in the environment, they also break down and leave the body over time. The rates are going in the right direction.
Plus, we have screening tests for almost all of the health conditions I talked about earlier. The one we don’t have is kidney cancer. We don't have a known effective screening approach or recommendation for kidney cancer.
Is there anything you would like to add?
Yes, I would be remiss if I didn't say people are studying ways of reducing overall body burden. You can donate blood, and that actually takes out the PFAS with the blood, then you replace it with blood that doesn't have PFAS. You can also have phlebotomy treatment which involves just removing a safe volume of blood.
There's a study in Australia about whether or not giving people blood with PFAS (that is, blood donated by someone with high levels) is a significant health risk. However, if your blood level of PFAS is low, the amount in any blood you are given will be diluted, so the risk may not be significant.
There are even people who are trying binding agents that you can swallow. There are some cholesterol medications that may lower PFAS blood levels over time. But the good news is that unless you have ongoing exposure, your blood levels should come down.
Also, I think it's important that your doctor may be hearing this at about the same time as you are. We're trying to look for ways to educate primary care clinicians to help them and their patients make good decisions. For example, the people you'd want to test will be people who are more likely to have high PFAS in their blood levels, including people who might live around airports or military bases where that firefighting foam might have been used, firefighters or people who work in the industry of producing materials high in PFAS.
If you do check your water and there is contamination, is there something you can do?
Yes, there are water filters that take PFAS out of the water. You just put it on the faucets from where you get water that you're going to drink.