How New Jersey tamped down PFAS in drinking water

IRA FLATOW: Hi, this is Ira Flatow, and you’re listening to Science Friday. Nearly every one of us has some type of PFAS, commonly known as forever chemicals, in their blood. These chemicals are found in nonstick pan coatings, waterproof materials, and firefighting foam. Roughly two years ago, the EPA adopted federal regulations for PFAS levels in drinking water, though last year the Trump administration rolled back some of those regulations.

But back in 2018, New Jersey was the first state to adopt its own drinking water standards for PFAS. And now, 10 years later, researchers at Rutgers University have crunched the data to see how well it worked. Joining me now to tell us more is the lead author of the study, Doctor Hari Iyer, Assistant Professor of Cancer Epidemiology and Health Outcomes at the Rutgers Cancer Institute of New Jersey, based in New Brunswick, New Jersey. Welcome to Science Friday.

HARI IYER: Thanks so much, Ira. It’s so great to be here.

IRA FLATOW: Nice to have you. OK, let’s jump right in. What did you find in this study?

HARI IYER: We’re so excited to present these results of an evaluation of state policies to reduce PFAS levels in drinking water, and we found a 55% reduction in average concentrations after the policy was implemented.

IRA FLATOW: Wow. Is that a surprising study? I mean, that’s a pretty big drop.

HARI IYER: So it’s interesting you ask that. Our government colleagues were not surprised. They said, Hari, we know when we put these policies in place, we expect to see a drop. That’s why we do them.

But I think we were excited to see this because, in public health, often our message is, this thing is bad for you. This disease is becoming more prevalent. But here we were actually able to demonstrate a positive impact of a regulation.

IRA FLATOW: So would you describe the PFAS in the water now at a safe level in New Jersey?

HARI IYER: So we definitely have observed levels that are below the maximum contaminant levels that are called these regulatory limits. But I think that there’s another part of this story, which is the ongoing evolution of our understanding of the health impacts of long-term exposure.

And so something that a lot of folks will ask is, that’s great that the water levels have dropped today, but have I been drinking water for the last 20 years that has had higher levels? And if so, how does this help me? And I think that that’s a very fair question to ask. And so I think when you asked the question about safe levels, I think we’re still kind of understanding these long-term health risks.

IRA FLATOW: Yeah, so we don’t what those long-term health risks are. Do we know what portion of our daily ingestion of PFAS comes from drinking water?

HARI IYER: So that’s a complicated question. It’s a good one. But what I will say is, based on a lot of this accumulating evidence from animal studies and from toxicology studies in cells, what has been shown is that once water is ingested into the body, the concentration in the water can be magnified by orders of magnitude. And so while I don’t know if I have a precise answer of what contribution water is, it is certainly a very important one. And because of this biological magnification effect, it’s still a major area that we want to control.

IRA FLATOW: Yeah, I want to dig into that more. So what happens when you drink the PFAS in? And how does your body, as you say, magnify what’s going on?

HARI IYER: That’s a great question. I can speak a bit more to the health side than the consumption side. So on the health side, I think what has started to become more evident is that the water passes through your body and usually gets filtered in the kidney and liver. And so those are the organs where some of the best established emerging evidence on a health impact seems to be.

So kidney function and risk of kidney cancers have been linked to these PFAS exposures. And a lot of liver enzyme levels that sometimes you get monitored at the doctor’s office, those seem to be elevated in people who have high consumption of these chemicals. And so some of what we’re doing at the Cancer Institute and in other places is now trying to understand those elevated levels, are they being linked now to these downstream cancer outcomes and other chronic disease outcomes?

IRA FLATOW: How did New Jersey limit the PFAS? Did they have special treatment plants or filters?

HARI IYER: I’m glad you asked that question because it turns out that there were a lot of actions that we observed when we were reviewing these data, actions taken by water systems in anticipation of the policies coming into place. Some examples of some of those actions are identifying wells that have really excess levels and then just pulling them offline, so they’re no longer going to be serving people at their home.

Another example is kind of what you had just asked about, which are granulated activated carbon. It allows us to identify these PFAS chemicals, catch them, and remove them from the water. So post-treatment, those levels are no longer as high.

IRA FLATOW: When you said well water, were you talking about people’s individual well water? They were able to eliminate the PFAS from that?

HARI IYER: So no, no, in this context, what I was referring to is that often water that is provided from different systems, they will have their own wells that are sources of water that then gets transferred. Unfortunately, one of the limitations of our study is that it was really only looking at public water systems. And so unfortunately, we’re not able to demonstrate that this 55% reduction holds in people’s home well systems because those don’t tend to be tested as often. And that’s about 1 in 10 New Jersey residents, I believe, is served by their home well.

IRA FLATOW: So is New Jersey’s water more contaminated than other states?

HARI IYER: So unfortunately, there’s been a nationwide studies that have looked at levels over the last 15 years or so, and yes, unfortunately, New Jersey has in the past had higher levels on average than other states. However, given the findings from this study, one would hope that, in subsequent years, when those national comparisons are done, that may not be the case.

IRA FLATOW: Yeah. Are other states looking at your success and implementing their own standards for PFAS?

HARI IYER: That’s a great question. And that’s something that we hope that other states can look to some of these successes. But I think the power of doing something like this and being able to publish these findings is that it can lead to exactly what you’re describing.

Best practices can be shared from states. These experiments that are done at a local level, you can test some of the kinks in the policy. Maybe it works well in certain contexts but not others. Maybe it’s addressing certain populations and not others. And those best practices can be shared to ultimately make our drinking water safer for everybody.

IRA FLATOW: Doctor Iyer, I know you’re a cancer researcher, and I’m wondering how you got interested in studying PFAS in drinking water.

HARI IYER: So I’ve been studying prostate cancer since my since my doctoral training, and one of the biological pathways that drives prostate cancer is sex hormone disruption. And so endocrine-disrupting chemicals have long been thought of as a potential risk factor. But there’s been very few human epidemiologic studies that have robustly demonstrated this, have replicated in different populations.

So when I moved to New Jersey to start my job as an assistant professor here, one of the first things I did was talk to you environmental health scientists at our university who have been studying not just forever chemicals, but lead levels. And I think it was really through conversations with them, learning more about the state, learning more about some of the health challenges that I became aware of it. And it seemed like it was a very important question, not just from a scientific side, but one that the residents of New Jersey are very concerned about.

IRA FLATOW: So what’s next for your research here? I imagine, since we don’t know a lot about the long-term effects, that you’re interested in that.

HARI IYER: Yeah, so I think that the evidence right now has demonstrated a lot of these biomarkers, like we talked about, liver enzymes and kidney function. And lipid levels and cholesterol levels are another area. But demonstrating these cancer pathways is incredibly difficult from a design perspective because you have to follow people for many, many years, and you have to get a really strong understanding of what their exposure was not when you’re talking to them today, but 10 years in the past.

And so our lab is conducting a few studies right now trying to reconstruct those historical PFAS levels by using some of the data that we presented in this study and developing predictive models predicting the PFAS levels 15-20 years ago in different parts of New Jersey. What we can do then is we can link those predictions to people’s homes and where they may have moved over the course of their lives to be able to get a better measure of what that exposure may have been at a time when that cancer may have been developing.

IRA FLATOW: Whenever I think about PFAS or other carcinogens or potential carcinogens that we don’t know about, that take years to develop, I think about asbestos that we all sucked in for half a century–

HARI IYER: Yeah, yeah.

IRA FLATOW: –from our car brakes and had no idea of how toxic it was. Could we be facing the same kind of thing with PFAS?

HARI IYER: Yeah, yeah, it’s a really important point. And with PFAS, I think it’s also important when you think about this and put this in the historical context, when these chemicals were first used, they had a lot of really desirable properties. It’s great to be able to fight fires. These plastic linings on the food that kept them preserved were important things at the time.

I think with the story of PFAS and asbestos and some of these chemicals has shown is that there’s likely a balance that can be found in doing some evaluation of chemicals when they first come on the market, where we don’t fully understand what those long-term health outcomes are. But finding that balance, I think, is something that the PFAS story shows that we may have skewed too far on the side of technological progress, we’ll worry about the problems later.

IRA FLATOW: Doctor Iyer, I want to thank you for taking time to be with us today.

HARI IYER: Thank you so much, Ira. It was great to speak with you.

IRA FLATOW: Good luck with your research. Doctor Hari Iyer, Assistant Professor of Cancer Epidemiology and Health Outcomes at the Rutgers Cancer Institute of New Jersey, based in New Brunswick. If you’re listening and worried about PFAS in your drinking water, we have a list of resources on how to effectively filter out forever chemicals from your tap. Head to sciencefriday.com/pfas. That’s sciencefriday.com/pfas.

This episode was produced by Shoshannah Buxbaum. Do you have a question you want us to look into? Please, our listener line is always open. Give us a call at 1-877-4-SCIFRI. 1-877, the number 4, SCIFRI. I’m Ira Flatow. Thank you for listening.

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