From The Editor | March 9, 2023

A Big-Picture Approach To Water Regulations


By Kevin Westerling,

Janet Anderson

A Q&A with human health toxicologist and environmental risk assessor Janet Anderson, Ph.D., DABT

I went into my interview with Janet Anderson, Ph.D., a principal at GSI Environmental Inc. who also recently joined the Water and Health Advisory Council, with plans to discuss drinking water regulations from the standpoint of cold, hard numbers — maximum contaminant levels for dangerous and emerging contaminants such as per- and polyfluoroalkyl substances (PFAS). That’s what a toxicologist would want to talk about, no?

To that extent, Anderson is certainly equipped, and the topic is explored. But she is also an expert on risk assessment and risk management, which informs her input on rulemaking as much as the toxicology part of her job. Understanding and reducing contaminant exposure is a vital safety measure, of course, but how many other factors within the scope of water management affect the human health condition?

During our conversation, I was enlightened — as I hope you will be — by Anderson’s risk-based regulatory philosophy, which looks at water issues holistically to arrive at solutions that provide the greatest overall health benefit. Should this approach be embraced on the federal level and utilized locally in the manner Anderson describes, it would be a win for public health — and for common sense.

The following has been edited for clarity and conciseness.

What role do you serve for the Water & Health Advisory Council and GSI Environmental?

My job is to translate science and help all stakeholders understand how regulatory and public health agencies are looking at the science to inform decisions, and what that means in terms of human health risk. I study risk — of exposure and potential adverse effects — and the combination of those two gives us an understanding of what might be a risk to human health.

What other factors are regulatory and public health agencies considering when determining regulations?

Safe Drinking Water Act requirements for deriving a final MCL, or maximum contaminant level, take into account how we’re going to treat contaminants and the cost implications for that treatment. Those aren’t my areas of expertise, but that’s why it’s important to bring together different disciplines. It’s all related, and the general public is faced with a multitude of risks. It’s not just water contamination; it may be having access to water in the first place.

As a toxicologist, I think about cumulative or multiple potentials for concern. As a nation, we haven’t adequately addressed some of those fundamental and basic issues — access to clean water and infrastructure challenges. I think those issues need to be brought to the discussion of any new regulation, for sure.

How are those different considerations weighed or prioritized?

The prioritization of what is most impactful to a given community must be decided at the state and, even more so, at the local level. That’s why we have differing MCLs, because: 1.) we have differing interpretations of the science; and 2.) we have various tools for the states to use — different resources at their fingertips to make these decisions, and therefore different policies and programs written into state statutes. They also have different priorities beyond MCLs. Some look at their communities and prioritize fixing infrastructure, while others are going to prioritize measures for managing water resources.

Unfortunately, resources, time, and — most importantly — finances are not infinite. And so a cost-benefit analysis discussion is key, and that happens at the local level. The more we can implement federal policies that allow flexibility and allow for regulations that provide the greatest good for the greatest number of people, the closer we get to the ultimate goal.

What do you mean by regulatory “flexibility?”

It comes back to a cost-benefit analysis at the local level. For example, the American Water Works Association (citing Black & Veatch1) estimated upwards of $50 billion to comply with potential perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) regulations. What if, for half of that, we could have the same level of public health protection, but the other half could be spent on infrastructure, on addressing lead, on addressing arsenic, or addressing access to water? It’s not an “either/or,” it’s an “and.” How can we come up with regulations that are an “and” — that allow everyone to have the most meaningful reduction in public health risk?

So, what does “meaningful” mean? Would meaningful be the same for a city in the East versus a city in the West? That’s where we need to carefully have discussions — about what provides the greatest good and about federal regulations that have extremely onerous or costly compliance requirements. What is the real benefit of a federal regulation for the entire country versus one that allows local decision-making?

Could this local approach be applied to PFAS as well?

For PFOA and PFAS, the reality is that we have seen a dramatic decline in general U.S. population exposure levels to those two chemicals, and that’s without a federal MCL. There are other tools in the toolbox that can be used.

We have great data from the CDC through a program that’s called NHANES — the National Health and Nutrition Examination Survey. It collects nationwide serum data for a whole host of chemicals, along with nutritional, dietary, and medical survey information. And what we’ve seen, since 1999, is more than an 85% reduction in PFOS and a 70% reduction in PFOA in the general population serum.2

To what do you attribute the drop in PFAS serum concentrations?

We’re just not being exposed to those chemicals through the same pathways anymore. We have cleanup actions, as well as response actions driven by litigation, throughout the U.S. And by phasing out manufacturing through the Toxic Substances Control Act (TSCA) — the EPA just announced, in January 2023, a proposed Significant New Use Rule for what it calls inactive perfluorinated compounds3 — we’re seeing dramatic exposure reduction, without an egregiously expensive MCL.

But a PFAS MCL is coming, set to be finalized by the end of 2023, so where do you see it landing?

I don’t have a crystal ball for the EPA’s regulations, but the final MCL will consider what can be done from a measuring perspective, a treatability perspective, and a cost perspective.

[Editor's Note: The EPA has since released proposed MCLs for PFAS.]

I do think it’s important to note that other agencies have looked at the same information and have come up with different interpretations of what is a reasonable limit. The World Health Organization (WHO), for example, released proposed guidance values for PFOA and PFOS, and they basically said the data are too uncertain to come up with numbers. They are proposing to set a “prudent level” — that was their term — based on the ability to detect, the ability to treat, and cost. They kind of took the health discussion off the table, which is really interesting for the WHO. It will be interesting to see where they land.

To sum up, what are the tenets for the risk-based approach to water regulations and policy that you advocate?

I think what’s important is that we understand that there are multiple risks facing our drinking water today — that nothing is as black and white as we would like for making decisions. We need to be prioritizing the multitude of risks, with consideration for the available funding and resources, and ask the hard questions:

Where does it make the most sense to spend our resources from a public health perspective?
Where are we going to most have the largest meaningful reduction in public health risk?