Q&A: Award-winning scientist Anne Starling on the latest PFAS research— and where she finds hope

EHN senior news editor Brian Bienkowski saw down with Dr. Anne Starling, winner of the 2023 Lou Guillette Jr Outstanding Young Investigator Award, to discuss her work on PFAS and other toxics, how this has shaped her consumer habits, and where she finds hope.

The Lou Guillette Jr. Outstanding Young Investigator Award is an annual award given to an early career scientist who studies endocrine-disrupting chemicals — compounds like BPA and phthalates that alter the proper functioning of our hormones. Starling, an Assistant Professor in the Department of Epidemiology at the Gillings School of Global Public Health at the University of North Carolina, Chapel Hill and an adjunct Assistant Professor in the Department of Epidemiology at the Colorado School of Public Health, studies how chemical exposures, such as PFAS in drinking water, may increase the risk of chronic disease.

The award is conducted by HEEDS — a program within Environmental Health Sciences, which publishes EHN.org.

We talked to Starling about the award and her work. The interview has been lightly edited for brevity and clarity.

First off, congrats on the 2023 Lou Guillette Jr. Outstanding Young Investigator Award. Where in your academic and research journey did you start investigating endocrine-disrupting chemicals?

Thank you. I’m very honored by this award because I admire the work of HEEDS and also what I know of Dr. Guillette’s legacy as a scientist and a mentor. I’ve always been interested in environmental health, in how humans are influencing the natural environment, and how our own health may be affected by the way we construct and modify our environment. I began studying exposure to endocrine-disrupting chemicals when I was a graduate student in epidemiology at UNC Chapel Hill. I was fortunate to work with mentors both at UNC and at the National Institute of Environmental Health Sciences (NIEHS). At NIEHS, I worked with Dr. Jane Hoppin on the question of how exposure to agricultural pesticides may increase diabetes risk. Later, for my dissertation project, I worked with Dr. Stephanie Engel at UNC and Dr. Matthew Longnecker at NIEHS to investigate how exposure to certain persistent chemicals (per- and polyfluoroalkyl substances, or PFAS) during pregnancy can affect the health of the pregnant person and the outcome of the pregnancy.

What is something you’ve uncovered in your time investigating these harmful chemicals that most people would find surprising?

Many people that I talk to assume that chemical products that are widely used in the U.S. have gone through comprehensive safety testing, similar to what is required for prescription drugs and other medical treatments. But this is simply not the case. In our regulatory environment, the burden is on the regulators to demonstrate harm from exposure to chemicals, rather than a more precautionary approach. And it may surprise many people to know just how long it takes to accumulate enough scientific evidence to change policy. This is not necessarily due to any kind of conspiracy or political influence, but simply because science is slow, meticulous, and deliberate. It takes years to be confident that we have the right answers.

Some of your research has focused on PFAS in drinking water and its impact on developing fetuses. What have you found?

Yes, I’ve studied the effects of prenatal exposure to PFAS for several years now.There are now many studies that have reported that pregnant people with higher PFAS in their blood have babies that have, on average, somewhat lower weight at birth. This is concerning because we know that babies with low birth weight have a number of health challenges that may last throughout their lives. And even though the effects of PFAS exposure on birth weight may be small at the individual level, the impact could be large from a public health perspective because nearly everyone in the U.S. is exposed to these chemicals. My work has examined whether PFAS exposures at critical periods of development are linked with different patterns of child growth, that could potentially put them at greater risk of obesity, diabetes, and other chronic diseases. We’ve seen some evidence that exposures before birth may influence child growth, body weight and body composition (the amount of fat mass compared to lean body mass) through at least the age of school entry, and maybe longer.

When we think of pollution exposure, we often think of acute impacts, but that’s not always the case. What have you found when it comes to endocrine-disrupting chemicals’ ability to create long-lasting impacts to our health?

In general, we know a lot more about the acute effects of high doses of toxic chemicals than we know about the chronic or long-term effects of the low doses received daily by the general population. It’s challenging to study changes in people’s health related to exposures over many years, and that’s why epidemiology as a field is so interesting to me – we spend a lot of time thinking a bout how to overcome the challenges of observational research to draw valid and useful conclusions. When you don’t have a randomized controlled trial -which we almost never do in environmental health, for obvious ethical reasons –you have to be very strategic and rigorous in your study design to learn whether a certain exposure is actually causing harm.

Has doing this research changed how you act as a consumer? If it has, how so?

I think so. I am more wary of the chemical products that I bring into my home. I’m definitely a label-reader! But a major lesson that I have learned through this work is that we are not empowered as consumers to be able to avoid harmful chemicals in our daily lives. There are no ingredient labels on most of the products that we encounter every day, such as food packaging, clothing, furniture, and even the building materials and paint in our homes. It’s impossible for an individual to make well-informed decisions about all of these products. So rather than making recommendations about consumer choices, I advocate for policy changes to make sure that products that are known to be unsafe are not sold to consumers.

What research are you working on now that excites you?

In terms of impact, I’m excited to be contributing to a large, multi-site study of the health effects of PFAS exposure through drinking water, led by the Agency for Toxic Substances and Disease Registry. The study enrolled people from seven communities around the country, who all experienced high levels of PFAS in their drinking water at some point. I worked in one of these communities in Colorado for several years, and I have seen the level of worry and frustration that these contamination events can cause. It’s gratifying to be able to tell people who participated in these studies that we are now on the verge of having enforceable, national regulations on the maximum allowable amount of specific PFAS in drinking water. Scientifically, I’m also excited to be investigating other sensitive periods of exposure during the life course, beyond prenatal development. For example, puberty, pregnancy and menopause are dramatic periods of hormonal and physiological change, and they may also be critical windows during which exposure to endocrine-disrupting chemicals can cause lasting harm.

We are consistently hearing about the chemical exposures in our lives and it can be daunting. What gives you hope when it comes to these exposures and our health?

We are more educated than ever before about the trade-offs that we face in our industrial society. And we do make progress. Just think about how much healthier our children’s lives may be because they aren’t exposed to as much tobacco smoke or lead compared to previous generations. The science is moving at a remarkable pace, and we have to commit to adapting and changing as we learn more.