Improving human health through environmental monitoring and stewardship

By Pete Zrioka

For World Pollution Day Dec. 2, we spoke with Rolf Halden about his research and the Biodesign Center for Environmental Health Engineering that he has directed since opening the center in 2012.  

Creating the first open access dashboard for wastewater-informed public health monitoring of opioid use and COVID-19 infections is just one of the many accomplishments of the Biodesign Center for Environmental Health Engineering at Arizona State University. 

Under the leadership of director Rolf Halden, the center has produced numerous discoveries to improve human health through environmental stewardship — and in some cases, spurred federal action. 

With a focus on population health assessment and management, research from the center has led to a U.S. Food and Drug Administration ban on some harmful antimicrobials, uncovered common pesticides and perfluorinated chemicals — commonly known as “forever chemicals” — in umbilical cord blood and advanced human health protection with new technologies for wastewater and groundwater monitoring.  

Halden credits the success of the center to his team: virologist and bioinformatician Matthew Scotch, risk assessment expert Kerry Hamilton and Assistant Research Scientist Erin Driver, who has touched nearly every project at the center. Scotch is an associate dean and professor in the College of Health Solutions and Hamilton is an associate professor in the School of Sustainable Engineering and the Built Environment.  

Together, they work on regional, global and national scales to manage and understand the key determinants of human health and global sustainability.  

In this Q&A, Halden reflects on his research, its impact, and the tension between privacy and research. Answers are edited for length and clarity.  

Question: Why is this work important to society?  

Answer: Health protection is cheaper than treating the exposed and diseased. Our center works to identify health threats before they can develop into epidemics and pandemics, whether from biological agents such as SARS-CoV-2 or Mpox, or chemical agents like the so-called forever chemicals, opioids, antimicrobials and toxic building materials.  

Q: What is the biggest challenge in this field of research? 

A: Balancing the right for privacy of individuals and subpopulations with the need to perform public health assessments to protect at-risk populations is a great challenge.  

There’s a lot of information that is collected on all of us all the time, and it is often used and monetized. Oftentimes, we don't know that information is collected, and we are not the beneficiaries of the information we contribute. So, this is a question of equity and fairness, and data can be very powerful. Our society hasn’t quite developed an ethical framework around this collection of information, including information obtained by monitoring domestic sewage. 

Wastewater monitoring is the process of analyzing wastewater for biological surveillance. When we did this in Tempe, we held town hall meetings with stakeholders before the monitoring even began. This is one of the few times when people were informed on what was going on. They had a voice and could contribute their ideas.  

In the absence of regulatory guidance, we must be our own stewards, which is a little like the fox guarding the chicken coop. And with any emerging technology, the researchers studying them typically know the most about the technology, but they're not ethicists by training. Some say it's not our job. Yet, if we create a new technology, we researchers are in a unique position to voice potential concerns early on, to inform a discussion of ethical and delicate questions. As an example, in 2021 my colleagues and I published an article on the ethics of and privacy concerns surrounding wastewater monitoring, to stimulate a discussion that hopefully leads to some insights and action. 

Q: What is something you consider one of the center’s biggest successes?  

A: Some of our notable work includes the discovery of triclocarban and triclosan as national priority pollutants, the subsequent call for regulatory action via a congressional briefing in Washington D.C., and finally the ban of triclocarban, triclosan and 17 other antimicrobials by the U.S. Food and Drug Administration in 2017. Our research — dating back to 2004 — was foundational to this ban. 

Q: How are students involved in the center’s research? 

A: At all levels — from volunteers to undergraduate and graduate — students are driving and partaking in research, discovery and technology transfer. They do everything from coming up with ideas, brokering agreements, to inventorying the data and starting new businesses licensed from ASU intellectual property.  

We’ve had people that are interested in a field that is not necessarily our cup of tea, who have managed to integrate their field of interest into our research program and then using it as the nucleus for their honor theses.  

For example, while diet and health are not our specialty area, it turns out that if you look at wastewater, you understand exactly what people eat and where they're deficient. We also had a student who worked on stress hormones early on and others researched opioid abuse, healthy diets, meat consumption, and caffeine as a marker to estimate the size of populations represented in wastewater samples.  

Q: What is an example of nature-inspired research at your center? 

A: To create safe chemicals, we need to design a chemistry that is compatible with ecosystems and human health. There are some principal design lessons that still need to be implemented, such as stopping the mass production of forever chemicals including poly- and perfluorinated organic compounds. Chemical design needs to include an end-of-life strategy; cradle to cradle rather than cradle to grave (landfill). 

Q: How did you become interested in science, and in particular, the field you are in?  

A: As a biologist, I developed an appreciation for the complexity and beauty of nature and my cross-training in engineering allowed me to apply tools and design principles to protect both human health and the ecosystems humanity relies on for survival. 

Q: What key events set you on your research path? 

A: My first job was in environmental remediation. I decided to move into biological design to prevent pollution from occurring in the first place. 

There's plenty of work to do in cleanup, right? We are constantly creating a mess. My first job was at the Lawrence Livermore National Lab cleaning up one of the priority sites in the country. But it became quickly apparent that while we are kind of janitors mopping up, the spills continue left and right. So I asked myself, “How can we be more impactful rather than just dealing with the consequences?” That led to me first to Johns Hopkins University, where I started the Center for Water Health, and later to ASU. 

Q: Describe your experience with Biodesign’s collaborative, interdisciplinary research culture. 

A: Nothing that we’ve accomplished at the center would be possible without the approach of housing multiple disciplines under one roof. I think this has encouraged encounters and

 collaborations that wouldn’t have happened otherwise. One example is the work that we do with Stephanie Forrest, the director of the Biodesign Center for Biocomputing, Security and Society. She approached us and together we started to investigate the privacy concerns of wastewater monitoring. 

Now we're working on a way of data sharing that allows for the extraction of health information without sharing that information between different competing entities. For example, if you have multiple hospitals, they don't want to share their statistics because that can inform competitors. But obviously hospitals have a lot of important information. Some of the cities might have an interest in understanding what their challenges are with drugs, or alcohol consumption, nicotine consumption, but they don't necessarily want to vent their affairs out to the other communities that might then stigmatize them. And so, there's computational ways of taking in the information and then analyzing it and bringing it back to customers, but not allowing direct flow from one entity to the other, so that everyone can protect their interests, while maximizing public health.