Harvard Horizons Scholar Looks to ‘Sound the Alarm’ on ‘Forever Chemicals’


Heidi M. Pickard, a fifth-year Ph.D. student in Engineering and Applied Sciences at the Harvard Graduate School of Arts and Sciences, used her 2024 Harvard Horizons project to investigate environmental contamination and human exposure to highly prevalent “forever chemicals.”

Pickard is one of eight Harvard Horizons Scholars for 2024, a cohort of “outstanding” Ph.D. students at Harvard selected to present their research to a wider audience.

Her research centers around measuring the prevalence of per- and polyfluoroalkyl substances — known as PFAS or “forever chemicals” due to their inability to be digested within human bodies — throughout the Northeast, specifically in a variety of Cape Cod fish species.

In an interview, Pickard said she uses “a toolbox of methods to investigate the full extent of PFAS contamination.”


“Is it our drinking water? Is it from the products we use? Is it from the seafood we eat?” she said.

Current research has linked high levels of PFAS to decreased fertility and high blood pressure in pregnant women, developmental effects in children, reduced immune system capability, and increased risk of cancer and obesity.

In the fall of 2022, the City of Cambridge briefly switched water sources due to a spike in PFAS contamination.

Pickard said the “scale” of PFAS contamination originally inspired her to investigate the set of chemicals.

“There was this class of synthetic chemicals that are literally used in everything, basically all of our consumer products and all of these industries,” Pickard said. “They’ve been around since the 1930s. There is all this toxicity data associated with them.”

“You can find them everywhere in the world,” she added. “They were in the high Arctic, you can find them in the entire Antarctic, in the islands and the ocean and basically every animal on the planet.”

Pickard said she wants to spread information about PFAS chemicals and their dangers, adding that public awareness of the chemicals has risen in recent years.

When she was first researching the chemicals, Pickard said, “I would say maybe 30 percent of the people I had talked to had even heard of PFAS.”

“Now fast forward nine years later, a majority of people that I have talked to have now heard of PFAS. They’re really prevalent in the media,” she added. “There’s a lot going on in terms of regulations and lawsuits, but they’re still produced and used in many of our products.”

Pickard said the fish she has researched are a primary food source for local communities, especially the Mashpee Wampanoag tribe, creating a sense of urgency to understand the impacts of PFAS contamination.

“We don’t have a great understanding of those chemicals also being taken up into the fish and shellfish that are being consumed,” she said.

In her presentation, she wrote that she hopes her research spurs action on the issue.

“My work is trying to sound the alarm,” she wrote.

Pickard will present her research alongside her fellow Horizon scholars at the Harvard Horizons Symposium in Sanders Theater on April 9.

—Staff writer Adina R. Lippman can be reached at

—Staff writer Angelina J. Parker can be reached at Follow her on X @angelinajparker.