It’s official: microplastics — tiny pieces of plastic measuring smaller than 5 millimeters — are inside us all, and they’re likely impacting our health.
These microplastics come from plastic debris that degrades into smaller and smaller pieces, and are now finding their way into our reproductive organs, hearts, livers, kidneys and even our bloodstreams.
That’s why one St. Mary’s University professor has set out to understand how these particles are reacting inside of us when they come across “everyday toxins” such as cleaning products, or chemicals found in the air we breathe or food we eat.
Earlier this summer, the university announced that the National Institutes of Health has awarded a four-year, $669,951 grant to Jennifer Harr, an associate professor of biological sciences at St. Mary’s, to research how microplastics exposed to environmental chemicals called “plasticizers” can damage the DNA, development and health in living organisms. Plasticizers are additives put into plastic to make it flexible.
Rather than test these effects on humans directly, Harr is performing her research by studying the effects within a much smaller lifeform — a microscopic roundworm called Caenorhabditis elegans or C. elegans for short. Along with a team of undergraduate students, Harr is studying if ingested microplastics absorb or carry toxins on their surfaces, and if so how they affect physiology and fertility.
“I’m learning a lot about these worms as I go,” said Chiara Maldonado, a junior at St. Mary’s and one of the students participating in Harr’s research. “I’m also learning a lot about the effects and differences between the worms when they’re exposed to the microplastics and when they’re not.”
The NIH grant is a big win for Harr and her students, Harr said, because it allows the students to be able to focus on the research as their job. Her students have also had the chance to present their research at a national conference and are adding real research work to their resumes.
“A big part of this mechanism is that it is meant for funding research in underserved institutes,” Harr said. “We’re 70% Hispanic serving, so we hit that.”
Harr said through the grant, she’s been able to hire on a full-time research assistant, St. Mary’s post-grad David Mares, 24, and several undergraduate students.
“It’s been really awesome having David, because it frees me up from doing some of the extensive experimentation prep work, which means I can work with the students more,” Harr said.
While humans are exposed to a baseline of toxins every day, there are normal levels of exposure that are safe, Harr explained. What is scary about microplastics is that they can absorb these toxins or carry them on their surface, essentially becoming a vehicle for these chemicals and having combined effects on our health that are currently unknown, she said.
Maldonado agreed.
“I think it’s more scary to think about how exposed we are, especially in our surroundings, our environment, all of the things that we touch and throw away, it’s adding to the issue,” she said. “It’s a very big issue that not a lot of people are talking about. I didn’t know anything about microplastics until I started this research, so I think it is very concerning.”
Harr said she and her students began receiving the funding last year, and will continue receiving it in allotments through 2027.
At the end of their research period, they plan to write a paper on the results that will be peer-reviewed and could potentially be published, Harr said.
