Tiny pieces of plastic are polluting some of Lancaster County’s most well-known waterways, where local researchers fear they could pose threats to both human health and wildlife.
In fact, the plastics — some made with harmful chemicals — have been found in more than 50 major rivers, streams and lakes across Pennsylvania.
“They are so ubiquitous, they are everywhere now,” said David Bowne, an associate professor of ecology at Elizabethtown College.
Bowne was talking about microplastics — plastic fragments smaller than 5 millimeters that are often created when larger pieces of pollution break down over time.
He shared his thoughts in the days before officials at the PennEnvironment Research & Policy Center revealed on Wednesday that microplastics were present in Lancaster County. Specifically, they have been identified in water samples taken from the Conestoga River, the Little Conestoga Creek and Eshleman and Millers runs.
Those waterways were included in a PennEnvironment project that searched for the pollutants in 53 Pennsylvania waterbodies, including some that feed drinking water systems and others that serve as popular recreation sites.
According to the published results, microplastics were found in every case. The study simply looked for the presence of plastics in those waterways, not for concentrations, said Faran Savitz, a PennEnvironment conservation associate.
And there is no doubt that the pollutants are much more widespread, having been found in rainwater, dust in the air and on remote mountaintops, he said Wednesday.
“There is nothing right now that is effective to get microplastics out of our environment,” he said.
In the local waterways, researchers collected multiple samples from January to June of last year, searching for four different kinds of microplastics: fibers, which are shed from synthetic clothing and other textiles; fragments, which break off from hard-plastic litter; film, which comes from flexible plastic like bags; and beads, which are used in cosmetic products like face scrubs.
“We found microplastics in 100% of our samples,” researchers said, noting that was true even in apparently “pristine” locations, where larger, traditional litter wasn’t visible.
Won’t go away
“Plastic doesn’t biodegrade,” Savitz said. “Instead, they just break into smaller and smaller pieces of plastic.”
And those small pieces aren’t simply floating downstream. They’re making their way inside of the creatures that live in rivers and streams, according to John Wallace, director of Millersville University’s Center for Environmental Sciences.
Wallace, an entomology professor, said he’s aware of that because he’s part of a group preparing to soon publish results of a separate multiyear study searching for microplastics in freshwater insects.
Unlike the PennEnvironment study, Wallace’s work didn’t include Lancaster County waterways. Instead, it focused solely on the neighboring Schuylkill River watershed.
There, scientists at Stroud Water Research Center in Chester County have collected aquatic insects — including mayflies and caddisflies — for decades, archiving specimens, Wallace said.
For their research, Wallace and a team of students looked at the archived insects, focusing on a period of about two decades ending in 2019. Spanning urban, agricultural and forested habitats, the study also examined the insects at different developmental stages — larva, pupa and adult.
Infiltrating the food chain
While Wallace could not share all the findings discovered during the not-yet-published project, he revealed that plastics were found within the insects, even at their youngest stages. And in some habitats, their presence has increased since 2010.
The presence of microplastic inside living creatures might be alarming on its own, Wallace said.
But on top of that, some types of plastic are made with substances called endocrine-disrupting chemicals, which can interrupt hormonal activity.
Insects with plastic inside of them are eaten by larger bugs and other river-dwellers like crayfish and fish, Wallace said. Some fly away from water when they reach their adult forms, making their way to land, where they are consumed by birds and other land animals, he said.
“These insects are all food for predators,” Wallace said,
Additional research is needed to see exactly how the chemicals’ effects might spread up the food chain, he said, but some studies have already shown that endocrine-disrupting chemicals adversely impact fish, disrupting development and reproduction.
Humans — including trout-eating anglers — are at the top of that chain, Wallace pointed out. And during a Wednesday presentation, Savitz said statistics show that people consume about a credit card worth of plastic each week.
“This is really quite alarming,” Wallace said.
Bowne, of Elizabethtown College, agreed, pointing out that some plastics are made up of known cancer-causing materials. The small microplastics also have been known to draw in and carry other toxic pollutants already present in environments.
And he guessed that microplastic pollution isn’t only present in water, but also on land. There, it could be picked up by plants, including those consumed by livestock — providing yet another entry point into the food chain, Bowne said.
“It could very well ... be a source of soil contamination,” he said, blaming plastic consumer goods for much of the problem.
“It is kind of another manifestation of our obsession with plastics,” Bowne said before acknowledging that people are becoming more conscientious with their buying habits. “I think more and more of the general population is becoming aware of microplastics, but unfortunately, we don’t know what the consequences are.”
Present in human bodies
For Alan Peterson, a retired Lancaster County physician, those potential consequences are of concern, especially because microplastics also have been identified inside human bodies.
Even more alarming, Peterson said, is recent research that found the plastics inside of placentas attached to developing babies.
“That was sort of an eye-opener to a lot of folks when they saw that in the literature,” said Peterson, who has long studied the relationship between health and the environment.
Like Wallace, Peterson noted the plastics’ hormone-disrupting effects while also raising concerns about how the chemical-laden substances could impact fetal development, possibly interrupting receptors that link mothers to their unborn children.
Obviously, he said, additional studies are needed to understand the full scope of microplastics’ impact on human health, but in Peterson’s mind, actions need to be taken to prevent this type of pollution.
“If we ever needed a reason to try to get plastics out of our environment … these early studies, I think, can give us trepidation, to say the least,” Peterson said. “We need to do better as humans with our environment and this is just one example.”
Fundamental changes needed
It’s that type of action that the PennEnvironment researchers have called for.
Alongside their reported findings, they’ve made a number of environment-focused policy suggestions, including the banning of single-use plastic bags.
“We need to fundamentally change the way that society produces and markets products that consumers buy,” Savitz said. “We need to change the ways in which we deal with waste in order to tackle this form of pollution, and we need to make the creators of this environmental hazard start to take responsibility for the products that they put in the marketplace.”