Rochester researchers on the growing concern of plastics exposure on human health.
Plastic containers and utensils are staples in many kitchens-but could they be affecting your health?
Plastics, often seen as a single material, are actually made from many different polymers, each with a unique chemical makeup. They contain different chemical additives like dyes, plasticizers, and flame retardants. As these plastics interact with microbes and environmental chemicals, the risk to human health becomes more complex.
University of Rochester researchers are at the forefront of efforts to understand the complex role that plastics play in human health. They include Katrina Korfmacher, the codirector of the Lake Ontario MicroPlastics Center (LOMP) and a professor of environmental medicine, a collaboration between the University and Rochester Institute of Technology (RIT), and Jane van Dis, an assistant professor of obstetrics and gynecology at the Medical Center.
One of the most common ways people are exposed to plastics is in the kitchen:
- Black plastic spatulas and other utensils may contain harmful chemicals picked up when recycled from electronic waste.
- Plastic cutting boards shed tiny fragments of varying shapes and sizes that can be ingested.
- Plastic containers can leach chemicals when heated in the microwave.
What is black plastic, and why are there health concerns?
Black plastic is commonly used in kitchen utensils, takeout containers, food trays, and children's toys. But many of these products are made from recycled electronic waste, which can contain harmful chemicals like brominated flame retardants and heavy metals. These chemicals have been linked to a variety of health concerns, including:
- Cancer
- Endocrine disruption
- Neurotoxicity
- Infertility
A recent study found flame retardants in 85 percent of 203 tested consumer products, including banned chemicals, suggesting they were made from old electronic waste.
Are black plastics a risk to children?
Children are more vulnerable to environmental chemicals because their bodies and brains are still developing.
"Flame retardants have been detected in breast milk samples across the US. Children can also be exposed through contaminated food and house dust," says van Dis.
Some plastic toys contain flame retardants that may leach out when children chew on them, exposing children to chemicals that can affect brain and reproductive system development.
What are microplastics?
"Microplastics are any plastic particles that are less than five millimeters in size-and that's about the size of a tip of an eraser," Korfmacher says. Over time, large plastics-known as macroplastics-break down into microscopic fragments that move easily through the food chain and persist in the environment. Common sources of plastic pollution include food wrappers, plastic bottles, plastic bottle caps, plastic bags, plastic straws, cigarette butts, tire-wear particles, and synthetic clothing.
Plastic waste enters the environment via urban stormwater, agricultural runoff, and wastewater. Nurdles, or small plastic pellets often used to create plastic products, can also escape directly during the manufacturing process, Korfmacher adds. Microplastics have even been found in the air we breathe; when inhaled, they can lodge in the lungs or enter the bloodstream. In short, microplastics are ubiquitous, frequently difficult to detect and mitigate, and research has found the particles in human blood, heart, liver, and lung tissue, placenta, and breast milk. However, little is known about their long-term impact on human health.
"We're also studying much smaller particles called nanoplastics that are small enough that they can pass into the human body and even into human cells," adds Korfmacher. "So we're working hard to identify the kinds of plastics that actually get into our bodies, simulate those in the lab, and then use them in experiments." The goal? To ascertain how different kinds, shapes, sizes, and concentrations of plastics affect our health.
Are plastic cutting boards safe?
A recent study tried to mimic everyday exposure by feeding mice microplastics made by chopping on real plastic cutting boards. The results showed that different plastics caused different health effects: one type led to gut inflammation, while another changed the gut bacteria. This suggests that real-life plastic exposure is more complicated than lab studies conducted on single types of standard particles might suggest.
In an invited commentary on the study, the LOMP codirectors Korfmacher and Christy Tyler, a professor at RIT, reflected on how much plastic we might be adding to our food just by preparing meals at home using plastic tools and containers. They emphasized that while microplastic exposure is a growing concern, we still don't fully understand how it affects human health. For instance, although lab studies link microplastics to gut inflammation, only a small percentage of people have such symptoms.
How do I limit my exposure to plastics?
"The ways that flame retardants and other harmful chemicals end up in plastics we use on a daily basis are complex, as are the solutions," says Korfmacher.
Still, there are simple ways to reduce exposure:
- Choose wood or stainless steel utensils over plastic ones.
- Avoid microwaving food in plastic containers.
- Wash hands and wipe down surfaces after handling plastic packaging.
- Don't let young children chew on plastic toys.
"These substances are known endocrine disruptors, meaning they can interfere with hormonal systems and potentially lead to various health issues," van Dis says.
In the long run, they argue that better testing, safer alternatives, and preventing electronic waste from entering the production of consumer products-especially those that come in contact with food-need to occur to reduce sources of exposure.
