We live in an environment where plastic is in our clothing fibers, the air we breathe, the food we eat, the gum we chew, and the water we drink. Millions of plastic particles are ingested by people every year. What does that mean for our health and the environment?
As part of our ongoing Conversations in Cancer video series, Diane Reidy-Lagunes, MD, a medical oncologist at Duke Health, talks to Jason Somarelli, Ph.D., an assistant professor in medicine at the Duke University School of Medicine and a Duke Cancer Institute researcher who studies the effects of microplastics. Here, we cover the potential disease risks and what we can do to protect ourselves and future generations.
How large is the plastic problem?
Plastic may soon become the most ubiquitous human-made substance on the planet. If you look around your homes, your offices, you’ll see it’s everywhere. We’re ingesting upwards of millions of these particles every year.
Plastic production is on the rise. We’re not curbing the problem, we’re accelerating it. According to a 2025 report from the Pew Charitable Trusts, by the year 2040, the amount of plastic pollution in the environment will rise to the equivalent of dumping one garbage truck’s worth of plastic waste every second.
What do we mean when we say plastic?
Plastic is a catch-all term for polymers, the building blocks that form the solid matter, but it also includes the ten thousand added chemicals (additives)–such as dyes and chemicals that give plastics flame-retardant properties, for example–as well as things in the environment that latch onto the plastic.
What has research shown about the relationship between plastic and health?
Researchers are still trying to understand which plastic types and which chemicals from plastics are most harmful.
Studies have found plastic particles in every part of the body where they’ve looked, including tissues, blood, breast milk, placentas, the brain, and the heart. The amount of plastic in the heart has been correlated with heart attacks and other coronary events.
There’s also evidence of workplace exposure. Studies show people who work where plastic is manufactured have higher rates of many of these cancers.
A Duke study showed that levels of plastic in the brain have increased significantly since 2016, and this may correlate with dementia.
In animal studies, scientists are seeing a Parkinson’s-like disease and gut inflammation.
We need to reimagine how we’re using plastic and what goes into it because we didn’t know we would be eating so much of it.
What is known about the relationship between microplastics and cancer?
Studies in fish have shown ingestion of microplastics to cause inflammation, changes in their gut microbiomes, and an increase in liver cancers. But the problem is also with the additives–the chemicals in plastic. Our work at Duke found more than 150 known carcinogens in plastic. It’s not known if the doses of these additives we’re being exposed to every year are causing cancer, but it appears they may:
- Disrupt the hormone balance.
- Cause inflammation, an environment in which cancer can grow and thrive.
- Suppress immune function.
More research is needed.
We know there is an alarming rise In GI cancers in our young patient population. Is microplastic exposure increasing cancer risk in this population?
It hasn’t been proven, but we are seeing a rise in colorectal cancers at the same time that plastic production is rising. Every day, we are eating plastic, and the immune system is recognizing it as foreign and sending signals that are causing an inflammatory response. That becomes an environment in the gut for a cancer cell to start dividing. It may not be causing the cancer to originate, but it likely increases the risk for cancer to grow by creating the inflamed environment necessary for cancer to thrive.
Our team at Duke is working to find answers.
What is being done to understand whether plastic is causing problems or if it’s something else?
Our team at Duke is performing careful studies in the lab to disentangle the different variables–the type of plastic, the size limits, which polymers and which chemicals are most harmful, to understand what they do.
We’ve also formed the Duke Plastic Pollution Working Group, which is tackling this crisis from all facets of society, from research to policy and community action. Our work includes partnerships with governmental agencies to change policies and community groups, so everyone is involved in understanding and learning how to combat this problem.
What can people do to lower their personal exposure to microplastics?
It’s nearly impossible to avoid plastic altogether, but there are small steps you can take to reduce how much plastic you ingest.
- Become informed. That’s the goal of this conversation.
- Take small steps to eliminate plastic in your home and environment.
- Don’t drink from plastic bottles and avoid plastic cooking utensils.
- Choose safer alternatives like silicone, which is a plastic but doesn’t degrade into microplastics.
- Use glass storage containers and cutting boards.
- Choose paper over plastic shopping bags or use reusable bags.
- Google “plastic-free” to find companies that offer plastic-free products.
- If you choose to use plastic, reuse and recycle to avoid creating more garbage.
As consumers, we have collective power. We should try to use our power to encourage companies to produce materials that are safe and sustainable.
Does it matter what we do if there is no way to escape plastics that are everywhere?
Ingesting plastic does not mean you will have heart disease, dementia or cancer, but it increases your risk. Taking steps to reduce the amount of plastic you ingest and in your environment can make a difference.
Similarly, small steps can make a big difference in reducing plastic pollution in the environment and making the world a safer place for future generations.
