Yesterday, I cleaned out my vegetable drawer and made a stir fry for dinner. I chopped garlic, ginger, carrots, onion, peppers, broccoli, cauliflower, zucchini, spinach, celery, and scallions. It was a lot of chopping—512 chops to be exact.
I counted because of a new study from North Dakota State University. It made me uneasy about using plastic cutting boards.
The study showed that if I had used a plastic cutting board instead of my bamboo one, I would have made between 1,536 and 7,680 tiny plastic pieces. These would stick to the board, my knife, and even my veggies. Not very appetizing.
I usually use plastic cutting boards, so this study got me concerned. I decided to talk to the main researcher to understand more.
Bye-bye to my clearly deteriorated plastic cutting boards. See all those cut marks? That plastic is likely inside me and my family. (Photo: Kristin Hostetter)
Himani Yadav is a student doing her third year of advanced studies (doctoral) at North Dakota State University. She also works as a research assistant and helps in teaching.
During her master’s degree, she was curious about how we come into contact with tiny bits of plastic called microplastics in our daily lives. She focused on finding these microplastics in cooked food.
We come across microplastics all the time in our day-to-day activities. Studies have shown that it’s present in things like bottled water, seafood, and even the air we breathe. When we put plastic containers in the microwave, tiny bits of plastic can mix with our food.
One of her teachers suggested looking at how plastic cutting boards release these tiny bits of plastic. This idea sparked her curiosity. She says, “We decided to start with a small study, and as we looked deeper, we realized this could be a significant investigation.
It could help us understand more about how we are exposed to microplastics, something not many people think about. Once plastic is made, it doesn’t really disappear. Even if we recycle or reuse it, it breaks down into smaller pieces that end up inside our bodies.
Inside the Plastic Cutting-Board Test
In the Plastic Cutting-Board Test, Himani Yadav wanted to see how plastic cutting boards release tiny plastic particles during chopping. She knew that people have different ways of chopping, so she asked five people to help with the tests.
They got 20 cutting boards from Amazon for the experiment. Yadav got plastic cutting boards made of polyethylene and polypropylene, and she got wooden ones for comparison.
There were three parts to the test. First, they mimicked chopping 500 times on the polyethylene board without using anything. In the second part, they used polypropylene boards instead of polyethylene to compare how each material reacted.
The polypropylene boards released a bit more microplastics, but the difference wasn’t big. In the third part, they chopped carrots on the polyethylene boards, as Yadav found that many people use this kind of cutting board.
After they finished chopping, Yadav washed the carrots and boards in really clean water. Then, she poured this water through a special filter that can catch really tiny things.
After that, she looked at the filter under a microscope and counted and weighed all the little plastic pieces it caught.
Should You Be Worried About Microplastics?
Have you ever noticed those tiny marks on your old plastic cutting board? If you touch them, you can feel the surface isn’t smooth anymore. Each mark means the plastic is slowly breaking down. But where does that plastic go? I never thought it could end up in my stir-fry.
“We think that from a polyethylene cutting board, you get around 1 to 14 tiny plastic pieces with each cut, and from a polypropylene board, it’s about 3 to 15 pieces,” explains Yadav. “Our study assumes an average person makes 500 cuts daily on a board.
So in a year, that’s 128,000 cuts. Adding up those numbers, the microplastics we might be exposed to range from 7.4 to 50.7 grams per year.”
To put it in perspective, a plastic credit card weighs about five grams. So, at the highest end of this estimate, it’s like having 10 credit cards’ worth of plastic shed onto your board and food each year.
Now, the big question is: Is it harmful to consume these tiny bits of plastic? We don’t have a definite answer yet. Yadav’s study did an early test on mouse cells (not on people) to check how it might affect our bodies.
Time to Retire Plastic Cutting Boards
We didn’t find any immediate harm from polyethylene on mouse cells,” Yadav mentions. “But our testing in this area was just a beginning and not very detailed.” Normally, tests for toxicity only last for 24 or 72 hours, so it wasn’t surprising that they didn’t observe any instant effects in the mouse cells.
“In the future, we plan to delve deeper into toxicity studies because there’s a lot of existing research on this matter,” she explains. “We’re aware that microplastics enter our intestines and bloodstream, causing harm. They can trigger the production of endocrine disruptors linked to various cancers and reproductive system issues.
” Simply put, it doesn’t seem beneficial for us. Yadav’s perspective is clear: “Even if we can’t see the immediate effects of microplastics, they will likely have long-term effects as they accumulate in our bodies and tissues.”
Personally, I’ve removed plastic cutting boards from my kitchen. They’re now in my garden shed as I consider what to do with them. Perhaps one day, I’ll repurpose them creatively.
However, one thing I won’t do is put them in my regular recycling bin without confirming with the facility, as most won’t accept them. Instead, I’m considering a nice wooden cutting board, maybe even putting it on my Christmas wish list. Or better yet, I might try making one myself.