Long ago, people chopped and minced meat and vegetables into natural surfaces such as rocks. In the end we decided to exchange these slabs for wooden cutting boards. More recently, many home cooks, restaurants and food manufacturers have switched to plastic boards for convenience, less weight and economy.
But recent research points to a potential downside: The cutting action of knives causes plastic boards to release tiny pieces called microplastics into the shredded food. Whether these plastic fragments affect health likely depends on many factors that continue to be studied.
Here's what researchers say about plastic boards and whether they should be replaced with another material.
What happens to the plastic on the cutting board?
New research shows that when people consume microplastics from various sources such as plastic water bottlesthey can be absorbed by body tissues. Some scientists believe this absorption may lead to chronic inflammation and oxidative stress, problems that increase the risk health problems.
However, some microplastics, including those from plastic cutting boards, may be too large for our bodies to absorb.
Research shows that when we cut plastic boards, microplastics are created and mixed with food. According to one source, one movement of a knife can remove 100-300 microplastic particles. analysis. Research shown that about 50% of the released microplastics remain on the cutting board after chopping and go down the drain when you wash the board (maybe good for you, but not so good for wastewater pollution). We consume the remaining 50%.
In 2023, a group of scientists from North Dakota State University found Microplastics got into the carrots after they were chopped on plastic boards. Based on their lab work, the team predicted significant exposure to microplastics from regular use of plastic boards over the course of a year. But they only looked for relatively large microplastics, says Said Iskander, assistant professor of environmental engineering and study author.
Read more: What happens to the plastic in dishwasher containers?
According to some studies, only the smallest microplastic particles can enter the body. liver cells and cause changes in the human body colon cells. In other documents there is suggested More generally, body organs can only metabolize microplastics smaller than 10 microns in size. (A micron is one thousandth of a millimeter.) Larger pieces can pass through the digestive tract harmlessly.
Iskander believes that if his team's methods allowed them to observe smaller microplastics, they would likely find a lot of them. In another studyResearchers in the United Arab Emirates examined microplastic contamination in raw fish and chicken on plastic cutting boards used by butchers. They only found particles measuring 15.6 microns or larger (although forced grinding by butchers can produce microplastics of different sizes than home-cooking).
“Size distribution is important when it comes to health because it really determines whether that material will just pass through the body or penetrate into it,” says Stephanie Wright, an associate professor at Imperial College London who studies microplastics and health. Wright adds that the microplastics found in the North Dakota and UAE studies are “generally considered too large to pass through the gut” to the rest of the body.
The UAE study also found that rinsing food after it has been shredded—for one minute with running tap water—removes small amounts of microplastics, but the vast majority stick to the food, said Thies Tiemann, study author and professor of chemistry at the United Arab Emirates University.
Research into particle size has not yet been completed. According to some researchLarger microplastic particles can pass through body barriers.
Microplastics can be dangerous regardless of size
Size may be just one factor in determining whether microplastics on cutting boards affect health. Some scientists say chemicals from microplastics can still cause problems even as the microplastics themselves pass through and out of the body.
Heat is studied as a factor. After the shredded food is mixed with microplastics, it is often thrown into the oven, stovetop or microwave. Since microplastics contain many chemical additives and have low melting point“They can break down and release these chemicals, especially if they are cooked at high temperatures,” explains Iskander. “The chemicals can easily enter our bloodstream.”
During frying or pressure cooking, “the heat will certainly cause the chemical additives to migrate out of the plastic,” Wright says. She adds that cooking oils and fatty meats further fuel this migration.
Read more: What happens to the plastic in disposable coffee capsules?
The same problem occurs the other way around, when food is cooked whole and then sliced and peeled while continuing to steam on plastic boards—a common practice in restaurants, Iskander notes.
Research has not directly linked the use of plastic cutting boards to human health effects, but they have been studied in animals. This year, Chinese scientists fed the mice a diet prepared on boards made of different types of plastic. Another group ate food cooked on wooden boards. After a few months, the group given the wooden board was doing well, but the mice given food cut on plastic boards had increased intestinal inflammation and disrupted gut bacteria.
This was confirmed even though no microplastics were found in the mice's bodies, suggesting that chemicals released by microplastics were to blame.
The authors emphasized that their findings do not apply directly to humans. They also noted that mice were deliberately injected with high doses of microplastics to simulate a year of exposure, but for a relatively short period of time. Lower doses should be studied in the future. “It's difficult to extrapolate from animal studies to much lower daily exposures,” says Wright, who was not involved in the study.
In our kitchens, exposure levels may vary depending on additional factors such as the vigor of chopping (harder foods require stronger knife strokes) and frequency of chopping. (Buying pre-made foods that have been highly processed to avoid grinding is not the solution; research is being done all the time. find Ultra-processed foods contain the most microplastics.)
Another issue is how long you have the board. Researchers in the UAE have found that plastic boards release more microplastics as they wear out with more intensive use. “Repetitive behavior and repeated exposure are probably quite important when we think about long-term health consequences,” Wright says.
Plastics and chemical additives used in cutting boards sold in the U.S. must meet U.S. Food and Drug Administration (FDA) safety requirements for “reasonable assurance of no harm,” says Kimberly Wise White, vice president of regulatory and scientific affairs for the American Chemistry Council, a trade association. “This means that [plastic] The polymer used to make the board must meet specifications, as do any additives,” says White.
US Department of Agriculture (USDA) advises on its website it says plastic cutting boards can be used “without health concerns.”
But microplastic research nascent. The World Health Organization is prioritization the need to address “known and foreseeable health risks.” European Food Safety Authority says more research is needed, in part because many studies are believed to overestimate the amount of microplastics due to erroneous measurements. “There is a lot of uncertainty,” says Iskander.
Alternatives to a cutting board
If you want to avoid plastic boards, wood is an alternative. However, the transition to wood goes both ways. It includes its own problems and concerns.
Wood is easier to cut with knives than another cutting board material, titanium, but there is a potential problem. microbial growth. Wooden boards have a porous surface that absorbs moisture and food debris, allowing bacteria to enter and multiply, which can lead to cross contamination.
Ben Chapman, chair of the Department of Agriculture and Public Health at North Carolina State University, whose podcast Risky or not? analyzes everyday risks associated with germs – believes there is little risk if boards are cleaned after each use. Any remaining bacteria “will probably die because they will get deep into the cracks,” he says.
Without such washing you could become one of 48 million cases foodborne illnesses annually in the United States. Just because you haven't gotten sick yet doesn't prove invincibility. “Acute disease risk is a game of probabilities,” Chapman says, depending on the type and timing of exposure.
Read more: 10 Ways to Gracefully Change the Subject
Plastic is superior to wood in terms of convenience, especially when it comes to cleanliness. The dishwasher will destroy wood planks, but plastic can be washed in the dishwasher. Wood should be washed by hand, first with soap to remove debris and then with a food-safe sanitizer, Chapman recommends. He uses a plastic board for raw meat and wooden boards for everything else.
Like plastic, wood planks need to be replaced every few years when they begin to fall apart or develop dark lines due to bacteria buildup, Chapman says. Increase their longevity by sanding away any biofilm lurking on the surface. Chapman sands his board from time to time to remove the top layer of funk.
Wood plank shed microparticles wood while cutting. However, Chapman notes that wood is “essentially plant-based,” so our digestive systems should have no problem processing these tiny pieces.
Another potential problem: Most cutting boards are made from many pieces of wood. Some adhesives may leach toxic compounds after some time. However, as with plastic boards, these additives must be approved by the FDA for food contact.
According to Tiemann, other (more expensive) versions are made from a single piece of wood. No microplastics, glue or mixed wood materials may mean fewer mixed feelings about your cutting board.
