The average American kitchen is full of objects that release microplastics into food and drinks, whether through plastic cutting boards or the lining of teabags.
Microplastics, or fragments of any plastic that measure less than five millimeters in length, lurk in oceans, the air, food, and even drinking water.
Humans constantly inhale and ingest them, raising the odds of experiencing whole-body inflammation, neurological effects, DNA damage, and a weakened immune response.
Microplastics differ from PFAS, ‘forever chemicals’ derived from plastic, which can take years to degrade in the environment and the human body. Microplastics are nearly as ubiquitous and take hundreds of years to break down in the environment.
Now, a growing body of evidence has shed light on the everyday items in your kitchen that are likely to contain the most microplastics.
Researchers in Pakistan found that each cup of tea brewed using a plastic tea bag released approximately 11.6 billion microplastics and 3.1 billion nanoplastics
Experts also recommend reaching for plastic-free glass or bamboo cutting boards, as plastic cutting boards also leach microplastics into food
Worldwide, people consume an average of five grams of microplastic every week, depending on age and sex, studies suggest.
Many plastics are used worldwide, with more than 20 percent classified by the EU as concerning due to their persistence, accumulation in human tissues, or toxicity.
The next time you make a cup of tea, consider that most tea bags are made with unsustainable polypropylene plastic and are not biodegradable. In some cases, excluding the tea, plastic accounts for roughly 25 percent of the teabag.
Not only are teabags an environmental hazard, but according to 2023 research from the Dow University of Health Sciences in Pakistan, when combined with hot water, they release a flood of microplastics.
Researchers there found that each cup of tea brewed using a plastic tea bag released approximately 11.6 billion microplastics and 3.1 billion nanoplastics.
Tea bags may also contain other harmful substances, including fluorine compounds, arsenic, radium salts, aluminum, copper, lead, mercury, cadmium, barium, and nitrates.
Even paper tea bags may release microplastics from the sealant to close the bags.
Paper cups that hold the tea and other hot drinks also release microplastics. While they may seem like a suitable alternative to plastic and styrofoam cups, paper cups are not harmless.
The inside of the cups is lined with a sealant, typically up to 10 percent high-density polyethylene (HDPE), to insulate them and prevent leakage.
A disposable paper cup (100 ml) with a plastic liner can leach approximately 25,000 micron‐sized microplastic particles in the hot liquid it holds.
Toxic heavy metals such as lead (Pb), chromium (Cr), and cadmium (Cd) were also found in the films used in tea bags, and there is concern that these metals can leach into hot water during brewing.
Like plastic lining on paper cups, plastic ice cube trays can also impart microplastics to ice.
Plastics, being resistant to water and ice, tend to float on the surface of water and ice. When water freezes, these plastic particles are pushed out of the ice because they don’t mix well with water.
As more people become aware of the dangers of microplastics in the home, new, plastic-free alternatives have emerged.
Silicone and metal ice trays are promoted as a sustainable alternative to plastic trays.
Plastic food storage deemed microwave-safe also leaches microplastics into the food it holds.
In 2023, a team of researchers from the University of Nebraska-Lincoln found that microwaving baby food in plastic containers can release more than two billion nanoplastics and four million microplastics per square centimeter of the container.
The health issues associated with consuming microplastics are still under investigation. Still, one of the team’s experiments concluded that three-quarters of cultured kidney cells were dead just two days after being in contact with the particles.
The researchers concluded that toddlers consuming microwaved dairy products and infants drinking microwaved water/drinking products absorb the ‘greatest’ relative concentrations of plastic.
Experts also recommend reaching for plastic-free glass or bamboo cutting boards, as plastic cutting boards also leach microplastics into food.
A 2023 peer-reviewed study reported that chopping on polypropylene cutting boards released more microplastics (5-60 percent greater mass and 14-71 percent greater number of microplastics) than polyethylene boards.
Using a polyethylene cutting board could result in an annual exposure of seven to about 51 grams of microplastics per person, whereas a polypropylene board could lead to an exposure of 49.5 grams.
In terms of quantity, polyethylene boards may release between 14.5 to about 72 million microplastics annually, while polypropylene boards could release nearly 80 million.
Microplastics are nearly impossible to avoid as they touch every facet of our lives. Because of this, a growing body of research is examining how they might effect human health.
Eleven brands of bottled water collected from around the world, for instance, were tested for microplastics, and 93 percent showed signs of contamination.
What’s more, as study of human placentas published earlier this year found evidence of microplastics in every single sample, with concentrations ranging from 6.5 to 790 micrograms per gram of tissue.
PVC and nylon were the most common plastics detected, after polyethylene.
Plastics contain thousands of chemicals, including human carcinogens, endocrine disruptors, neurotoxicants, and persistent organic pollutants.
When microplastics enter the body, they are seen as foreign invaders, triggering an immune response similar to fighting off a virus or bacteria.
But, unlike viruses or bacteria, the body can’t break down microplastics, leading to persistent inflammation. This chronic inflammation is a significant concern because it’s linked to diseases like diabetes, cardiovascular issues, and cancer, which are leading causes of death.