The snap of a coffee lid, the pop of a chip bag opening, the crinkle of an empty wrapper – all ways that we use plastic before discarding and forgetting about it.
But we’re reminded of the pollution problems from plastic when it breaks down into smaller and smaller pieces. These microplastics are now a problem for humans and the environment on a massive scale, since more than 8.3 billion metric tons of plastic have been produced since the 1950s.
Amid this problem, California’s Department of Toxic Substances Control is proposing to add microplastics to its Safer Consumer Products Candidate Chemicals List, which identifies substances with a “hazard trait and/or an environmental or toxicological endpoint.” If finalized, the state would consider microplastics harmful to humans, animals and the environment.
EWG submitted comments in July supporting the proposed addition of microplastics to this list. This addition is an important step towards protecting Californians, children and ecosystems from microplastic exposure and the chemical additives frequently used in plastics.
What are microplastics?
Smaller than a pencil-top eraser, microplastics are plastic particles under 5 millimeters in size, and nanoplastics are under 0.001 millimeters in size.
They can be categorized by shape: beads are spherical; fibers are thread-like pieces; films are thin, flexible pieces like food wrappers; and fragments are irregularly shaped, mostly broken off from larger pieces of plastic. Sunlight and microbes fracture plastics into smaller pieces that easily enter the environment.
California defines microplastics in drinking water as “solid polymeric materials to which chemical additives or other substances may have been added, which are particles that have at least three dimensions that are greater than 1 nanometer and less than 5 millimeters.”
Microplastics come from the widespread, global use of plastic and the resulting pollution. Some microplastics start out small, such as resin pellets, abrasives and microbeads. Microbeads are banned in “rinse off” personal care products – think soap and facial cleansers – but are still allowed in other applications. Most microplastics that pollute the environment arise from the weathering of larger plastics.
The U.S. generates the largest amount of plastic waste in the world – 42 million metric tons in 2016 alone – through illegal dumping of waste and shipping plastic waste to other countries. This number is expected to grow without extraordinary international measures to reduce and clean up plastic waste.
Where are microplastics found?
In humans
Scientists are just beginning to understand the potentially harmful health effects in humans from exposure to microplastics. Microplastics have been found in human lungs, blood, organs and even in the placenta.
Humans consume microplastics through the food we eat, the water we drink, the air we breathe and the things we touch. An average person absorbs an estimated 39,000 to 52,000 microplastic particles a year with food and drink. The number of inhaled microplastic particles is estimated to be between 35,000 and 69,000 particles in a year.
Microplastics have been found in our food and drink, from beer and sugar to chicken and milk. Seafood is a large source of microplastics in our diets. Most microplastics are located in the digestive tracts of fish that are thrown out before being prepared as food. However, seafood that’s eaten whole, such as anchovies, shrimp or mussels, accumulate microplastics in their bodies that end up in humans after consumption.
In the environment
With roughly 60 percent of plastic produced still accumulating in landfills and the environment, it’s no wonder that it has been found in the most remote corners of the world. Microplastics are found in freshwater systems, on land, in the deepest ocean basins and in arctic sea ice.
Reports of marine animal deaths from microplastic ingestion first appeared in the late 1960s when seabirds had stomachs full of plastic rather than food. Microplastics impact animals not only on an individual level, but laboratory experiments have demonstrated the toxic effects of microplastics all the way down to the cellular and molecular levels.
Are microplastics toxic?
Numerous research studies show microplastic toxicity to animals and the environment. But growing evidence points to a public safety concern for microplastics in humans.
Microplastics are difficult to study in people because of their small size and the complexity of researching interactions within the human body. Scientists are still learning how microplastics may negatively impact human health, even though microplastics are already found in human tissue.
Microplastics’ ability to break down into nanoplastics means many are already the same size as other disease-causing pathogens in humans such as viruses or parasites. Microplastics are not biologically active like these pathogens, but the smaller the size, the easier they are absorbed into the body and cells.
Additionally, manufacturers make plastics with different types of additives and chemicals, such as phthalates. Continuous exposure builds up levels of microplastics in the body which release additives over time, potentially harming human health.
When plastic breaks down in the environment, it can absorb a range of chemical pollutants, or microorganisms that pose additional health risks. If these contaminants enter the human body, they have the potential to harm our health in many ways.
Prolonged periods of exposure to airborne microplastics could lead to respiratory problems and increase the risk of cancer. Scientists in South Korea reviewed research on the human toxicity of microplastics and found potential adverse human health effects. Microplastic shapes can interfere with the digestive and respiratory systems, and their chemical additives and contaminants could harm the endocrine and reproductive systems.
How to minimize microplastic exposure
Microplastics are unavoidable given the many ways that we use and are exposed to plastic in our daily routines. But there are some things you can do to reduce your exposure and, in turn, help lower the amount of plastic that gets released into the environment. Some tips:
- Say no to single-use plastic and choose reusable containers and bags. Replace a plastic water bottle with a stainless steel one and plastic kitchenware with wood, glass or metal.
- Microwave food in glass containers. Heating food in plastic containers can release millions of microplastic particles into your food.
- Filter your drinking water. Home water filters can be effective at removing some microplastics and other contaminants.
- Dust and vacuum regularly. Removing excess dust from your home can cut down exposure to plastic fibers in dust.
- Support plastic pollution policies and legislation. Addressing plastic pollution requires institutional change and coordination of governments to reduce single-use plastic.
