By Eva Briggs, MD
Would you eat a credit card worth of plastic? No? Actually, the average person may be consuming 5 grams of microplastic every week.
That’s the amount found in a credit card.
The plastics industry began in the 1950s. Now plastics are found in all manner of products. Of the 8.3 billion tons of plastic produced since then, almost 80% is now in landfills or contaminating the natural environment.
Much of that plastic breaks down into microparticles, 0.001 to 5 millimeters in size, or nano particles less that 0.001 millimeter in diameter. These microplastics are found in the water and soil, and many are eventually taken up by organisms feeding in the water or growing in the soil.
This is a pathway for microplastics to make it into our food supply.
They’ve been found deep in the ocean, in Antarctic ice, in shellfish, table salt, drinking water and beer. When hot liquid is placed in a plastic food container, it sheds microplastics. For example, if parents shake hot formula in a plastic baby bottle, their child might consume more than one million microplastic particles every day. Microplastics are even drifting in the air we breathe.
Because microplastics can be detected in soil and sediments, where they will become incorporated in the rocks and fossils of the future, scientists have proposed naming the current era the plasticene.
What exactly is in those microplastics? A whole host of chemicals. Some derive from the plastic itself: reinforcing fillers, plasticizers to increase moldability, antioxidants and UV stabilizers to prevent damage from sunlight and environmental stressors, lubricants, dyes, flame retardants and more. And some substances are absorbed from the surrounding environment.
What is all this plastic doing to our health?
That’s still a big unknown. It’s difficult to know because microplastics have so many different shapes, sizes and chemical composition. We do know that certain plastics are harmful, for example, BPA. This chemical enables plastic to survive high heat (as in a microwave) and to withstand high speed collisions. These properties are valuable for food packaging. But alas, BPA is a hormone disrupter. It increases the risk for obesity, heart disease, reproductive disorders and breast cancer. It is not banned in food containers, but you can by BPA-free reusable
water bottles.
Phthalates are another group of potentially harmful substances used to enhance plasticity, flexibility and elasticity. They are colorless and odorless. But they also are endocrine disrupters that can interfere with human and animal reproduction or possibly cause cancer. Eight phthalate chemicals are banned in children’s toys and child-care items. However, they are still allowed in other vinyl plastic items and adult personal care items.
Most worrisome are nanoplastic particles. They may be able to get inside of individual cells. Their tiny size makes them difficult to detect and measure.
Human studies of the effect of most microplastics are lacking. We aren’t yet sure whether they harm via irritation, or via chemical effects on metabolism, or by accumulating in our tissues.
Whatever the effects on human health may be, it will likely become worse over time as more plastics accumulate in our environment. But plastic pollution can be reduced by reusing items when feasible, switching to alternative materials and beefing up plastic recycling.
Measures that you can take include avoiding single-use plastic water bottles. Drinking filtered tap water cuts the amount of ingested plastic particles in half compared to bottled water. Microwave your food in a ceramic container rather than plastic. Synthetic fibers release plastic nanoparticles when washed, so switch when possible to natural fibers such as wool, silk, cotton, and hemp. Avoid plastic packaging in food and other purchases when possible.
Eva Briggs is a retired medical doctor who practiced in Central New York for several decades. She lives in Marcellus.