There have been a number of studies finding microplastics (tiny bits of plastic smaller than 5mm) in seafood, drinking water, many foods, as well as in the air we breathe (e.g. from the breakdown of vehicle tires and brakes during normal use). There has been some concern over what the microplastics are doing to us because so little research has been done. But there is worry that the smallest sized microplastics are entering our bodies, traveling to different organs, and causing damage. But at least some of the microplastics we ingest are traveling through the gastrointestinal system and then excreted in our stool, according to a recent study.
The study had 8 healthy volunteers from Europe and Asia (United Kingdom, Italy, Japan, Poland, Russia, Netherlands, Finland, and Austria). keep a food dairy for a week, and then "donate" a stool sample which was analyzed. None of the volunteers were vegetarians, and 6 had consumed fish from oceans in that week. [Note: Studies find that seafood contains microplastics.]
The stool samples were analyzed for 10 types of plastic. All the stool samples contained microplastics, with polypropylene and polyethylene terephthalate being the most abundant. The samples contained an average of 20 microplastic particles per 10 g of stool. Since 9 types of plastic was detected in the stool, the researchers say that means they come from multiple sources.
Recently Canadian researchers estimated that annual consumption of microplastics ranges from 39,000 to 52,000 particles (depending on age and sex). When they added in inhalation of microplastic particles, the numbers increased to 74,000 to 121,000. And those who only drink bottled water may be getting an additional 90,000 microplastics (versus about 4000 microplastics from tap water). Yikes!
What to do if this concerns you? Since plastic wrappers, containers, and bottles (including water bottles) shed microplastics, then one can try to purchase and store foods in plain cardboard or glass containers. Stainless steel containers are also OK (NOTE: aluminum cans are usually coated with suspect chemicals). Definitely drink more tap water, and less bottled water.