Microplastics (tiny plastic pieces less than 5 mm in size) are everywhere these days, from indoor dust, to food, to bottled water. Scientists have also detected these plastic particles in the feces of people and pets. Now, the results of a small pilot study have revealed that infants have higher amounts of one type of microplastic in their stool than adults. The health effects of these microplastics in human digestive tract are uncertain.
Little is known about the magnitude of human exposure to microplastics or their health effects. Although microplastics were once thought to pass harmlessly through the gastrointestinal tract and exit the body, recent studies suggest that the tiniest pieces can cross cell membranes and enter the circulation. Similar to the scientific findings on nanoparticles (like Titanium dioxide or “white food coloring”) used in food and meds, in cells and laboratory animals, microplastic exposure can cause cell death, inflammation and metabolic disorders.
Scientists focused on studying the effects of two common microplastics — polyethylene terephthalate (PET) and polycarbonate (PC) — by measuring levels in infant and adult feces. The researchers used mass spectrometry to determine the concentrations of PET and PC microplastics in six infant and 10 adult feces samples collected from New York state, as well as in three samples of meconium (a newborn infant’s first stool). All samples contained at least one type of microplastic. Although average levels of fecal PC microplastics were similar between adults and infants, infant stool contained, on average, more than 10 times higher PET microplastic concentrations than that of adults. Infants could be exposed to higher levels of microplastics through their extensive use of products such as bottles, teethers and toys, the researchers say. Larger studies are needed to corroborate these findings.
Journal Reference: Junjie Zhang, Lei Wang, Leonardo Trasande, Kurunthachalam Kannan. Occurrence of Polyethylene Terephthalate and Polycarbonate Microplastics in Infant and Adult Feces. Environmental Science & Technology Letters, 2021; DOI: 10.1021/acs.estlett.1c00559