Infants have more microplastics in their feces than adults

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. In cells and laboratory animals, microplastic exposure can cause cell death, inflammation and metabolic disorders. Kurunthachalam Kannan at the New York University School of Medicine and colleagues wanted to assess human exposure to 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 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. However, they note that larger studies are needed to corroborate these findings.