Occurrence of Polyethylene Terephthalate and Polycarbonate Microplastics in Infant and Adult Feces

Although human exposure to microplastics (MPs) and the health effects thereof are a global concern, little is known about the magnitude of exposure. In this study, we quantitatively determined the concentrations of polyethylene terephthalate (PET) and polycarbonate (PC) MPs in three meconium and six infant and 10 adult feces samples collected from New York State. PET and PC MPs were found in some meconium samples (at concentration ranges from below the limit of quantification [<LOQ] to 12,000 and <LOQ–110 ng/g dry weight, respectively) and all infant stool specimens (PET: 5700–82,000 ng/g, median, 36,000 ng/g; PC: 49–2100 ng/g, median, 78 ng/g). They were also found in most (PET) or all (PC) adult stool samples but at concentrations an order of magnitude lower than in infants for PET MPs (<LOQ–16,000 ng/g, median, 2600 ng/g). The estimated mean daily exposures from the diet of infants to PET and PC MPs were 83,000 and 860 ng/kg body weight per day, respectively, which were significantly higher than those of adults (PET: 5800 ng/kg-bw/day; PC: 200 ng/kg-bw/d). Our study suggests that infants are exposed to higher levels of MPs than adults.