Microplastics, tiny plastic fragments less than five millimeters in size, are finding their way into everyday life. They appear in household dust, in food, and even in bottled water. It is not surprising that scientists have detected these particles in the stools of both humans and animals. Notably, researchers have observed that the stools of infants contain higher amounts of microplastics than those of adults living in the same area.
These microplastics have become a leading pollution issue caused by human activity and are dispersed globally. They are everywhere, and they show up in people as well. A striking finding is that babies may experience greater exposure to microplastics than adults, possibly because of certain daily items used during feeding and teething. These include feeding and drinking utensils, pacifiers, and plastic toys that infants chew on regularly.
This line of inquiry emerged from a study in Environmental Science & Technology Letters that examined exposure in infants and adults in New York. On average, the stool of a six-year-old child contained more microplastics than the feces of ten adults who shared the same environment. The measurement focused on two common types: polyethylene terephthalate PET, widely used in food packaging and textiles, and polycarbonate PC, found in toys and bottles. The researchers collected meconium from three newborns and stool samples from six one-year-olds and ten adults to compare concentrations across ages. Each sample contained at least one type of plastic, but the difference between adults and one-year-olds stood out most clearly. PET levels were significantly higher in the infants, while PC levels showed no significant age-related difference compared to adults. These results underline the unique exposure patterns present in early life.
Experts discuss several possible sources for these elevated concentrations. The utensils used during infancy meals, the fabrics babies are exposed to, and the habit of chewing on clothing or plastic items all contribute to the exposure picture. Studies have shown that baby food prepared in bottles can release microplastics, and many processed baby foods are packaged in plastic containers, which adds another route of exposure for one-year-olds. Additionally, textiles themselves can release PET microplastics, and infants frequently chew on fabrics, which increases exposure to microplastics found in textiles. The researchers emphasize the importance of further research with larger sample sizes to confirm and extend these initial findings. The study referenced here was conducted under the leadership of Kurunthachalam Kannan, a pediatrician at New York University, and was designed to assess exposure to the two prevalent plastic types PET and PC. The full citation for the work is 10.1021/acs.estlett.1c00559.