Oral Exposure to Nylon-11 and Polystyrene Nanoplastics During Early-Life in Rats

A critical knowledge gap currently exists regarding the potential risks of exposure to nanoplastics (NPs), particularly early in life during key stages of growth and development. Globally abundant plastics, polyamide (nylon) and polystyrene (PS), exist in various products and have been detected in food and beverages as small-scale plastics. In this study, we evaluated how early-life exposure to NPs affects key biological metrics in rat pups. Male and female animals received an oral dose (20 mg/kg/day) of nylon-11 NPs (114 ± 2 nm) or PS NPs (85 ± 1 nm) between postnatal day (PND) 7 and 10. The results showed slight differences in the ratio of liver weight to body weight for male rat pups exposed to PS NPs. Cardiac performance and levels of neurotransmitters and related metabolites in brain tissue showed no differences between animals exposed to NPs and controls. The endogenous metabolite profile in plasma was altered by oral administration of NPs, suggesting perturbation of metabolic pathways involved in amino acid and lipid metabolism. This study explored the biological impacts of oral NP exposure early in life, supporting the need for continued investigations into the potential health effects from exposure to NPs.