A study led by researchers from the University of New Mexico Health Sciences Center and published in Toxicological Sciences found nano- and microplastics (NMPs) in all 62 placenta samples they tested. Researchers identified the presence of rayon, polystyrene, polyethylene and other plastic particles. Polyethylene, which was present in 54 percent of the samples, is the most common plastic and is used in manufacturing water bottles, packing materials and bags. The research is important to evaluate the potential impacts of NMPs on adverse pregnancy outcomes.