Microplastics research needs ironing out
“Last month, Briefing readers recoiled from the news that human brains seem to be full of plastic bits — with a recent study of autopsied bodies finding our brains might contain as much as 4.5 bottle caps’ worth of plastic. But some of the most shocking studies about microplastics in human tissues rely on small sample sizes, lack appropriate controls or “are not biologically plausible”, write four health researchers. “Without more rigorous standards, transparency and collaboration — among researchers, policymakers and industrial stakeholders — a cycle of misinformation and ineffective regulation could undermine efforts to protect both human health and the environment,” they argue.” Nature Briefing, 10 March 2025

Nature Medicine, 3 February 2025

Bioaccumulation of microplastics in decedent human brains

Rising global concentrations of environmental microplastics and nanoplastics (MNPs) drive concerns for human exposure and health outcomes.

Complementary methods for the robust detection of tissue MNPs, including pyrolysis gas chromatography–mass spectrometry, attenuated total reflectance–Fourier transform infrared spectroscopy and electron microscopy with energy-dispersive spectroscopy, confirm the presence of MNPs in human kidney, liver and brain. MNPs in these organs primarily consist of polyethylene, with lesser but significant concentrations of other polymers. Brain tissues harbor higher proportions of polyethylene compared to the composition of the plastics in liver or kidney, and electron microscopy verified the nature of the isolated brain MNPs, which present largely as nanoscale shard-like fragments.