One of Robert F. Kennedy Jr.’s first campaign promises during his failed presidential bid was to curb plastic pollution, partly because of the dangers of microplastics to human health. Fast forward several months, and Kennedy is now Health and Human Services Secretary, charged with making America healthy again, but has not yet used his new power to address the microplastics problem.

Although microplastics have been on the radar of environmental advocates such as Kennedy for decades, biomedical research is relatively new on how these ubiquitous nanoparticles from degrading plastics affect human health. So far, microplastics have been linked to several health problems, ranging from infertility to cancer to antibiotic resistance, and are becoming a new source of urgent concern for public health researchers.