Testosterone and estrogen differentially regulate human CD4⁺ T-cell responses during gender-affirming hormone therapy

Summary

This study examined dose-dependent effects of polystyrene nanoplastics on human bronchial cells, providing direct evidence of respiratory tract toxicity from inhaled nanoplastic particles. Airborne microplastic and nanoplastic exposure through inhalation is an emerging human health concern, and characterizing dose-response relationships in bronchial tissue is essential for establishing safe exposure thresholds and informing regulatory limits on airborne plastic pollution.