Per- and polyfluoroalkyl substances (PFAS), or forever chemicals, are being identified in more places. Period products are on that list, likely because of the resistance to stains and liquids conferred by these chemicals. Building on previously presented research, a team publishing in ACS’ Environmental Science & Technology Letters found that some reusable products, namely period underwear and reusable pads, contained PFAS, which might be absorbed into the body through skin contact.

In early 2025, wildfires spread in Los Angeles, destroying tens of thousands of homes and businesses. During the fires, smoke blanketed the region and online maps provided residents with rapid air quality information. Now, a study in ACS’ Environmental Science & Technology Letters compares the data that went into the maps from federal monitoring stations, low-cost sensors and satellites. Their results highlight the importance of combining multiple data sources to form easily accessible information for the public.

As a chronic condition, rheumatoid arthritis (RA) can’t be cured, so treatment focuses on managing the disease and controlling its progression. Although current treatments help control RA symptoms in most people, they cannot prevent the onset of RA or painful flare-ups. Now, researchers publishing in ACS Central Science have developed nanoparticles that could slow disease progression and reduce flare severity, based on results from tests with human blood and mice models with RA-like disease.