Indoor air quality and heart health

A 2025 study found that using a high-efficiency particulate air (HEPA) filter to trap tiny particle pollutants may help lower blood pressure for people living near busy roads. Of particular concern are particles less than 2.5 microns in diameter, known as PM_2.5, which creates inflammation that damages blood vessels and contributes to high blood pressure. Nearly a quarter of Americans live near vehicle-congested roads, and many more people are exposed to pollution from wildfire smoke.