Harris County has joined a multi-state coalition pushing back against efforts by the U.S. Environmental Protection Agency to weaken federal air quality protections, underscoring the County’s ongoing commitment to safeguarding public health and defending science-based environmental regulations.

The coalition is opposing the EPA’s move to roll back strengthened National Ambient Air Quality Standards for particulate matter, known as PM NAAQS, which were updated just last year under the Federal Clean Air Act. The standards were revised after the agency’s own scientific findings concluded that fine particulate matter—particularly PM2.5—poses serious risks to human health, including increased rates of respiratory illness, cardiovascular disease, and premature death.

County officials argue that the EPA’s current position contradicts its own recent scientific assessments and would strip communities of critical protections. Harris County leaders have emphasized that weakening the standards would disproportionately harm vulnerable neighborhoods already burdened by industrial pollution and poor air quality, while ignoring established science meant to protect public health.

Harris County previously intervened in April 2024 in litigation initiated by the Texas Commission on Environmental Quality and Texas Attorney General Ken Paxton, which challenged the EPA’s updated particulate matter standards. At the time the rules were adopted, the EPA estimated that the strengthened protections could prevent as many as 4,500 premature deaths nationwide.

If the standards are overturned, the EPA would lose its authority to enforce limits on dangerous levels of particulate pollution and would no longer be able to require state agencies, including TCEQ, to address violations of federal air quality standards. County officials warn that such a shift would significantly weaken oversight and accountability, leaving communities with fewer tools to combat harmful pollution.

The coalition opposing the rollback includes more than 15 states, all urging the court to reject the EPA’s request and preserve the strengthened air quality standards. Harris County maintains that clean air protections are not only a regulatory obligation but a public health necessity, and that strong, enforceable standards are essential to ensuring residents can breathe clean, safe air.

The full court filing is available through CourtListener.