Reductions in NO2 and emergency room visits associated with California's goods movement policies: A quasi-experimental study

•This is the first study to assess the specific long-term and large-scale regulatory actions on air quality and health.•The California Goods Movement interventions was associated with substantial reductions in NO2 exposures.•The intervention also led to reductions in emergency room visits among Medicaid beneficiaries with respiratory diseases.•This paper contributed to scientific methods for assessing the health effects of regulatory actions.