Background: Air pollution is a major environmental hazard to human health and a leading cause of morbidity for asthma worldwide. Objectives: To assess the current evidence on short-term effects (from several hours to 7 days) of exposure to ozone (O3), nitrogen dioxide (NO2), and sulfur dioxide (SO2) on asthma exacerbations, defined as emergency room visits (ERVs) and hospital admissions (HAs). Met...

Assessing whether long-term exposure to air pollution increases the severity of COVID-19 health outcomes, including death, is an important public health objective. Limitations in COVID-19 data availability and quality remain obstacles to conducting conclusive studies on this topic. At present, publicly available COVID-19 outcome data for representative populations are available only as area-level ...

Ground level ozone is a highly reactive, oxidative gas commonly found in urban and suburban environments, mostly derived from anthropogenic emissions. Numerous epidemiological studies and several reviews from health and environmental agencies worldwide have reported that exposure to this pollutant is associated with adverse health outcomes, including increased short term mortality and morbidity. E...

The Integrated Science Assessment for Sulfur Oxides – Health Criteria is a concise synthesis and evaluation of the most policy-relevant science, and has been prepared as part of the review of the primary (health-based) National Ambient Air Quality Standards (NAAQS) for Sulfur Oxides (SOx)under the Clean Air Act. The SOx ISA, in conjunction with additional technical and policy assessments, provides...

This final report provides the U.S. EPA’s evaluation and synthesis of the most policy-relevant science related to the health effects of gaseous oxides of nitrogen. It provides a critical part of the scientific foundation for the U.S. EPA’s decision regarding the adequacy of the current primary (health-based) national ambient air quality standards for nitrogen dioxide....

The Integrated Science Assessment for Ozone and Related Photochemical Oxidants is a concise synthesis and evaluation of the most policy-relevant science, and has been prepared as part of the review of the primary (health-based) and secondary (welfare-based) National Ambient Air Quality Standards (NAAQS) for Ozone and Related Photochemical Oxidants under the Clean Air Act. Welfare effects are non-h...

The Integrated Science Assessment (ISA) for Particulate Matter is a concise synthesis and evaluation of the most policy-relevant science, and has been prepared as part of the review of the primary (health-based) and secondary (welfare-based) National Ambient Air Quality Standards (NAAQS) for Particulate Matter (PM) under the Clean Air Act. Welfare effects are non-health effects which, according to...

Lead is one of six principal (or “criteria”) pollutants for which EPA has established NAAQS. EPA periodically reviews the scientific basis for these standards by preparing an ISA. The external review draft of the Pb ISA was reviewed by the Clean Air Scientific Advisory Committee (CASAC), an independent science advisory committee mandated by Section 109 (d) (2) of the Clean Air Act (CAA). The 2024 ...

This report is EPA’s latest evaluation of the scientific literature on the potential human health and welfare effects associated with ambient exposures to CO. The development of this document is part of the Agency's periodic review of the national ambient air quality standards (NAAQS) for CO. The recently completed CO ISA and supplementary annexes, in conjunction with additional technical and poli...

Air pollution is a leading cause of mortality and morbidity worldwide. Short-term exposure (from one hour to days) to selected air pollutants has been associated with human mortality. This systematic review was conducted to analyse the evidence on the effects of short-term exposure to particulate matter with aerodynamic diameters less or equal than 10 and 2.5 µm (PM10, PM2.5), nitrogen dioxide (NO...