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Resources Supporting ISA Development

Below is a list of commonly used resources that support the development of the integrated Science Assessments.

HERO Database

The Health Environmental Research Online (HERO) is a database of scientific studies and other references used to develop EPA's risk assessments, in this case the ISAs, aimed at understanding the health and environmental effects of pollutants and chemicals. HERO contains over 600 million citations from the most recently released ISA assessments including Lead, Ozone, and the Carbon Monoxide Assessment.

NAAQS Standards

The EPA maintains the National Ambient Air Quality Standards for pollutants considered harmful to public health and the environment. The Clean Air Act identifies two types of national ambient air quality standards. Primary standards provide public health protection, including protecting the health of "sensitive" populations such as asthmatics, children, and the elderly. Secondary standards provide public welfare protection, including protection against decreased visibility and damage to animals, crops, vegetation, and buildings. EPA has set National Ambient Air Quality Standards for six principal pollutants, which are called "criteria" pollutants. The NAAQS Standards therefore rely on the ISAs to get the best science for supporting the standards.

Report on the Environment

EPA's Report on the Environment (ROE) presents the best available indicators of national trends in the environment and human health. EPA selected these indicators to address 24 questions that are critical to EPA's mission of protecting the environment and human health. The trend data on the air questions that deal with air criteria pollutants show the questions EPA want to address.