The Integrated Risk Information System (IRIS) is an EPA database created in 1985 that provides independent, science-based assessments of the health risks posed by chemicals. IRIS scientists quantify the highest safe level of exposure to a chemical before it causes health effects, including cancer. Federal and state regulators, courts, and public health agencies rely on IRIS assessments to set limits for chemicals in air, water, and soil. With more than 500 chemical assessments in its library, IRIS has underpinned hundreds of environmental regulations for four decades.