US EPA

The present Supplement to the Second Addendum (1986) to the document Air Quality Criteria for Particulate Matter and Sulfur Oxides (1982) focuses on evaluation of newly available controlled human exposure studies of acute (a\1h) sulfur dioxide (SO2) exposure effects on pulmonary function and respiratory symptoms in asthmatic subjects.

The Supplement more specifically: (1) incorporates by reference and concisely summarizes the most important key findings on the same topic from the previous criteria reviews in the 1982 Criteria Document and its 1986 Second Addendum, as they pertain to derivation of health criteria for a possible new acute exposure primary sulfur dioxide National Ambient Air Quality Standard (NAAQS); and (2) provides an updated assessment of new information that has become available since completion of the 1986 Second Addendum and is of likely importance for derivation of health criteria for any such short-term sulfur dioxide effects, but rather is targeted explicitly on those human studies thought to provide key information useful to U.S. EPA decision making.

NCEA is undertaking to update and revise, where appropriate, the air quality criteria for sulfur oxides (SOx), last addressed in this document. Interested parties are invited to assist the EPA in developing and refining the scientific information base for updating the Air Quality Criteria for Sulfur Oxides (SOx) by submitting research studies that have been published, accepted for publication, or presented at a public scientific meeting.

U.S. EPA. Supplement to the Second Addendum (1986) to Air Quality Criteria for Particulate Matter and Sulfur Oxides (1982): Assessment of New Findings on Sulfur Dioxide and Acute Exposure Health Effects in Asthmatic Individuals (1994). U.S. Environmental Protection Agency, Washington, DC, EPA 600/FP-93/002, 1994.