Biological Effects of Short, High-Level Exposure to Gases: Nitrogen Oxides.
Abstract
This report presents an analysis of the available literature describing the health and performance effects of exposure to nitrogen oxides (NOx). The US Army's concern is with high-level, short-term exposures that may exceed present threshold limit values of the American Conference of Governmental Industrial Hygienists: 5 ppm (9 mg/cum) as a TWA; intended changes are a TWA of 3 ppm (5.4 mg/cum) with a short term exposure limit of 5 ppm (9 mg/cum) for 15 minutes. Dose-response relationships were developed for intensities of exposure from the highest (fatal) level to thresholds of minimal response. It is concluded that NOx can in general be equated to nitrogen dioxide (NO2) because this is much more toxic than the only other oxide of importance, nitric oxide (NO), which oxidizes to NO2 in air. If NO is present in equal or greater concentration, an allowance for its effect is recommended. NO2 exhibits mainly two sets of toxicological characteristics: immediate irritancy and delayed, cumulative tissue damage. Proven effects are mainly on the respiratory tract. Intense exposures result in death, hospitalization with recovery, or severe responses not requiring hospitalization. Survivors may be free from permanent effects. This range covers concentrations from 20 ppm (38 mg/cum) to 200 ppm (376 mg/cum) and up, for single exposures of a few minutes up to 1 hour.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1980
- Accession Number
- ADA094502
Entities
People
- John D. Morton