US EPA

4795768 

Journal Article 

Immediately Dangerous to Life or Health (IDLH) Value Profile: Nitrogen Dioxide (CAS No. 10102-44-0) 

Dotson, GS; Maier, A; Parker, A; Haber, L 

2017 

Overview of the IDLH Value for Nitrogen Dioxide IDLH value: 13 ppm (24 mg/m3). Basis for IDLH value: The IDLH value for nitrogen dioxide is based on a LOAEL of 30 ppm for respiratory irritation and severe cough in volunteers following a 70 minute exposure [Henschler et al. 1960]. Duration adjustment resulted in the calculation of a 30-minute equivalent LOAEL of 38 ppm. A composite uncertainty factor of 3 was applied to account for human variability yielding an IDLH value 13 ppm for nitrogen dioxide. 1.2 Purpose This IDLH Value Profile presents (1) a brief summary of technical data associated with acute inhalation exposures to nitrogen dioxide and (2) the rationale behind the immediately dangerous to life or health (IDLH) value for nitrogen dioxide. IDLH values are developed on the basis of scientific rationale and logic outlined in the NIOSH Current Intelligence Bulletin (CIB) 66: Derivation of Immediately Dangerous to Life or Health (IDLH) Values [NIOSH 2013]. As described in CIB 66, NIOSH performs in-depth literature searches to ensure that all relevant data from human and animal studies with acute exposures to the substance are identified. Information included in CIB 66 on the literature search includes pertinent databases, key terms, and guides for evaluating data quality and relevance for the establishment of an IDLH value. The information that is identified in the in-depth literature search is evaluated with general considerations that include description of studies (i.e., species, study protocol, exposure concentration and duration), health endpoint evaluated, and critical effect levels (e.g., NOAELs, LOAELs, and LC50 values). For nitrogen dioxide, the in-depth literature search was conducted through July 2017.