US EPA

4795759 

Journal Article 

Immediately Dangerous to Life or Health (IDLH) Value Profile: Acetonitrile (CAS No. 75-05-8) 

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

2017 

Overview of the IDLH Value for Acetonitrile IDLH value: 137 ppm (230 mg/m3). Basis for IDLH value: The mouse LC50 value of 2,693 ppm for a 60 minute exposure to acetonitrile [Willhite 1981] was selected as the basis for the IDLH value. Duration adjustment resulted in the calculation of a 30-minute equivalent LC50 value of 4,120 ppm. A composite uncertainty factor of 30 was applied to account for extrapolation from a concentration that is lethal to animals, animal to human differences, and human variability, resulting in an IDLH value for acetonitrile of 137 ppm. 1.2 Purpose: This IDLH Value Profile presents (1) a brief summary of technical data associated with acute inhalation exposures to acetonitrile and (2) the rationale behind the immediately dangerous to life or health (IDLH) value for acetonitrile. 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 acetonitrile, the in-depth literature search was conducted through July 2017.