NCJ Number
190893
Date Published
1999
Length
13 pages
Annotation
This document provides a health risk assessment of the chemical warfare agent sulfur mustard.
Abstract
Sulfur mustard is classified as a vesicating agent because of its ability to cause blisters on exposed skin. Sulfur mustard is the chemical warfare agent present at most stockpile and nonstockpile munition sites in the United States and its territories. At the request of the Army, Oak Ridge National Laboratory (ORNL) conducted a health risk assessment of sulfur mustard. The assessment included a detailed analysis of its physical and chemical properties, environmental fate, toxicokinetics, mechanism of action, animal and human toxicity, and carcinogenicity. On the basis of that assessment, ORNL proposed a reference dose (RfD) of a number of milligrams/kilograms of body weight per day for noncancer health effects and a slope factor (SF) of 9.5 mg/kg per day for the carcinogenic potency of sulfur mustard. The Army’s Surgeon General accepted ORNL’s proposed RfD and SF as interim exposure values until an independent evaluation of the proposed RfD and SF was conducted by the National Research Council. It was concluded that the approach used by ORNL to calculate the interim RfD for sulfur mustard is consistent with the guidelines of the Environmental Protection Agency. On the basis of available toxicity and related data on sulfur mustard, it was concluded that the Army’s RfD was scientifically valid, although it is believed that slightly different uncertainty factors should be used. The approach selected by ORNL to calculate the SF was scientifically valid given the absence of epidemiological or animal carcinogenicity studies of sulfur mustard. Using an updated estimate, the Army’s interim SF should be lowered to 1.6 per mg/kg per day. 2 tables and 17 references