This section provides information on hazardous chemicals and their characteristics which can be used to inform various aspects of the planning and decision process described in Section 2 above. Hazardous chemicals include chemical warfare agents (CWAs), toxic industrial chemicals (TICs), and other compounds such as some types of drugs and pharmaceuticals. Some TICs can also be classified as CWAs (e.g., hydrogen cyanide and phosgene). Cleaning up hazardous chemical incidents effectively requires a clear understanding of their toxicity, key physical and chemical properties, sources of exposure, routes of exposure, the persistence of the chemical hazards and reactivity with other substances, as well as the prevailing environmental conditions and characteristics of the materials and surfaces impacted by the specific hazardous chemical incident.
Previously, the development and testing of CWAs was focused on their battlefield effects. This resulted in well-documented data as to the concentrations required to cause injury and death to unprotected individuals. More recently, agencies of the federal government (such as the Department of Defense [DOD], Centers for Disease Control and Prevention [CDC], and EPA) have initiated research programs to obtain toxicological information on low-level exposure to CWAs.29 While these studies are providing much- needed information regarding the effects of low-level and long-term exposures, definitive results for all CWAs are not available at this time.