Characteristic Hazardous Wastes

Ignitable wastes (40 CFR Part 261.21) readily catch fire; are spontaneously combustible; or have a flash point below 140°F (60°C), i.e., the vapor above a pool of liquid will catch fire under a standard set of conditions.^1,2,9 Other ignitable wastes include non-liquids that burn under specific conditions (e.g., friction or water absorption), and certain compressed gases and strong oxidizers. Ignitable wastes (D001) in oral healthcare facilities include alcohol and silver nitrate.

Corrosive wastes (40 CFR Part 261.22) are acids and bases (pH equal to or less than 2 or a pH equal to or greater than 12.5), which can readily dissolve flesh or corrode metal and other materials such as storage tanks, drums, and barrels.^1,2,9 Sulfuric acid from automotive batteries is among the most common hazardous corrosive wastes. Examples of corrosive wastes (D002) that may be found in oral healthcare facilities include acetic acid and sodium hydroxide.

Reactive wastes (40 CFR Part 261.23) readily explode (e.g., discarded munitions) or may undergo violent reactions under normal handling conditions.^1,2,9 Other reactive wastes explode or violently react when exposed to heat or water; or generate toxic fumes, gases, or vapors or explosive mixtures when exposed to water.^1,2,9 Lithium-sulfur batteries that may be found in oral healthcare facilities are considered reactive wastes (D003).

Toxic wastes (40 CFR Part 261.24) leaching into groundwater drinking supplies from wastes disposed of in landfills is one of the most common ways the general population can be exposed to hazardous chemicals found in industrial waste.^1,2,6,9 Some toxic wastes generated in oral healthcare facilities may contain lead (D008), mercury (D009), and silver (D011), which are regulated at levels of 5.0 mg/L, 0.2 mg/L and 5.0 mg/L, respectively.