Acutely and Extremely Hazardous Wastes

Acutely and extremely hazardous wastes are wastes that would cause death, disabling personal injury, or serious illness. These wastes are more hazardous than ordinary hazardous wastes.

Acutely hazardous wastes are listed as “P” wastes in the federal system. The main difference between P listed wastes and other federally regulated hazardous wastes is the criterion used to identify acutely hazardous chemicals. The criteria:

• Separates highly toxic (acutely hazardous) waste from other toxic wastes (U listed wastes)
• Establishes the management method for containers that held P listed wastes

In the California, we have identified extremely hazardous wastes with an asterisk in Appendix X. Identifying whether a hazardous waste is an extremely hazardous waste has a bearing on authorization under the tiered permitting system. A hazardous waste is extremely hazardous based on the following criteria:

• Acute oral toxicity – LD₅₀ is less than 50 mg/kg.
• Acute dermal toxicity – LD₅₀ is less than 43 mg/kg.
• Acute inhalation toxicity – The LC₅₀ is less than 100 ppm.
• Carcinogenicity – Single or combined concentration equal to or exceeds 0.1 percent (1000 ppm).
• Experience or testing – Like hazardous waste criteria, these wastes are shown through experience or testing to pose an extreme hazard.
• Water reactivity – When contacted by water, the waste reacts violently, generating extreme heat, burning, exploding or having some other rapid reaction.
• Persistent and bioaccumulative toxic substances: