Note: This web page is a part of DTSC's Hazardous Waste Classification training course.
Toxic Wastes
The dictionary defines toxic as something that is capable of causing injury or damage to a living organism. For toxicity, once it has been determined how much of a hazardous substance the waste contains, the concentrations are compared to applicable state and federal waste chemical lists and hazardous waste thresholds. If the waste contains or exceeds the regulatory threshold of the toxic substance, then the waste is a toxic hazardous waste1.
Some chemicals have a specific Regulatory Threshold (RT). When laboratory results indicate that the concentration equals or exceeds the RT, the waste is toxic and hazardous.
Chemical in waste: 40 ppm
Regulatory Threshold: 10 ppm
Waste = Toxic Hazardous Waste
A waste may be identified as a toxic hazardous waste through a number of pathways that involve laboratory testing, including:
- Total analysis
- Toxicity Characteristic Leaching Procedure (TCLP), a federal test
- Waste Extraction Test (WET), a California test
Total analysis measures the total concentration of a chemical present in the waste; the results are reported in chemical mass per waste mass (e.g., milligrams of chemical/kilogram of waste).
TCLP and WET methods are designed to show how chemicals behave in a landfill setting through laboratory simulations. California uses the WET method and Federal agencies use the TCLP method.
References
1 22 CCR Section 66261.24