The USEPA identifies two broad categories of hazardous waste, which in turn are each further divided into four sub-categories:
1. Listed hazardous waste (40 CFR 261, Subpart D).
- Non-specific sources (F-codes).
- Specific sources (K-codes).
- Discarded commercial chemical products, off-specification species, container residues, and spill residues thereof (P-codes & U-codes).
2. Characteristic hazardous waste (40 CFR 261, Subpart C).
- Ignitability (D001).
- Corrosivity (D002).
- Reactivity (D003).
- Toxicity (D004 – D043).
For the Federal regulations of the USEPA and those of most states with an authorized hazardous waste program, those identified above are the only hazardous waste subject to “cradle to grave” regulation under Subtitle C of RCRA. Some states, however, have exercised their authority to create their own state-specific hazardous waste; an example of this is Minnesota which created two additional characteristic hazardous wastes in addition to the four Federal characteristic hazardous wastes it also recognizes:
- Oxidizer (D001)
- Lethality (MN01)
This article will summarize the Minnesota-specific hazardous waste characteristic for Lethality. Readers requiring more information than provided in this article should refer to a guidance document provided by the Minnesota Pollution Control Agency (MPCA): The Lethality Characteristic – A Minnesota-specific hazardous waste characteristic.
Note the following:
- While your state may have a state-specific hazardous waste characteristic similar to Minnesota’s Lethality, don’t confuse this hazardous waste with those of your state. Refer to your state environmental agency for guidance.
- Knowledge of this hazardous waste characteristic is necessary not only to hazardous waste generators in Minnesota, but also any out-of-state generator who may send their waste to Minnesota for treatment, storage, or disposal.
- If not a Lethal hazardous waste, a waste may be hazardous for other reasons. Conversely, a waste may exhibit the characteristic of Lethality, while also meeting the definition of a listed or other characteristic hazardous waste.
First of all, don’t confuse the Minnesota-specific Lethality characteristic with the USEPA & MPCA regulated Toxicity characteristic. The Toxicity characteristic is determined by the presence of certain toxic chemicals in a leachable form above specified concentrations. It is usually determined by a test method known as TCLP – the Toxicity Characteristic Leachate Procedure – though an alternative method (cheaper and faster) is acceptable. The Lethality characteristic is based on the toxicological or poisonous characteristics exhibited by a waste as determined by biological testing or other sources of information about the waste.
Under MPCA rules, a waste is hazardous for the characteristic of Lethality if a representative sample exhibits any of the following:
- An oral LD50 (rat) <500 mg/kg.
- A dermal LD50 (rabbit) <1,000 mg/kg.
- An inhalation LC50 (rat) <2,000 mg/m3 for dusts and mists.
- An inhalation LC50 (rat) <1,000 ppm for gases and vapors.
Evaluating for Lethality:
Determining if your waste exhibits a characteristic of Lethality can be achieved by several methods, one of which is to determine if the product from which the waste is generated displays any of a list of attributes complied by the MPCA:
- A drug regulated by the Minnesota Board of Pharmacy.
- A pesticide regulated by the Minnesota Department of Agriculture.
- A poisonous material regulated for transport by the U.S. Department of Transportation.
- A material bearing any of the descriptive or signal terms “Poison”, “Poisonous”, ”Toxic”, “Lethal”, “Fatal” or “Deadly” on the product shipping container, product label, or in product documentation.
- A material bearing the ‘skull and crossbones’ graphic on the product shipping container, product label, or in product documentation.
- A material bearing a U.S. Department of Transportation “Hazard Class 6.1” label or placard on the product shipping container, product label, or in product documentation.
- A material bearing a National Fire Rating (NFR), Hazardous Materials Identification System (HMIS), or Hazardous Material Identification/Information Guide (HMIG) rating Health Division ≥3 or Special Hazard Division “POI” NFR only) label on the product shipping container, product label, or in product documentation
- A material bearing LD50 data on a Material Safety Data Sheet (MSDS) which you have, or which you are required by OSHA regulations to have, which states that the LD50 of any of the ingredients is less than the lethality thresholds documented earlier in this article.
- A material having specific information known to you that the waste may reasonably be Lethal, including but not limited to information that your processes may alter a product or other material which does not exhibit any of the above attributes in such a way that the waste generated may reasonably be considered Lethal.
- A material having specific information published by the MPCA (documented later in this article) that the waste may reasonably be considered Lethal.
Wastes which display no attributes may be considered non-Lethal. Wastes which display one or more attributes may be Lethal and must be evaluated further. Further evaluation may take the form of calculating the LD50 of the waste, or applying knowledge of the materials and processes used in generating the waste.
Calculating the LD50 requires more formulas and calculations than I intend to get into here (see the MPCA guidance). However, the process requires the gathering of information about the components of the waste and the use of a specified formula.
An alternative to calculating the LD50 is to apply specific and documented knowledge of the waste and the materials and processes used in generating the waste. You may rely on information provided by the manufacturer in making this determination.
If sufficient information is not available to determine if a waste displays the characteristic of Lethality, you may, after due diligence has been applied, manage the waste as Lethal hazardous waste or notify the MPCA in writing of your inability to make a determination. The MPCA will assist in the determination based on the information you provide.
A final resource available from the MPCA in determining if a waste exhibits the characteristic of Lethality is a list of wastes which the MPCA believes may be a Lethal hazardous waste but may not exhibit any of the attributes listed earlier in this article. This list of possible Lethal hazardous wastes does not include all Lethal wastes, only those which the MPCA believes may not otherwise be listed and of which it has specific knowledge; they are:
Specific known lethality information:
Waste name | CAS registry number | Approximate lethality threshold concentration |
Beryllium | 7440-41-7 | 2% |
Formaldehyde | 50-00-0 | 20% |
Glutaraldehyde | 111-30-8 | 27% |
Perfluorobutanesulfonate (PFBS) | 29420-49-3 | 86% |
Perfluorodecanoic acid (PFDA) | 335-76-2 | 11% |
Perfluorooctanesulfonate (PFOS) | 1763-23-1 | 50% |
Perfluorooctanesulfonylamide (FOSA or PFOSA) | 754-91-6 | 34% |
If you’ve read this far it’s likely that you either generate a hazardous waste in Minnesota, or you send waste to that state for treatment, storage, or disposal. I encourage you to review the MPCA guidance document for additional information. In addition to providing a more in-depth explanation of the Lethality characteristic than addressed in this article, it also has a wealth of contact information for the MPCA and the Metro County Hazardous Waste Offices.
Whether you need training to comply with the Federal regulations of the USEPA or those of your state; I can help. Also, if you require HazMat Employee training per the regulations of the USDOT/PHMSA; I can help. Public Seminars, Onsite Training, Web-Based Training, Self-Guided Training, or any combination of them all; I can help you to attain and maintain regulatory compliance. Please don’t hesitate to contact me with any questions.