Unknown Chemical Waste Disposal


An unknown is defined as a chemical in an unlabeled container for which the identity is unknown. Federal, state and local regulations specifically prohibit the transportation, storage, or disposal of wastes of unknown identity. In addition, hazardous waste disposal companies will not accept unknowns without proper analysis. Unknown or unlabeled chemicals require analysis prior to disposal. The analysis of a single sample can easily cost $1,000 or more. Unknown chemicals present serious legal and safety problems for the university.

The process for identifying an unknown chemical can be tedious and costly. However, some activities can be done to prevent the generation of an unknown as well as identifying an unknown.

Identifying Unknown Chemicals

Every effort should be made to properly identify an unknown chemical. The following steps should be taken to help identify an unknown chemical:

  • Consult with the Principal Investigator (PI) or Supervisor/Manager about the type of work that was being conducted.
  • Ask area personnel about the container. Someone may remember its contents.
  • Contact groups that previously used the area and see if they can recall the waste’s identity.
  • Simple tests such as pH may aid in identification. 
  • Check fresh reagents present; the waste was most likely derived from them. The field of possibilities can be greatly reduced in this manner.
  • Review projects currently in progress.

CAUTION:  Please do not open or handle an unknown if you suspect that it may detonate or react adversely. Proper precautions must be taken in the handling of any unknown chemical.

Preventing Unknown Chemicals

Prevent the generation of unknowns by:

  • Labeling all containers (including beakers and test tubes) properly. This should be done even when creating reagent solutions for temporary use. Labeling will also prevent using the wrong material accidentally.
  • Inspecting containers and labels periodically. Replace fading or deteriorating labels.
  • Label containers using chemical names, not abbreviations, chemical structure or formulae.
  • Maintaining an accurate inventory
  • Require all reaction mixtures stored in lab glassware to be labeled with chemical composition, the date they were formed, the name of the lab worker responsible and a note book reference. This information will assist to facilitate the disposal of the mixture in the event the lab worker responsible is not available.
  • Require all workers leaving to properly identify any unknown material before they leave the area or lab.


Removing Unknown Chemicals from the work area

If the identity of the unknown still cannot be determined, EHRS will identify, remove, and dispose of unknown waste for on-campus generators. However, the generator or generating department may pay a fee ($) per bottle fee for the analysis and identification of any unknown waste.

The following is a description of the process for unknown identification and disposal. Please note that this identification process is offered by EHRS for the purpose of chemical disposal only.

Upon receipt of the completed form(s), EHRS will assign a control number to each item. An EHRS representative will come and evaluate the unknown material. 

Related Information

Phone: 2-2520 or 215-707-2520 (off campus)

Request for Analysis of Unknown Material Form