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ChemWiki: The Dynamic Chemistry Hypertext > Reference > Lab Techniques > Safety > Waste Disposal

Waste Disposal

Different countries, states, localities, and institutions have different, often stringent, laws governing hazardous waste disposal. Failure to follow these laws can result in expensive cleanups, fines, and getting your ass fired. Check with your enviromental safety officer for a complete list of rules and a long boring lecture on how to properly dispose of hazardous waste. Usually this requires specially labeled containers and scheduled pickups. However, most of the rules can be generalized under a few guidelines which should always be kept in mind when dealing with chemical waste.

Things That Should Never Go Down the Drain

These materials should be disposed of in properly labeled liquid waste bottles.

  • Heavy metal containing solutions.
  • Organic/halogenated solvents
    • There are a few organic solvents, such as ethanol, which can be disposed of down the drain. Again, check with your enviromental safety officer for local rules and regulations.
  • Strong, undilluted acids and bases
    • These can cause physical damage to the plumbing. Use bicarbonate to neutralize acids, and dillute sulfuric acid to neutralize bases. Check the pH with a strip. When it is neutral it is often OK to dispose of them down the drain
  • Biohazardous liquids
    • It is acceptable to decontaminate some biohazardous solutions with bleach or similar disinfectants and dispose of them down the drain, others must be autoclaved. Again and always, check regs.
  • Radiological Hazards
    • These usually require more specialized treatment

Things That Should Never Go in the Trash

  • Sharps
    • Special containers should be available for needles and broken glass
  • Biohazardous Solids
    • These usually must be autoclaved. Make sure you are using autoclavable bags/containers to do so
  • Anything on the previous list

Special Considerations

Consult a list of chemical incompatibilities before adding a chemical to a waste bottle. Some incompatabilities are:

  • Acetone and concentrated nitric acid
  • Cyanide and acid

Chemicals which are reactive or pyrophoric can not be simply disposed of and must be quenched.

Some chemials are not particularly hazardous, but have unplesant odors. These should be destroyed before placing them in waste containers exposed to the laboratory enviroment. Some examples are:

  • Sulfides, disulfides, thiols
    • These can be destroyed (through oxidation) with bleach

When left exposed to the atmosphere for long periods of time, some chemicals form peroxides which can detonate when disturbed. Stocks of these chemicals should be periodiclly rotated. Some peroxide forming materials are:

  • Ethers
    • Especially diisopropyl ether
  • Molecules with benzylic or allylic hydrogens


  • ChemJobber, Chemoptoplex

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Last modified
11:08, 29 Mar 2014



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This material is based upon work supported by the National Science Foundation under Grant Numbers 1246120, 1525057, and 1413739.

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