Pollution Prevention

• Inventory Management
  • Maintain an up-to-date inventory of the chemicals in your laboratory to avoid re-purchasing existing materials and to understand usage patterns.
  • Only purchase the amount of chemical you will need in the short term.  Buying chemicals in bulk almost never makes financial sense when the risks of storage and the costs of disposal are considered.
  • Use the EHSA inventory system to identify coworkers in your area/DLC who might have a chemical that you need.
  • Dispose of outdated or unwanted chemicals immediately.  Some materials, such as peroxide-forming chemicals, become more dangerous over time.
  • Label all chemical containers, regardless of what’s inside. Unknown chemical wastes are extremely expensive to dispose of.
  • Only purchase cylinders from companies who will pick them up when empty, and avoid use of lecture bottles.

   

  Scaling and Substitution

  • Consider using microscale experiments to reduce the volume of chemical wastes generated.
  • Avoid unnecessary dilutions in experimentation which might increase the volume of hazardous waste generated.
  • Substitute less-hazardous materials into experiments. MIT’s Green Chemistry program provides excellent resources for the selection of solvents and other reagents to minimize the volume and toxicity of wastes generated, some specific examples include:
    • Use biodegradable Cyrene instead of dimethylformamide or n-methylformamide
    • Use latex paints and coatings instead of oil-based
    • Use non-mercury thermometers and equipment
    • Select non-mercury preservatives, and choose products such as antibodies which have been manufactured using non-mercury preservatives
    • Preserve specimens in ethanol instead of formaldehyde which is much more toxic
    • Use non-halogenated solvents in place of halogenated solvents wherever possible to reduce toxicity and disposal costs.  A good example is substitution of dichlormethane for ethyl acetate/ethanol for extractions and chromatography
    • Use ‘SYBR safe’ or other DNA gel stain instead of ethidium bromide
    • Substitute F-TEDA-B54 or other product in place of fluorinating agents
    • Use scintillation cocktails which are non-toluene/xylene based
    • Eliminate toxic metal catalysts whenever practical, even if it means longer experimentation times
    • Purchase chemicals pre-mixed or in the desired concentration to avoid unnecessary experimental steps and un-needed chemical stores
    • Purchase peroxide-forming chemicals with an inhibitor (BHT typically) whenever possible.  This increases the useful life of the reagent and reduces the hazards associated with it.
    • In shops with metal-cutting equipment, consider switching from petroleum-derived cutting fluids/coolants to those derived from castor beans or other plant sources.

Mixing Chemical Waste Streams

• In most cases, mixing hazardous chemical wastes with other materials (water, non-hazardous chemical wastes, etc.) results in more hazardous wastes; the entire mixture becomes hazardous waste.
  • Design processes and experiments so that chemical wastes are collected separate from other materials.
  • MIT EHS can assist in setting up chemical waste collection processes/areas to minimize unwanted mixing and unnecessary hazardous waste generation.
• Flammable liquids are the most cost-effective and efficient waste stream to dispose of.  Avoid mixing halogenated solvents, other hazardous materials, or large quantities of water with flammable liquid wastes.
• Wastes containing heavy metals should not be combined with any other waste streams.
• Mercury wastes should be kept separate from all other waste streams.

If you have any questions about waste minimization, substitution, optimization and mixing of waste streams, please contact the Environmental Health and Safety Department.

Wash and Re-use

Consider washing and re-using items such as glassware, tools and small equipment instead of disposing of them when they have chemical contamination.  In many cases washing, and collecting the clean-up materials and/or first rinse as chemical waste, will result in less hazardous waste generation than simply disposing of the soiled item.  MIT EHS can advise on which contaminants/items are good options for wash and re-use.

Solvent Recycling

In areas with high-volumes of solvent throughput, purchasing and operating a solvent recycling unit can be an excellent way to reduce wastes and costs.  Recyclers are available for acetone, IPA, xylene and many other solvents and offer a high grade of purity.  Note that labeling and record-keeping requirements exist for solvent recycling, and EHS should be contacted to evaluate the feasibility and safety of each operation.

Chemical Sharing/Reuse

Consider sharing and borrowing chemicals instead of purchasing new stocks, using the MIT EHSA chemical inventory system.  EHSA facilitates chemical sharing by allowing users to search chemical inventories within their department(s) for specific chemicals being shared by other labs.

Offer surplus chemicals that are in good condition to other potential users instead of disposing of them.  MIT EHS can facilitate a chemical exchange whereby chemical users post their unwanted, preferably unopened chemicals that would otherwise be disposed, for use by others who could use them.

Equipment Re-Use

If you have functional equipment in your lab or space that you no longer need, consider offering it for re-use via MIT’s RHEAPLY platform.  RHEAPLY is an on-line asset exchange management program for the MIT community which allows the free transfer of equipment and supplies among MIT users.