By Peter Mirtchev, Member-at-Large for the GCI and Laura Reyes, Co-Chair for the GCI
All chemists create chemical waste, it’s simply part of our job. Recently, we started a Waste Awareness Campaign to track the amount of waste being generated by our chemistry department. Aside from this, the chemical waste disposal process was a bit of a mystery. Learning how to properly sort, label, and dispose of chemical waste should be part of every chemists’ early training, but typically gets overlooked. In academic research labs, waste disposal habits tend to get passed down from one person to the next, and often stem from tradition rather than regulation. With this post, we hope to clarify some of the confusion surrounding proper disposal of different types of chemical waste.
We recently co-hosted a seminar about waste disposal with the Chemistry Students’ Union. Our speakers were Ken Greaves (Chemistry Department Supplies & Services Supervisor) and Rob Provost (Environmental Protection Manager at the UofT EH&S Office). We found that many members of the department had important questions regarding proper disposal practices and what happens to chemical waste after it is picked up. We have summarized the crucial points of the talk in Q&A format below. There’s also very useful information at this EH&S website on chemical waste. If you have other unanswered questions regarding chemical waste, leave them in the comments and we’ll get them answered for you!
Disclaimer: the information below is specific to the Department of Chemistry at the University of Toronto, and may change according to institution. Check with your own institution regarding the rules of chemical waste disposal.
Q: What are the most common types of chemical waste produced in a research laboratory?
A: Solvents. At the University of Toronto, the three most common chemicals are 1) acetone, 2) hexanes, and 3) dichloromethane. The Department of Chemistry purchases over 10,000L of acetone per year alone.
Q: What is considered ‘flammable’ waste?
A: A flammable liquid is one that has a flashpoint of 23.8°C or lower.
Q: Is a mixture of water and organic solvents considered aqueous or flammable waste?
A: If the mixture is more than 50% water, it is considered aqueous waste. If it is less than 50% water, it is considered flammable waste. If the amounts are uncertain, treat as aqueous (see below for more about the treatment of waste types).
Q: What mixtures are treated as chlorinated waste? Continue reading