Green Chemistry Initiative

at the University of Toronto

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What is Green Chemistry?


With growing concerns over climate change and increasing pollution and waste production in the world, we all have a responsibility to help protect our forests, our oceans and our environment. The green chemistry philosophy is based on just that. 

“Green chemistry” is the general practice across all fields and domains of chemistry of reducing the use and production of harmful chemical compounds in any and all syntheses and processes, at both a research and industrial level.  In addition, the aim of green chemistry is to reduce the amount of energy and resources required by the chemical industry for a given chemical reaction while maximizing the efficiency and yield of the process.

The 12 Principles of Green Chemistry, first established by Anastas and Warner in 1998 and listed below, are the guiding principles upon which green chemistry was founded.  The principles serve as the basis on which chemical reactions can be compared and evaluated for their efficiency and environmental impact, and are an excellent tool for both chemists and engineers, in both academia and industry, to minimize their environmental footprint. 

The 12 principles of Green Chemistry are as follows:
  1. Prevention: It is better to prevent waste than to treat or clean up waste after it has been created.
  2. Atom Economy: Synthetic methods should be designed to maximize the incorporation of all materials used in the process into the final product.
  3. Less Hazardous Chemical Syntheses: Wherever practicable, synthetic methods should be designed to use and generate substances that possess little or no toxicity to human health and the environment.
  4. Designing Safer Chemicals: Chemical products should be designed to affect their desired function while minimizing their toxicity.
  5. Safer Solvents and Auxiliaries: The use of auxiliary substances (e.g., solvents, separation agents, etc.) should be made unnecessary wherever possible and innocuous when used.
  6. Design for Energy Efficiency: Energy requirements of chemical processes should be recognized for their environmental and economic impacts and should be minimized. If possible, synthetic methods should be conducted at ambient temperature and pressure.
  7. Use of Renewable Feedstocks: A raw material or feedstock should be renewable rather than depleting whenever technically and economically practicable.
  8. Reduce Derivatives: Unnecessary derivatization (use of blocking groups, protection/ deprotection, temporary modification of physical/chemical processes) should be minimized or avoided if possible, because such steps require additional reagents and can generate waste.
  9. Catalysis: Catalytic reagents (as selective as possible) are superior to stoichiometric reagents.
  10. Design for Degradation: Chemical products should be designed so that at the end of their function they break down into innocuous degradation products and do not persist in the environment.
  11. Real-time analysis for Pollution Prevention: Analytical methodologies need to be further developed to allow for real-time, in-process monitoring and control prior to the formation of hazardous substances.
  12. Inherently Safer Chemistry for Accident Prevention: Substances and the form of a substance used in a chemical process should be chosen to minimize the potential for chemical accidents, including releases, explosions, and fires.

With these principles in mind, the goal of the Green Chemistry Initiative at the University of Toronto is to educate both the university population and the general public on the use and implementation of these principles, and to promote the practice of environmentally-friendly chemistry not only in the Department of Chemistry but in all chemistry-related organizations. 

For more information on the 12 Principles of Green Chemistry, including full detailed descriptions of each principle, please visit the ACS Green Chemistry Institute link.