3.4 Practical Frameworks and Tools

Green Chemistry

Green chemistry, now a recognized field of research and design activity, grew from the awareness that conventional ways to synthesize chemicals consumed large amounts of energy and materials and generated hazardous waste, while the final products themselves were often toxic to humans and other life and persisted in the environment. Hence green chemistry seeks to produce safer chemicals in more efficient and benign ways as well as to neutralize existing contaminants. Such green chemicals typically emulate the nontoxic components and reactions of nature.

1,300 Liters of Solvent for 1 Kilogram of Viagra

Green chemistry emerged as a field after the US Environmental Protection Agency (EPA) began the program "Alternative Synthetic Pathways for Pollution Prevention" in response to the 1990 Pollution Prevention Act. In 1993 the program, renamed "Green Chemistry," established the Presidential Green Chemistry Challenge Award to encourage and recognize research that replaces dangerous chemicals and manufacturing processes with safer alternatives. Recent winners of the award have created ways to make cosmetics and personal products without solvents and an efficient way to convert plant sugars into biofuels. In 1997, the nonprofit Green Chemistry Institute was established and would later become part of the American Chemistry Society. The following year, the Organization for European Economic Development (OECD) created the Sustainable Chemistry Initiative Steering Group, and Paul Anastas and John Warner's book Green Chemistry: Theory and Practice established twelve principles for green chemistry. Recognized as leaders in the green chemistry field, Anastas and Warner have continued to advance the ideas through innovation, education, and policy, with Warner helping to create the Warner Babcock Institute to support this mission. Paul Anastas, meanwhile, was confirmed as head of the EPA's Office of Research and Development in 2010. Their green chemistry principles are reflected in a hierarchy of goals set by the Green Chemistry program:

  1. Green Chemistry: Source Reduction/Prevention of Chemical Hazards

    • Design chemical products to be less hazardous to human health and the environment*
    • Use feedstocks and reagents that are less hazardous to human health and the environment*
    • Design syntheses and other processes to be less energy and materials intensive (high atom economy, low feed factor)
    • Use feedstocks derived from annually renewable resources or from abundant waste
    • Design chemical products for increased, more facile reuse or recycling
  2. Reuse or Recycle Chemicals
  3. Treat Chemicals to Render Them Less Hazardous

  4. Dispose of Chemicals Properly

    *Chemicals that are less hazardous to human health and the environment are:

    • Less toxic to organisms and ecosystems
    • Not persistent or bioaccumulative in organisms or the environment
    • Inherently safer with respect to handling and use

Figure 3.8 Goals for Production of Green Chemicals

James Clark, a chemist who leads the Green Chemistry Centre of Excellence at the University of York, England, has summarized the goals of green chemistry in an octagon. This octagon likewise stresses efficiency, renewable feedstocks, and human and environmental health.

Green chemistry also refers to a journal devoted to the topic (Green Chemistry), and one of its associate editors, Terry Collins, has identified steps to expand green chemistry. First, incorporate environmental considerations and sustainability ethics into the training of all chemists and their decisions in the laboratory. Second, be honest about the terms green or sustainable and the evidence for the harm chemicals cause. For instance, a cleaner, more efficient way to produce a certain product may be progress, but if the product itself remains highly toxic and persistent in the environment, it is not exactly green. Consequently, "since many chemical sustainability goals such as those associated with solar energy conversion call for ambitious, highly creative research approaches, short-term and myopic thinking must be avoided. Government, universities, and industry must learn to value and support research programs that do not rapidly produce publications, but instead present reasonable promise of promoting sustainability".

Collins has devised ways to degrade toxic chemicals already in the environment. He formed a spin-off from Carnegie Mellon University, GreenOx Catalysts, to develop and market his products, which have safely broken down anthrax as well as hazardous waste from paper pulp mills. Green chemistry, however, does not exist merely in government or university enclaves. In 2006, the Dow Chemical Company, with annual sales over $50 billion, declared sustainable chemistry as part of its corporate strategy. DuPont, meanwhile, created a Bio-Based Materials division that has focused on using corn instead of petroleum to produce polymers for a variety of applications, from carpets to medical equipment, while also reducing greenhouse gas emissions. Since synthetic chemicals are the basic building blocks of most modern products, from shoes to iPhones to food preservatives, green chemistry can play a significant role in sustainability. Cradle-to-cradle design, earth systems engineering, and virtually every other framework and tool can benefit from more environmentally friendly materials at the molecular level. As John Warner, a key figure in educating companies about green chemistry providing innovation and new materials across sectors, states,

The field of chemistry has been around in a modern interpretation for about 150 years, [and] we have invented our pharmaceuticals, our cosmetics, our materials, in a mindset that has never really focused on sustainability, toxicity, and environmental impact. When one shifts to thinking in that way, it actually puts you in a new innovative space. In that new innovative space, that is the hallmark of creativity. What companies find is instead of it slowing them down, it accelerates time to market because they run into less hurdles in the regulatory process and in the manufacturing process. And it puts them in spaces that they weren't normally in because they've approached it from another angle. Chemicals policy creates the demand. Green chemistry is not chemical policy. Green chemistry is the supply side, the science of identifying those alternatives. And so hand in hand, those two efforts accomplish the goals of more sustainable futures. But they're not the same.