Principles into Practice Setting the Bar for Green Chemistry

R ecent years have seen a disheartening string of revelations in which everyday items once considered safe—food packaging, toys, clothes, furniture, electronic components, and many more products—are found to contain carcinogens, endocrine disruptors, and other harmful chemicals. Growing demand for healthier alternatives, already seen in food production and housing construction, is also happening at the building-block level of manufacturing, where so-called green chemistry represents a revolutionary change in preventing pollution and health problems starting at the chemical design stage. Many industry and government entities are beginning to espouse the principles of green chemistry on their websites and in public statements. Now comes the task of crafting policy to put those principles into action. The U.S. Environmental Protection Agency (EPA) defines green chemistry as “the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances. Green chemistry applies across the life cycle of a chemical product, including its design, manufacture, and use.” Green chemistry also aims to mitigate the type of uncertainty Alan Goldberg, a professor of toxicology at the Johns Hopkins Bloomberg School of Public Health, recently described to The New York Times: “I can get [toxicity] information on only 20 percent of chemicals we interact with on a daily basis.” Of that 20%, he now says, he may be able to find information on overt toxicity for about half, but for details on specific effects such as developmental neuro toxicity, the figure shrinks toward zero. So what does green chemistry look like? Consider the example of pregabalin, the active ingredient in the neuropathic pain drug Lyrica®. Pfizer developed an alternative greenchemistry process that converted several steps of pregabalin synthesis from use of organic solvents to water. That reduced both health hazards and production heating requirements. With the new synthesis, waste from the process dropped from 86 kg of waste per kg product to 17 kg, and energy use dropped by 82%. Proponents say that’s how the field can offer a win–win–win solution: good performance, lower cost, and less environmental impact—what Richard Engler, program manager of the EPA Green Chemistry Program, calls the “triple bottom line.” For many, a standard is a logical next step. “At some point you have to go beyond a definition and principles,” says Engler. “I think that’s something the standard will enable.”