Q & A: Mastering the Molecule

Yale professor Paul Anastas has a vision of the future: better living through chemistry. No, really

A boyish-looking 45, Paul Anastas has already long been known as the father of green chemistry -- a field he defines as "the design of chemicals and chemical processes that reduce harm to humans and the environment." It involves inventing not only safer chemicals but also processes that produce less, and less hazardous, waste, and which are based on renewable raw materials. In 1989 he joined the Environmental Protection Agency, becoming chief of the industrial chemistry branch and director of the agency's program in green chemistry -- a term he coined. In 1997, while he was still in government, he helped found the private Green Chemistry Institute, which now has chapters in 24 countries. This January he took up a position as professor of green chemistry at Yale. In his 1817 saltbox house near New Haven, Connecticut, Anastas seated himself next to an antique phonograph and other bits of old-time technology that he treasures and talked with science journalist Kevin Krajick.

Many people assume chemists are evil -- they inevitably cause pollution.
People don't know we have the option of doing things green. They think that in order to have cars, computers, and other modern conveniences, we need to generate all kinds of nasty poisons. Green chemistry is disproving that myth every day.

What's really new about it?
We're touching on something not done historically, which is to design molecules with an eye to consequences, right from the start. You go back to the basic chemical properties -- volatility, electronic properties, boiling point. That way you can design a molecule to do exactly what you want. If you just try to deal with a particular hazardous outcome -- cancer or poisoning or explosions -- then you're addressing things piecemeal. If you go back down to the molecular architecture, you can address a wide range of issues.

Have science and technology evolved to the point where we can do that?
Scientists are now inventing or discovering 4,000 new chemicals a day. We can make something blue or red, or rubbery or brittle, and the whole reason is our command of how molecules work. Because we know more about the mechanisms of toxicity, both in the body and in the biosphere, we can build molecules that eliminate, or at least greatly reduce, a wide range of hazards. I should probably add that we will never reach perfection. Nothing will ever be perfectly green.

Has green chemistry actually taken hold anywhere?
I could give you hundreds of examples of award-winning technologies, used by companies in the United States, the United Kingdom, Japan, Italy, that have eliminated literally billions of pounds of hazardous substances. It goes from the way we make pharmaceuticals or electronics to the way we raise crops or paint the bottoms of boats. That said, for every one process or product that uses green chemistry, there may be a hundred or more that have yet to be considered. So 99 percent of the work is still left.

Give me a few examples of things we're using now, or will be using soon.
Sure. Polylactic acid is a plastic whose molecule is made from potatoes, corn, and other plant sources. Wal-Mart put in multimillion-pound orders a year ago for cups, soup containers, food packaging -- it's just getting going. Arsenic in treated lumber has been recognized as a problem, and green chemistry has come up with a water-based alternative. There's also supercritical carbon dioxide -- that is, CO2 put under high pressure so it becomes a fluid [in this form it does not contribute to greenhouse gas emissions]. It's now used in many processes that previously used some fairly toxic solvents. That includes decaffeinating coffee, which historically used methylene chloride, a cancer suspect that is also used for stripping paint. CO2 is also used in dry-cleaning, which up to now has typically used a toxic chemical called PCE.

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