The Green Chemistry Revolution

An Interview with Paul Anastas

Paul Anastas is frequently referred to as the “father of green chemistry.” He is director of the Center for Green Chemistry and Green Engineering and the Teresa and H. John Heinz III Professor in the Practice of Chemistry for the Environment in the School of Forestry & Environmental Studies at Yale University.

Multinational Monitor: What is green chemistry?

Paul Anastas: The formal definition of green chemistry is the design of chemical products and processes that reduce and eliminate the use and generation of hazardous substances.

That's the formal definition. An important point of that definition is that it views chemistry not as simply one industrial sector or one academic department. It views chemistry in its most fundamental dictionary definition - the study of matter in all of its transformations. So it really affects everything that we see, touch and feel, and all of the materials that make up the basis of our society and our economy, including the materials that are used to generate, store and transport our energy.

MM: Why is there a need for something called green chemistry, and how does it differ from traditional chemistry?

Anastas: Historically, chemistry has engaged in tremendously creative, really brilliant and effective science that has given us modern conveniences of communication, transportation, computation, life-saving medicine. It had tremendous accomplishments in getting performance and functionality that is really one of the great achievements of our civilization.

What the field of chemistry hadn't mastered, historically, is how to get that performance, how to make these achievements, without generating tremendous amounts of toxic waste or making the products themselves so that they were not harmful to humans or the environment. Green chemistry is adding on to the accomplishments of traditional chemistry by getting all of these achievements in ways that are sustainable and environmentally benign.

MM: One of the principles that you've espoused for green chemistry is reducing waste. What does that mean and why is it significant?

Anastas: Looking generally at how products are manufactured in the industrialized world, about 5 or 6 percent of the inputs - the raw materials that go into a manufacturing process - wind up in the final product. Ninety-four percent or 95 percent wind up as waste. That's across all industry sectors. There are some industry sectors which are far less efficient even than that - where you generate one pound of product and you generate one ton of waste.

MM: What are the reasons, technical or social, that there is a 20-to-1 ratio of waste to output?

Anastas: Historically, we've dealt with maximizing the value of the product that you produce. As long as the value of the product was economically beneficial, then the costs of waste were historically very, very low and unimportant.

Now that the actual impacts of waste - whether on worker safety, consumers, neighborhoods or the environment - are better understood, there's a greater understanding of all of the drivers to reducing waste. You could focus on the hazardous waste that is generated that's toxic and bad for people and the environment. But even those substances that are not as toxic represent a hazard to the bottom line - any waste, whether hazardous or not, necessarily requires it to be separated from the product and transported off-site. All of that takes time and money. So, these wastes are either hazardous to humans or the environment, or hazardous to the process and the economic bottom line.

MM: Another one of the green chemistry principles that you've outlined is to change the feedstocks that are used. How central to your story is moving away from petroleum-based chemistry to other inputs?

Anastas: Right now, of the materials that are made by man, certainly more than 90 percent, probably closer to 95 percent of those materials, are made from petroleum-based feedstocks. Petroleum is necessarily a limited feedstock; a finite depleting resource. If we're looking at fundamental sustainability of our products and processes, we want to make sure that we move to things that are renewable - renewable either from bio-based sources or renewable in terms of using waste materials as feedstocks and processes. So this is one very important component of green chemistry.

The 12 Principles of Green Chemistry look across the lifecycle of any product or any process, from the origin of the feedstock, how it's manufactured, the design of the product, through its end of life. It really is a comprehensive look at the impacts and consequences of products and processes.

MM: In terms of the feedstock issues, how doable is it now or in the foreseeable future to switch from petroleum inputs to other ones?

Anastas: There is nothing in the laws of chemistry or physics that make the transformation to renewables impossible. This is a relatively new area of focus. We focused in the 20th century on how to convert petroleum-based feedstocks to products. In the 21st century, there's far more focus on how to convert bio-based feedstocks into useful materials. It can happen. It's no different from any other type of discovery, development or innovation.

MM: Is green chemistry altogether different science than traditional chemistry?

Anastas: Green chemistry is actually taking a lot of the same knowledge, the same skills, the same understanding, and doing it with a new perspective. So, you're taking the same fundamentals of molecular understanding and pointing it in the direction of, "How do we redefine efficiency?" "How do we redefine performance?" "How do we redefine elegance in a way that includes the impact on humans and the environment and making sure that it's a much more holistic design?" We view hazard as a design flaw. If something is hazardous to humans or the environment, then you have more design work to do.

MM: What are some examples of how green chemistry is working now and changing either manufacturing processes or consumer products?

Anastas: There's a wonderful collection of some of the great achievements in green chemistry, called the Presidential Green Chemistry Challenge Award. It was established about 13 years ago by President Clinton. These are recognitions for accomplishments in green chemistry by industry, small business and some by academia. The great story about green chemistry is not any one achievement, product or company, but the breadth of achievements.

Just looking at these award-winning technologies, they represent everything from traditional chemicals to packaging, from agriculture to energy, pharmaceuticals, cosmetics, building materials, and everything in between. The fact that green chemistry is applicable to this broad sector of products and processes, I think is the real achievement. Just the winners of this prize, not even the hundreds of nominees, have, according to the EPA, removed enough hazardous substances to fill train cars hundreds of miles long.

MM: You're explaining a view of chemistry that's very broad and related to almost everything in the economy. How significant are green chemistry applications now, in the context of the overall economy?

Anastas: There's a two-fold answer to that question, which is good news and better news. The good news is the list of accomplishments of products and processes and industry sectors. I could name hundreds of companies and thousands of products that have been affected by green chemistry, either in the product design or the manufacturing process. And green chemistry has spread from the United States, Europe and Japan to developing nations including emerging economies like China and India.

That's the good news. The great news is that all of those accomplishments represent a fraction of the power and potential of green chemistry. We're probably talking about 5 percent, at most, perhaps only 1 percent, of the power and potential of green chemistry to affect products and processes.

MM: What kind of funding and institutional and corporate support exists right now for green chemistry initiatives?

Anastas: There's a tremendous amount of investments that are being done in the research labs both in industry and in academia. There is, however, a dramatic underinvestment in formal programs targeted by the federal government, by the research funding agencies and even in the industry toward the research and development of these new technologies. What needs to happen is investment in these new green chemistry technologies in order to catalyze these new innovations.

MM: What are the existing incentives for investing in green chemistry?

Anastas: Green chemistry is catching on not only because it's a great scientific leap forward, but because it allows companies to meet their environmental and economic goals simultaneously. There's not a single regulation or law saying, "Thou shalt do green chemistry." Companies are embracing green chemistry because it allows them to meet their environmental goals, and even their regulatory goals, in ways that are profitable, increase competitiveness, and impart new performance and capabilities into their products and their processes. So, that is the biggest incentive from the industrial side of things. That's why you're seeing these energy, cosmetics, pharmaceutical, plastics and polymers companies, and others, doing this.

From the academic side, people are doing this because it is simply more elegant chemistry. There are great scientific challenges facing green chemistry and great scientists want to take on great challenges. That is why you're seeing wonderful work going on at Yale, Carnegie Mellon University, the University of Oregon, and so many other universities around the world.

MM: What kind of support is there from the U.S. federal government?

Anastas: The support from the federal government is diffuse. There is currently a bill on Capitol Hill - the Green Chemistry Research and Development Act - that would provide some funding though the National Science Foundation, the Environmental Protection Agency and the Department of Energy. But currently the vast majority of any support for green chemistry is spread throughout diffuse programs on things like renewable energy, degradable polymers and catalysts, and not focused on green chemistry as such.

MM: Is that a problem?

Anastas: Yes. There needs to be increased, focused funding for green chemistry.

MM: What can you say about the leading companies, Dow, Dupont, or others in the pesticide field - what has been the level of their interest?

Anastas: The best reflection of the interest from industry is seen in the Presidential Green Chemistry Challenge Awards. There you see a tremendous focus from pharmaceutical companies that are making very complex molecules and doing them in a way that is far more efficient and generating far less waste. You're seeing it in cosmetic companies to ensure that all of their ingredients are moving greener and greener. You're seeing it from packaging companies, moving away from persistent, toxic, bio-accumulative substances into ones that are far more environmentally benign.

MM: With each of those three examples, there have been consumer and environmental campaigns focused on waste and toxic-related issues. What is the correlation between those campaigns and the initiatives from industry?

Anastas: Innovation often follows awareness. There are a range of drivers that will motivate companies to innovate - some of the drivers will be increasing the profitability of their companies and the profitability of their products. Some of the drivers will be wanting to get savings and efficiencies during difficult economic times. Some drivers will be regulatory and environmental campaigns. There's a range of drivers out there that are motivating companies to move.

The good news is all of these drivers are pointing in the same direction, and that's the direction of green chemistry.

MM: The last of your dozen Principles of Green Chemistry is minimizing the potential for accidents. To what extent have you seen workers and unions pushing for these kinds of technological changes as a way to enhance worker safety?

Anastas: There is burgeoning interest and burgeoning awareness by the labor unions that these types of new, innovative technologies - offering green-collar jobs related to green chemistry and green engineering - are good for jobs, good for the working environment, good for worker health and safety. Recently, the United Steel Workers asked if they could hold a training conference run by the Center for Green Chemistry and Green Engineering at Yale on how to train their workers in this area of green chemistry. That training is now moving forward for the workers. We trained the trainers.

There has been recent interest expressed by other major labor unions in the same type of training. This type of awareness - that green chemistry and green engineering aligns with their interest to preserve jobs, to create better jobs, to have a safer working environment, and to prevent accidents - is growing. It's a very good alignment.

MM: Given the story you're telling of all of these factors converging in a positive way, why isn't there more momentum?

Anastas: Actually, the pace, I think, in chemistry and engineering is a diffusion-controlled reaction - that means as soon as things spread, they are able to react. What we're seeing is this is also diffusion-controlled. It's about awareness of what is possible. When people - whether from the scientific, industrial worker or government policy point of view - realize that green chemistry is fundamentally rooted in science, technology and innovation, and focused on solutions rather than just quantifying problems, they are all looking to build green chemistry into their work.

MM: You emphasize some of the great scientific challenges. What are a couple of the big challenges facing green chemistry?

Anastas: A comprehensive understanding of the molecular basis of hazard, of toxicity, so that we can design things that are never toxic. That is the holy grail; it's almost the goal of perfection that we are seeking. That's the great scientific challenge. There are many others as well but this is the most fundamental.

MM: Are there any challenges that are closer to the consumer level?

Anastas: Closer to the consumer level, a major challenge is to ensure that our products last as long as we need them to last, and then degrade into the environment, so that they don't persist and bio-accumulate. We have designed things so that they will be practically immortal. That used to seem like a good thing, until we wound up recognizing that it's not good if they survive forever in landfills, or, worse, bio-accumulate in our bodies. So we want things to last every bit as long as we want them to and not a second longer. And that's a great scientific challenge.

MM: How does green chemistry intersect with nanotechnology?

Anastas: Tremendously. On the plus side, nanotechnology will be absolutely essential to a sustainable civilization because it has the promise of giving us the performance and function that we need with dramatically less material - perhaps 10,000 times less material needed to get the same function. However, we need to do the right things right, and we tend to do the right things wrong, which would be doing nanotechnology and having it be hazardous to humans or the environment. So we need to design our nano materials so they are unable to be bio-available, threaten our environment or cause toxicity. That's what green nanotechnology is all about.

I give tremendous credit to the work going on at the University of Oregon on green nanotechnology. This is using the 12 Principles of Green Chemistry in order to design this next generation of nanotech, which can be described as getting all the applications of nanotechnology - whether it be medicinal devices or electronic devices or sunscreens and things - without the implications, such as substances getting into the lungs and respiratory system, crossing blood brain barriers, getting into fish gills or getting into our water. So green nanotechnology is applications minus implications.

MM: Are those things that you can solve with a high degree of confidence at the design level? What will be the role for monitoring, particularly after these new technologies are introduced into the environment?

Anastas: You always want to be humble and validate that anything you're considering releasing into the environment or exposing to people is not going to be harmful. That said, I do have a lot of confidence that by starting out at the basic physical/chemical property level, that you can do a tremendous amount to reduce hazard.

MM: Are there any developments that are on the cusps of real breakthroughs?

Anastas: The many exciting green chemistry technologies that are emerging with the potential to make great impact are too numerous to list comprehensively. However, a few examples include the ability to split water with visible light to power a sustainable hydrogen economy; the introduction of new catalysts that will allow us to purify water without using toxic substances like chlorine; bio-based polymers that are non-toxic and also biodegradable; and green electronic devices that will both perform better and have a lower environmental impact. These are just a few of the many areas that people can look forward to seeing green chemistry innovations.