If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.


Green Chemistry

Empowering a sustainable world

These members of the new guard of scientists are using systems thinking to make green chemistry mainstream

by Melody Bomgardner and Rudy Baum
July 13, 2018


Last month, around 500 chemists and related scientists, businesspeople, and policy experts gathered in Portland for the 22nd Green Chemistry & Engineering Conference, hosted by the ACS Green Chemistry Institute.

This year’s conference included the usual deep dives into making chemical synthesis safer and more efficient. But several sessions took a broader view to see how green chemistry can make everyday consumer goods—not just eco-branded products—sustainable. That takes more than good chemistry—it requires the ranks of green chemists to grow, science-based environmental and health policies to flourish, and manufacturing industries to change how they operate.

C&EN caught up with GC&E speakers Joe DiSimone, Edward Brush, Grace Lasker, and Julie Zimmerman to find how green chemistry and society intersect. Read on to find out what these leading chemists had to say about green chemistry and social justice, public policy, the future of manufacturing, and the making of tomorrow’s scientists. Interviews have been edited for length and clarity.

Joe DeSimone

DeSimone is CEO and cofounder of 3-D printing firm Carbon and a chemistry professor at the University of North Carolina, Chapel Hill, and NC State University. Carbon is not DeSimone’s first business venture. In the 1990s, he developed a process, based on supercritical CO2, to produce fluoropolymers without the use of biopersistent surfactants. The process was licensed to DuPont. In 2004, he cofounded Liquidia, which combined manufacturing aspects of the semiconductor industry along with roll-to-roll manufacturing to make drug particles in precise shapes for improved delivery to the body.

Photo of Joe DeSimone.
Credit: Joe DeSimone

Can you tell us about what you’ve been doing recently at Carbon?

As cofounder and CEO of Carbon, I’m heavily involved in building the team and our strategy, and I’m now involved in scaling the technology and manufacturing. My hand is on the tiller. We’re approaching 300 employees and have raised over $400 million dollars.

Our digital fabrication technique for polymer parts is really brand new. It’s a big leap for the manufacturing of polymers, which today are mostly injection molded. I make the analogy to 2-D printing: In the old days, we had mimeograph machines that required a master template to make lots of copies. Then digital laser printers changed everything—how people work, how they collaborate, and even the supply chain. Laser printers enabled print on demand. Now we’re driving a lot toward production, and we build all our own 3-D printers.

We’ve established a global chemical supply chain through a multitude of partners, and that is growing. At the end of day, the chemical supply chain is one of the most important parts of this business. Each new resin opens up a new property-product market fit for our hardware, software, and resins.

Because you’ll be speaking at a green chemistry conference, what do you see as the main environmental benefits of 3-D printing?

We call it digital sustainability. Because we have a digital fabrication technique, we can do important things like remove unneeded materials from parts to strip them down to lightweight parts. We can reduce mass by 30–40% for cars. That leads to more fuel efficiency. We will have resins in the next Adidas shoes made from biobased, renewable feedstocks. That’s a huge focus, and now there are also resins coming out that are recyclable. So many polymers that are used today are not recyclable. We’re on this cusp of a new era in polymer science such that recyclability and renewable feedstocks have to be front out of the gate.

Also, we know polymers densify with time; they age, hydrolyze, and fade. For preservation, polymer parts are stored for decades in climate-controlled buildings that consume energy. Wouldn’t it be better to have a warehouse in the clouds and make on-demand inventory? Also, you don’t even have tools to store, as in injection molding. You can really free up inventory and capital—the whole gamut.

Carbon is not your first manufacturing start-up. What are some key things you have learned about manufacturing that you think academics and students interested in green chemistry should know or understand?

You have to think about implementation. You can do all the things you want to do in the lab and publish papers, but if no one implements it, it will do no one any good. This really leads to entrepreneurship and thinking financially about what it takes to really move the needle. That means knowing the whole product life cycle and being a systems thinker, not just going deep on one piece of the puzzle. We’re interested in people thinking through how you actually get things done and make a difference for the environment.

Being a systems thinker means leveraging both your liberal arts and science training. Like if you were an earthquake engineer in Haiti, you have to understand the language, culture, and politics of the place. You need real breadth of thinking. As chemists we have to think more broadly about environmental stewardship and our implementation.

As a chemist, inventor and entrepreneur, how do you figure out if a problem is a good business opportunity, and how can green chemistry fit into that equation?

What is quite clear is we as a society have lots of interesting problems to work on—environmental stewardship and the role the chemical industry plays. Not a week goes by that people aren’t producing a plastic that whales get entangled in or generating lithium-ion batteries that catch fire. It’s about being generally aware.

Chemists have a toolbox, but they often don’t own the problem. Instead, the problems may be owned by physicians or civil planners. Use your toolbox. Read Bill Gates’s annual letter, read the New York Times, read and understand where the problems are. Hang out with people who are different from yourself. We learn the most from people we have the least in common with. Chemists hanging out with chemists won’t expose you to diverse thinking about where the big problems are. It is incumbent on chemists to do those things.

News headlines these days point to materials of convenience, like plastics and perfluorinated chemicals, that persist in the environment. In your opinion, is it still green chemistry if we follow green chemistry principles to synthesize materials, but they persist in the environment?

I absolutely think one has to look at this from a systems level. Following principles of green chemistry doesn’t wipe your hands of responsibility. Green chemistry is not a green light on its own. It’s important and timely, given this conference, to focus on that.

At Carbon, we’re going to transform how polymers are made into parts. But recyclability and biobased feedstocks are important to us to prevent those parts from later becoming pollution. Green chemistry is important in principle, but we have to look at a systems level to make sure that what we do is right on all levels.

Edward Brush and Grace Lasker

Photo of Edward Brush.
Credit: Edward Brush
Photo of Grace Lasker.
Credit: Grace Lasker

Brush, a chemistry professor at Bridgewater State University, and Lasker, a Senior lecturer and director of health studies at the University of Washington, Bothell, jointly organized a conference session about the connection between green chemistry and environmental justice.

How do you think green chemistry connects to environmental justice?

We view environmental justice as the state where all people, regardless of gender, age, race, or economic status, have the right to live, work, play, and learn in healthy and safe environments. Chemicals enable the function we demand from consumer products. However, chemists also need to be aware of the potential unintended consequences of chemicals on human health and the environment.

Green chemistry is the science of making smart choices in how we design, make, use, and dispose of chemicals and chemical products. We believe that innovative green chemistry technologies have excellent potential to offer solutions to achieve equity and environmental justice.


What do you hope this symposium accomplishes?

Ever since the first of these symposia, held at the 2016 GC&E conference in Portland, we’ve used this opportunity to facilitate discussion and listen. We’re learning how different sectors of the chemical enterprise interpret the topics of equity and environmental justice and their connection to green and sustainable chemistry.

The feedback has helped us to better design our symposia into something that is productive for the speakers, participants, and the discipline. For example, at this year’s conference, we’re following our Monday afternoon symposium with a Tuesday evening workshop to explore topics in greater depth. Furthermore, we will be exploring how the American Chemical Society and the chemical enterprise can contribute to achieving the United Nations Sustainable Development Goals.

What are the main points you hope symposium participants took away from yesterday’s session?

First, we tried to make the point that we are not looking to create or promote a narrative that “chemicals are bad” and certainly not to place blame. That would be counterproductive.

Second, we are interested in everyone learning how the innovative technologies that have come out of green and sustainable chemistry may have a positive impact in achieving equity and environmental justice and contribute to a more sustainable chemical enterprise. Next, for educators, we hope to demonstrate how to integrate these topics into the chemistry classroom. Finally, we want to ask what types of research collaborations might be catalyzed by this symposium.

How does the work you do at each of your universities intersect with environmental justice and social equity?

Brush: I am integrating these topics into my green chemistry class, where students examine the links between them and green/sustainable chemistry. I do the same in professional development workshops we offer for middle and high school STEM teachers. In research, my students are examining a diverse community of college students for chemical exposure, and we will look for correlations of exposure to student success.

Lasker: Our health studies program is supported by a mission that incorporates community engagement and social justice with principles of public health and equity. I teach using a systems-thinking approach to health, incorporating green chemistry, environmental health, toxicology, and social determinants of health into all my classes. Scientists have a key role to play in helping achieve global health equity and protecting the health of our planet as well. My work helps bridge both sides—science and public health—toward a common goal of social and environmental justice, starting in the classroom with our future agents of change.

Julie Zimmerman

Photo of Julie Zimmerman.
Credit: Julie Zimmerman

Zimmerman is a professor and senior associate dean of chemical and environmental engineering, forestry, and environmental studies at Yale University. She is also Deputy director for the Yale Center for Green Chemistry & Green Engineering. She focuses on applying green chemistry and engineering principles to the innovative design of products, processes, and systems; assessing benign alternative chemicals and materials; designing and analyzing policy for sustainability, particularly related to water use and corporate environmental behavior; and developing water treatment technologies for developing communities.

What is the meaning of the title of your talk, “Nourishing the Green ChemisTREE”?

In a recent paper (Green Chem. 2018, DOI: 10.1039/c8gc00482j), a team of which I was proud to be a part did a metareview of the field of green chemistry. Using a metaphor that has been used previously—the Petroleum Tree, for example, which shows as its leaves the many products made from crude oil—we constructed the Green ChemisTREE. The twelve “branches” of this tree are the twelve principles of green chemistry. The tree’s leaves are the areas of scientific discovery over the past 20 years since the principles were first published in 1998.

While there have been literally hundreds of reviews within the field of green chemistry, we believe this is the first metareview [an analysis organized by activity within each principle that discusses tools and metrics available, as well as future challenges for the field]. It shows an astounding productivity in terms of scientific discovery that will likely amaze anyone who looks at it. However, taking the metaphor of the tree another step, every tree needs to be nourished, or it will die. Trees need light (awareness and education) and nutrients (funding and diverse perspectives). And no tree is alone in the forest. What are the other trees that interact with and influence the health of the Green ChemisTREE? Green engineering? Toxicology? Policy? Business?

What are the main points you hope attendees take away from your lecture?

The scientific advances—as represented by the leaves—are astounding, but the purpose of a tree is not simply to grow leaves. It’s to enable an ecosystem and a habitat. It’s not our goal just to do science. It’s our goal to enable and empower a sustainable world.

Having a healthy tree and a healthy forest requires more than leaves. Our field requires more than folks just publishing papers. It requires an infrastructure and a community, with some people playing very different roles ranging from communication, to advocacy, to financial investment.

In a 2015 Science editorial you cowrote with Paul Anastas, “Toward Designing Safer Chemicals,” you wrote, “If traditional analyses can be coupled with integrated systems approaches, then the knowledge gained about the nature of complex systems may well lead to the design of chemicals that are compatible with life” (DOI: 10.1126/science.aaa6736). What are the main barriers scientists face today that prevent them from moving past the thinking that “chemical A has consequence B” toward “chemical A has possible consequences across all of system B”?

Most scientists are still trained in reductionism. Reductionism first, last, and always. No wonder—reductionism has transformed the world in the past 200 years and brought about modern life. However, it has also been one big part of bringing about unintended consequences.

Sustainability is a complex nesting of systems in systems that doesn’t lend itself to a reductionist-only approach. Yet we still try to fit the square peg of quantitative metrics into the round hole of sustainability. This is a difficult transition for people to make. People are not used to this. It’s out of their comfort zone. It doesn’t fit with existing models. The experts in the old ways of thinking are not the experts in the new ways of thinking. Intellectual inertia is a bear.

One of your interests is policy design and analysis for sustainability, particularly related to water use and corporate environmental behavior. What kinds of policy design are most effective in influencing corporate environmental behavior?

Just as there needs to be innovation in our science, technology, products, and processes, there also needs to be innovation in our policy and methods of policy-making. In the same way that we need to apply systems thinking to product design and molecular design, we need to apply it to policy design. In that way, the question becomes not, “How do you influence corporate behavior?” but rather, “What is the set of incentives, rewards, and drivers where the interests and desires of corporations, consumers, public health advocates, environmentalists, and the environment are aligned rather than structured as a zero-sum game?”

From your perspective, how have attitudes, both academic and corporate, toward green chemistry and engineering changed in the past decade?

There’s so much green chemistry taking place within business throughout the supply chain that goes unspoken. However, I’m lucky enough to work with a large number of corporations across industry sectors and investors, so I get to see what many people don’t get to see. In business, big companies use green chemistry to do what they’ve always done, but do it better. Small disruptive companies use green chemistry to do a better thing. Those that view the principles of green chemistry and engineering as a system rather than isolated criteria are being far more transformative.

In academia, there are thought leaders and institutional leaders who are now in place to implement the ideals they espoused decades ago. The thought leaders will displace the old guard, but in academia, that’s a slow process because many of the rewards and incentives are a function of the status quo. While I’m never happy with the kinetics of this transformation, I know that intellectual and practical thermodynamics are on our side.


This article has been sent to the following recipient:

Chemistry matters. Join us to get the news you need.