On Oct. 15, chemists dedicated to reducing their field’s environmental footprint converged on a Washington, D.C., auditorium across the street from the American Chemical Society for the 2018 Green Chemistry Challenge Awards ceremony. The prizes honored streamlined routes to HIV medications, a technology that eliminates a toxic gas from production of plastic feedstocks, a process for extracting a valuable biodegradable polymer from crustaceans, and a new herbicide designed to minimize agricultural workers’ exposure.
“These groundbreaking contributions reinforce the notion that green chemistry is smart chemistry and raise the bar for all companies and innovators to strive for sustainable solutions,” says GreenCentre Canada interim executive director Lynne Manuel, who was not involved in the awards.
Two winners optimized manufacturing processes for HIV drugs. For its synthesis of doravirine, which the U.S. Food & Drug Administration approved in August, Merck Research Laboratories took home the Greener Synthetic Pathways Award for the second consecutive year. Meanwhile, Frank Gupton and Tyler McQuade of Virginia Commonwealth University won the Academic Award for their route to nevirapine, a key component of combination drug therapies for HIV.
By using a common solvent for several transformations, the teams avoided multiple intermediate isolations and increased their chemical yields, says Jason Cooke, scientific leader for a chemistry team developing an HIV drug candidate at GlaxoSmithKline. Continuous processing allowed the awardees to use hazardous materials safely and to avoid energy-intensive temperature extremes, he adds. “In both cases, the environmentally sustainable processes that were developed were also more economically attractive, which allowed a significant reduction in the cost of the drug.”
Chemetry won the Small Business Award for its eShuttle technology, an electrochemistry innovation that eliminates chlorine gas in the production of both propylene chlorohydrin, a precursor to the polyurethanes used in applications such as foam seat cushions, and ethylene dichloride, a precursor to the polyvinyl chloride found in flooring and raincoats. The Chemetry process uses lower electrochemical cell voltages than those used by the traditional process, thus reducing power consumption and associated carbon emissions, says Marianne Asaro, director of chemistry and catalysis at consulting firm IHS Markit.
Mari Signum earned the Greener Reaction Conditions Award for its process that extracts chitin, a biodegradable polymer, from shrimp shell waste. The natural biopolymer and its derivative chitosan are in demand for biomedical applications, explains chitin expert Marguerite Rinaudo of Grenoble Alpes University. Traditional chitin isolation requires harsh treatments with HCl and NaOH, whereas Mari Signum’s technique employs a recyclable ionic liquid.
Finally, the Design of Greener Chemicals Award went to DowDuPont spin-off Corteva Agriscience for a new weed killer, Rinskor, made for use with rice. According to Corteva’s analysis, Rinskor requires less active ingredient per acre of crop to kill weeds effectively than competing products. Rinskor “epitomizes what an environmentally friendlier pesticide should be,” says weed scientist Franck Dayan at Colorado State University. “Its mechanism of action is unique to plants, making it particularly safe to the ecosystem.”
The awards program touts the environmental and economic benefits of green chemistry and incentivizes green practices in line with the goals of the U.S. Pollution Prevention Act of 1990. The prizes got their start in 1996 after the U.S. Environmental Protection Agency received funding from then-president Bill Clinton. In 2017, the name changed from “Presidential Green Chemistry Challenge Awards” to “Green Chemistry Challenge Awards.” The ACS Green Chemistry Institute (ACS GCI) has historically collaborated with EPA to manage the awards. For 2018, ACS GCI managed the program in its entirety. “We hope EPA will be returning for the 2019 award cycle,” says ACS GCI Director Mary Kirchhoff. ACS is the publisher of C&EN.
“It’s definitely not a good sign in terms of how the country prioritizes clean air, water, and soil when EPA isn’t [involved with] the award and the presidential designation is removed,” says Swiss Federal Institute of Technology (ETH), Zurich, environmental chemist Kristopher McNeill.
EPA was unable to commit to the 2018 awards cycle because the agency did not have long-term certainty about the program’s financial situation, according to an EPA spokesperson. The agency is considering options for participation in the 2019 awards cycle; appropriations for the remainder of the 2019 fiscal year will inform whether the agency has funds and authorization for all activities associated with the awards, the spokesperson says. In fiscal year 2015, the awards program was allocated between $80,000 and $90,000 of the EPA Pollution Prevention Program’s $13.9 million proposed budget, according to a report by EPA’s Office of Inspector General.