In 2013, industrial facilities in the U.S. generated approximately 26 billion lb of chemical waste, up 4% from the previous year. Of that amount, 22 billion lb, or 84%, was managed through recycling, treatment, or burning to generate energy. Of the 4 billion lb that was disposed of in the environment, 66% went to landfills or injection wells, 19% was released to air, 10% was transferred to other facilities for disposal, and 5% was released to water.
These data, issued two weeks ago, come from the Environmental Protection Agency’s annual Toxics Release Inventory National Analysis. The data might not seem relevant to the average research chemist or plant engineer. But the numbers reveal that the amount of chemical waste released to land, air, and water has decreased 7% during the past decade, according to EPA’s Daniel H. Teitelbaum, leader of the TRI program’s pollution-prevention team. Furthermore, the releases for some chemicals, including hydrochloric acid, trichloroethylene, and methyl isobutyl ketone, have decreased by more than 60% over that time.
“Those results suggest a real success story in progress,” Teitelbaum says. The EPA team’s analysis points to green chemistry and engineering practices as being behind much of the 7% improvement. “The chemists and chemical engineers and the companies they work for should be getting credit,” he asserts.
For more than two decades, the TRI program has collected standardized information on toxic chemicals manufactured and used and waste generated at more than 20,000 U.S. industrial facilities in mining, electric utility, and chemical sectors. The companies are required to self-report the data and pollution-prevention activities under the Emergency Planning & Community Right-To-Know Act and the Pollution Prevention Act of 1990. They are also encouraged to describe steps they’ve taken to keep chemicals out of the environment through product and manufacturing improvements and waste-management strategies. The ultimate goal of the two laws is to prevent waste from the outset to avoid having to manage it or to clean up pollution after the fact.
Teitelbaum says his team discovered the downward trends because of recent improvements in EPA’s reporting mechanisms. TRI now features an online pollution-prevention search tool that allows facilities to share information about green chemistry and engineering practices, identify barriers to pollution prevention, and estimate the relative effectiveness of different waste-reduction measures.
Industrial chemical manufacturers and users were once hesitant to divulge chemical information for fear of reprisals from environmental groups, consumers, and government regulators. Teitelbaum acknowledges that there’s still a long way to go in curbing waste generation and chemical pollution. But the new TRI reporting has lifted a veil, he says. Companies are becoming more open to transparency in reporting, he notes, as evidenced by a fourfold increase in optional pollution-prevention reports submitted during the past two years.
The additional reporting means information about industry efforts to reduce pollution is more accessible to the public. Anyone can now go to the EPA website and do their own data analyses and check interactive maps by industry sectors and for individual chemicals and companies at state, county, city, and zip code levels. They can compare environmental performance among facilities and companies to see who has done the most to reduce waste per unit of output, implemented preferred waste-management techniques that reduce releases, and lowered their greenhouse gas emissions.
For example, a TRI search of defense contractor BAE Systems reveals that the company has reduced its xylene and zinc releases by about 30% since 2009 at its Southeast Shipyards facility in Mobile, Ala. The company used a combination of selecting less hazardous chemicals, implementing more stringent inventory control to avoid excess storage, and incorporating waste minimization procedures for its metal-surface-coating operations.
In another example, Xerox implemented a solvent recovery system for methyl isobutyl ketone waste in its Webster, N.Y., manufacturing and research facility. Previously, the waste was simply shipped off-site and burned, according to EPA. The reclaimed solvent is now used for cleaning process equipment and in research labs. The facility uses about half the amount of virgin solvent, and the recovered solvent saves Xerox nearly $20 per gal compared with new solvent.
“TRI’s combination of quantitative and qualitative information makes it a valuable resource for tracking environmental progress and identifying sustainable practices,” Teitelbaum says. “TRI reporting is no longer just an obligation, it’s an opportunity to highlight results—a benefit of TRI that previously had gone unrecognized.”
Chemical industry giant DuPont offers yet another example. From 1991 to 2004, DuPont reduced its total TRI waste by 49%, according to company environmental, health, and safety spokeswoman Francesca Dellelci. Since 2004, the company has reduced its total TRI waste by 19%.
Dellelci points to development of DuPont’s insecticide Rynaxypyr as one example of how the company managed to do that. “In addition to designing a safer insecticide, DuPont integrated green chemistry principles into the manufacturing process to minimize, recover, and recycle solvents; minimize waste; and establish inherently safer reaction conditions,” she says. The DuPont scientists who developed Rynaxypyr received the American Chemical Society’s Award for Team Innovation and a Heroes of Chemistry award for those efforts.
“While we have made long-term progress,” Dellelci says, “we continue to focus on driving TRI reductions.”
Most chemical manufacturers such as DuPont now have staff dedicated to exploring green chemistry and incorporating life-cycle analysis to products and manufacturing processes, not just with pollution prevention in mind, but with the company’s bottom line in mind. These companies are not working alone, however. Some of the success can be chalked up to initiatives by nonprofit research organizations.
These groups have created Web-based screening tools such as GreenScreen by Clean Production Action and CleanGredients by GreenBlue that help product designers select environmentally preferred chemicals. Another example is the Tiered Protocol for Endocrine Disruption, a design tool created by a multidisciplinary research team that walks chemists through the process of developing chemicals with inherently low toxicity.
Those resources go hand-in-hand with the EPA Design for the Environment program’s Safer Chemical Ingredients List and the solvent selection guide and process mass intensity calculator developed by the ACS Green Chemistry Institute’s Pharmaceutical Roundtable. The latter is a technical group made up of scientists from pharmaceutical companies with a goal to develop greener versions of common chemical reactions and processes.
It’s no secret that pharmaceutical firms generate the most chemical waste per kilogram of product, a consequence of producing complex molecules of high purity. Drugmakers have claimed that green chemistry practices in manufacturing have significantly reduced the quantities of toxic chemicals they use and release to the environment.
As an exercise, EPA’s Stephen C. DeVito, chief of the TRI program’s Regulatory Development Branch, began exploring how to use the TRI database to verify those claims. That’s when the EPA team discovered that, for the decade 2004–13, TRI quantities reported by the pharmaceutical industry have declined steadily and by about a half.
“These are real, measurable reductions,” DeVito emphasizes, “consistent with implementation of green chemistry practices. They are not being driven by outsourcing, economic trends, other regulations, or shifts in waste-management practices.”
The drug industry’s reductions are largely the result of using less organic solvent, according to the EPA analysis. Methanol, dichloromethane, toluene, dimethylformamide, and acetonitrile account for 75% of the pharma reductions, DeVito says. Pharmaceutical companies are also selecting less hazardous reagents, reducing reaction steps, and developing better catalysts.
Those solvents have definitely come under increased pressure for being volatile organic compounds and/or for their toxicity, says David J. C. Constable, director of the American Chemical Society’s Green Chemistry Institute. Pharma has done a lot to choose better solvents over the past 10 years, Constable notes, although he believes the reductions being highlighted by EPA are still largely process related and not necessarily because the underlying synthetic chemistry has changed significantly.
“The chemistry changes more in second- or third-generation commercial processes,” Constable explains. “It will be then that we can expect to see even greater decreases in wastes, toxics, and emissions.”
The increase in offshoring of drug manufacture, especially in early stages of syntheses, and a shift to larger molecule therapies, such as antibodies, probably do play a role in the U.S. decreases, Constable adds. Despite those uncertainties, “the bottom-line message is that a reduction in toxics release, no matter the cause, is a good reason to celebrate.”
As success breeds success, Teitelbaum says, EPA wants to ensure that TRI will become an even richer pollution-prevention information resource and a source of inspiration for industry and the public. “It’s not just about managing releases anymore,” Teitelbaum says. “It’s about promoting pollution prevention and showcasing your achievements to the public.”