Chemistry: It's not easy being green
by Katharine Sanderson
Synopsis and resource annotations by Max Grinnell
The environmental reputation of industrial chemistry has not always been
praiseworthy, and folks still remember the Union Carbide pesticide plant
incident or Love Canal, New York and many others. Green chemistry is not
necessarily only concerned with using chemistry to develop green technologies;
it is also concerned with redesigning chemical processes from the ground up to
make industrial chemistry safer, energy-efficient, and essentially green.
This facet of greening chemistry is the subject of an article by Katharine
Sanderson, which appeared in the January 2011 edition of Nature. The article begins by exploring some
of the history behind prominent chemical disasters and discharges, including
the 1984 Union Carbide incident at Bhopal, India which killed over 3,000
people. As a result of this incident, many chemical companies found themselves
responding to more stringent environmental regulations, and the "green
chemistry" movement began.
Paul Anastas coined the term "green chemistry" in 1991 while he was working
for the Environmental Protection Agency. The idea behind greening chemistry is
that chemical processes can, and should, be redesigned to minimize or
eliminate toxic waste from the outset, rather than paying to clean up the
waste later. Anastas remains a fervent advocate of green chemistry, noting,
"It's more efficient, it's more elegant, it's simply better chemistry." Green
chemistry is still very much a work in process, and part of the problem
includes changing hearts and minds, technical limitations, costs, and so on.
The article proceeds to talk a bit about the initial creation of a set of
principles by Anastas and his colleague John Warner that helped define green
chemistry and articulate a set of basic principles. Perhaps not surprisingly,
the pharmaceutical sector has embraced green chemistry, as it has the most to
gain. Part of this gain comes from the decrease in the environmental factor
or "E-factor." Pharmaceutical plants usually generate 25 to 100 kilograms of
waste per kilogram of product, thus there is great room for improving
efficiency through green chemistry. There have been some real successes with
reengineering pharmaceutical processes. For example, Pfizer, the creator of
Viagra, was able to decrease its E-factor from 105 to 8 and also reduce the
E-factor for other drugs including Lyrica from from 86 to 9.
The piece goes on to discuss some of the special challenges faced by
bulk-chemical manufacturers who hope to adopt some of the principles of green
chemistry. These manufacturers deal with products that are produced in larger
volumes than pharmaceuticals, and it is more difficult for these manufacturers
to adopt some of the green principles. This is because their industrial
processes are already highly optimized (with E-factors already between 1 and
5), and it is also difficult to redesign physical plants and production sites
that have a use-life of 30 to 40 years. Other roadblocks to the adoption of
green chemistry are rather thorny technical ones, and they are not without
their own special challenges. Green solvents that have been reengineered after
decades of laboratory work remain less efficient than widely used chlorinated
solvents. And beyond the technical challenges, the way chemists are educated
is also a barrier. They spend all their time learning the chemical process,
but spend little time learning about the larger issues. As chemical
engineering Eric Beckman of the University of Pittsburgh states in the
article, "In the United States, chemists get trained rigorously in chemistry,
but don't see any engineering, product design, or life-cycle analysis."
The piece concludes with a bit of optimism as the reader learns that Anastas,
in his work as the EPA's research chief, continues to spread the
green-chemistry approach at staff meetings at the agency's labs around the
country. His also hopes that the EPA will move from a culture of regulating
and banning to one that promotes designing products that reduce or completely
eliminate the use of hazardous substances from the very beginning of their
Found below is a list of useful resources that will illuminate and enhance
understanding of the topics found within this article.
The first link
first link will take
interested parties to a website from the American Chemical Society where they
will find classroom resources that address green chemistry, such as lesson
plans and lab exercises.
The second link
leads to a number of Interactive Teaching Units on green chemistry created by
the Royal Society of Chemistry.
Moving right along, the
whisk users away to the Greener Education Materials for Chemists site. Here
visitors will find a database of green chemistry materials, including lecture
The fourth link
leads to a creative site from the Environmental Protection Agency (EPA) which
offers software programs that can help students learn about the hazardous
substances in chemical reactions and how to create green synthetic materials
in the laboratory.
The fifth link
to the very authoritative Environmental Chemistry website, which includes
information on green renovation projects and the use of green chemistry in
building sustainable residential and commercial properties.