YSM Issue 87.2

environmental science
FOCUS
on two variables: availability of the metal and
importance of use.
Reck cited copper as an example. “It would
matter a lot if you didn’t have copper, because
it’s hard to replace copper in electronics,” she
said. “On the other hand, its criticality is still
considered low, because there is a low supply
risk — you find a little bit of copper all over
the world.”
Since the NRC report was published in
2008, the CIE has focused on developing and
analyzing criticality assessments for all metals.
Graedel and his group also extended the
NRC definition to include a third dimension
in addition to supply risk and vulnerability
— environmental implications — to supply
restriction. Any metal element can now be
evaluated in this 3-D “criticality space.”
The CIE’s latest publication has elicited
the most buzz. In a comprehensive study,
Graedel, Reck, and colleagues evaluated how
replaceable each of the 62 metals is for its
major uses. According to their findings, not
a single metal currently has an exceptional
substitute. The best replacement for a metal
would need similar physical and chemical
properties to the metal, but such elements
would likely be found in the same ore deposits
in nature. Thus, the best alternative for a
scarce element would likely be scarce itself.
The Resource Economics Argument
www.yalescientific.org
IMAGE COURTESY OF BUSINESS INSIDER
Behind every smartphone is the dirty
process of mining for rare earth elements.
As a materials scientist with a lifetime of
semiconductor research and a number of
patents, Dr. Tso-Ping Ma is unfazed by this
finding.
“In my field [of microchips], we react
very sensitively to supply and demand,” said
Ma, a former scientist at IBM and now the
Raymond John Wean Professor of Electrical
Engineering and Physics at Yale. “If
something becomes very very rare, people
like us [materials scientists] will look for
something else as good or better.”
Resource economists argue that if
something becomes very scarce, its price
will skyrocket. That high price will then spur
development of substitutes for that material
before society ever grinds to a halt. Thus,
according to this argument, although indium
is rare, we are not in danger of running out
of smartphones or LCD screens, because
increasing costs of indium will force an
indium replacement to be found.
Their argument is not unfounded. A
recent example concerns IKEA, the popular
Swedish company known for its ready-toassemble
home appliances. Many of IKEA’s
kitchen and bathroom products are made of
a stainless steel alloy that, until 2003, included
nickel. However, China’s rapidly growing
appetite for nickel in the early 2000s led to
a spike in the price of the metal, motivating
some nickel users to look for alternatives.
Consequently, in mid-2003, IKEA opted to
completely eliminate nickel from its entire
repertoire of stainless steel products and
switch to ferritic stainless steel — not a
small shift, considering the company’s annual
consumption of stainless steel in 2007 was
around 60,000 tons.
In this age where virtually every element in
the periodic table is used, IKEA and other
forward-looking companies are focusing more
on element scarcity in addition to product
performance in their business decisions. “It’s
a materials gamble,” said Ma.
Seeking Sustainability
If the supply of materials were more
sustainable, this gamble could be less risky —
one reason why scientists strongly advocate
metal recycling. The goal is to achieve a
closed-loop system where all materials are
reused, thus creating zero waste. For example,
lead use in batteries is nearly a closed-loop
system; an estimated 90 to 95 percent of lead
is collected and pre-processed from batteries.
In contrast, only 5 to 10 percent of electronics’
platinum group metals are recycled.
Reck pinpointed two prime ways to improve
metal recycling. The first is simple: Improve
collection. This applies to metals that are
easy to identify and reprocess, like iron and
copper, as well as to specialty metals that are
used in tiny quantities in many consumer
goods. Improving collection of these metals
is especially important because many of them
are used in electronic devices with short
lifetimes and are currently not recycled at all.
The second challenge is to design products
with recycling in mind. Today’s products
are designed using diverse combinations of
metals that make them more functional than
ever before. However, this also means it is
a lot harder to separate these metals from a
mixture; rare earth elements are particularly
tricky because they share many similar
properties. Furthermore, some metals, if
not separated properly, can be disastrous
impurities — an expensive waste of both
scarce and common metals.
So are we actually running out of metals?
Experts at the Yale CIE cautiously say “not
exactly” while emphasizing the importance
of sustainability and offering a more nuanced
perspective as their answer.
“A more insightful question is to ask whether
supplies will be sufficiently constrained to
impede routine industrial use,” Graedel wrote
in a review for the MRS Bulletin. “There, our
conclusions are on shakier ground.”
ABOUT THE AUTHOR
RENEE WU
RENEE WU is a senior Molecular, Cellular, & Developmental Biology major in
Silliman College. She is the former Managing Editor and Features Editor for the
Yale Scientific and works in Dr. Eric Meffre’s lab studying B cell development in
humans.
THE AUTHOR WOULD LIKE TO THANK Dr. Reck and Professor Ma for their time
and enthusiasm.
FURTHER READING
Greenfield, A., & Graedel, T. E. (2013). The omnivorous diet of modern technology.
Resources, Conservation and Recycling, 74(0), 1-7.
March 2014
Yale Scientific Magazine
17