 | Pictured is a 16th-century astrolabe. "The brass in this instrument has been in use for nearly 500 years," says Yale geologist Robert Gordon. "Modern products often serve our needs for a few years or months before discard, jeopardizing the sustainable use of scarce metal resources." |
Researchers studying supplies of copper, zinc and other metals have determined that these finite resources, even if recycled, may not meet the needs of the global population forever, according to a study published in the Proceedings of the National Academy of Sciences.
According to the study, even the full extraction of metals from the Earth's crust and extensive recycling programs may not meet future demand if all nations begin to use the same services enjoyed in developed nations.
The researchers, Robert Gordon and Thomas Graedel of Yale and Marlen Bertram of the Organisation of European Aluminum Refiners, say that the environmental and social consequences of metals depletion became clear after studying metal stocks -- that is, the metal in the Earth, in use by people and lost in landfills -- instead of tracking the flow of metal through the economy in a given time and region.
"There is a direct relation between requisite stock, standard of living and technology in use at a given time," says Gordon, professor of geology and geophysics. "We offer a different approach to studying use of finite resources -- one that is more directly related to environmental concerns than are the discussions found in the economics literature."
Using copper stocks in North America as a starting point, the researchers tracked the evolution of copper mining, use and loss during the 20th century. Then the researchers applied their findings and additional data to an estimate of global demand for copper and other metals if all nations were fully developed and used modern technologies.
According to the study, titled "Metal Stocks and Sustainability," all of the copper in ore, plus all of the copper currently in use, would be required to bring the rest of the world to the level of the developed nations for power transmission, construction and other services and products that depend on copper.
The researchers estimate that 26% of extractable copper in the Earth's crust is now lost in non-recycled wastes; for zinc, it is 19%. Current prices do not reflect those losses, say the researchers, because supplies are still large enough to meet demand, and new methods have helped mines produce material more efficiently.
The study suggests these metals are not at risk of depletion in the immediate future. However, the researchers believe scarce metals, such as platinum, risk depletion in this century because there is no suitable substitute for use in devices such as catalytic converters and hydrogen fuel cells. They also found that, for many metals, the average rate of use per person continues to rise. As a result, the report says, even the more plentiful metals may face similar depletion risks in the future.
"This is looking at recycling on a broader scale," says Cynthia Ekstein, the National Science Foundation (NSF) officer who oversees the funding for the Yale study. "This is looking at the metal lifecycle from cradle to grave."
The research emerged from collaboration among researchers funded by the NSF Biocomplexity in the Environment-- Materials Use: Science, Engineering and Society program.
-- By Janet Retig Emanuel
T H I S
Study: Even with recycling, there's not
enough metal to meet global demand
W E E K ' SS T O R I E S
University launching new program to train tomorrow's journalists
Alliance will boost Yale-BIPI research collaborations
INTERNATIONAL YALE
Yale delegates meet with world leaders at Davos
SOM students learn about India's markets during trips
Faculty member named Young Global LeaderYale honored for design of Farmington Canal site
ENDOWED PROFESSORSHIPS
Derek Briggs named the Beinecke Professor of Geology, Geophysics
Joan Feigenbaum appointed the Henry Ford II Professor . . .
Mark Johnson designated the Kemp Professor of Chemistry
Abraham Silberschatz named the Sidney J. Weinberg Professor . . .Black History Month celebration features talks, performances
Team will study atmospheric 'tsunamis' from on high
Study: Even with recycling, there's not enough metal to meet global demand
Works reveal how humans can 'turn ugliness into music'
Comic Mozart opera proclaims 'Women Are Like That'
Art of adornment is focus of 'Baubles, Bangles and Beads'
Modern art collection takes to the road in gallery's traveling exhibit
Guidelines set standards for doctors' relationships with drug companies
Medications reduce brain changes in youths with bipolar disorder
Study illuminates how the body fights viruses without attacking itself
Use of cell phones by medical personnel cuts rate of error . . .
Six Yale scientists receive awards for their research on aging
Exhibit features magical objects from the Babylonian Collection
Chaplain Frederick J. Streets to be honored as a 'trail blazer'
In Memoriam: A. Dwight Culler, renowned scholar of Victorian literature
Yale BioHaven Entrepreneurship Seminar Series . . .
Yale Books in Brief
Campus Notes
Bulletin Home|Visiting on Campus|Calendar of Events|In the News
Bulletin Board|Classified Ads|Search Archives|Deadlines
Bulletin Staff|Public Affairs|News Releases|
E-Mail Us|Yale Home