Humans began contributing to environmental lead pollution as early as 8,000 years ago, according to a University of Pittsburgh research report.
The Pitt research team detected the oldest-discovered remains of human-derived lead pollution in the world in the northernmost region of Michigan, suggesting metal pollution from mining and other human activities appeared far earlier in North America than in Europe, Asia, and South America. Their findings are highlighted on the cover of the latest issue of Environmental Science & Technology.
"Humanity's environmental legacy spans thousands of years, back to times traditionally associated with hunter-gatherers. Our records indicate that the influence of early Native Americans on the environment can be detected using lake sediments," said David Pompeani, lead author of the research paper and a PhD candidate in Pitt's Department of Geology and Planetary Science. "These findings have important implications for interpreting both the archeological record and environmental history of the upper Great Lakes."
The University of Pittsburgh research team—which included, from Pitt's Department of Geology and Planetary Science, Mark Abbott, associate professor of paleoclimatology, and Daniel Bain, assistant professor of catchment science, along with Pitt alumnus Byron A. Steinman (A&S '11G)—examined Michigan's Keweenaw Peninsula because it is the largest source of pure native copper in North America. Early surveys of the region in the 1800s identified prehistoric human mining activity in the form of such tools as hammerstones, ladders, and pit mines.
The team from the Department of Geology and Planetary Science investigated the timing, location, and magnitude of ancient copper mining pollution. Sediments were collected in June 2010 from three lakes located near ancient mine pits. They analyzed the concentration of lead, titanium, magnesium, iron, and organic matter in the collected sediment cores—finding distinct decade- to century-scale increases in lead pollution preserved from thousands of years ago.
"These data suggest that measurable levels of lead were emitted by preagricultural societies mining copper on Keweenaw Peninsula starting as early as 8,000 years ago," said Pompeani. "Collectively, these records have confirmed, for the first time, that prehistoric pollution from the Michigan Copper Districts can be detected in the sediments found in nearby lakes."
By contrast, reconstructions of metal pollution from other parts of the world, such as Asia, Europe, and South America, only provide evidence for lead pollution during the last 3,000 years, said Pompeani.
"We're hopeful that our work can be used in the future to better understand past environmental changes," said Abbott.
The team is currently investigating places near other prehistoric copper mines surrounding Lake Superior.
The research paper, "Lake Sediments Record Prehistoric Lead Pollution Related to Early Copper Production in North America," was first published online May 14 in Environmental Science and Technology. The work was funded by a Henry Leighton Memorial Fund grant through the University of Pittsburgh Department of Geology and Planetary Science, a graduate student research award from the Geological Society of America, and instrumental support from the National Science Foundation.
B. Rose Huber | EurekAlert!
Preservation of floodplains is flood protection
27.09.2017 | Technische Universität München
Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research