Electronic-age gizmos ranging from cell phones to computer mice often release enough lead.health and fitness Updated: Mar 05, 2004 20:03 IST
A new study conducted by University of Florida environmental engineers reveals that electronic-age gizmos ranging from cell phones to computer mice often release enough lead in laboratory tests to be classified as hazardous waste under federal Environmental Protection Agency regulations.
The findings could prompt the federal government or individual states to change the disposal rules for millions of tons of electronic devices.
"The bottom line is that when we tested these devices, in many cases they met the EPA definition for regulated hazardous waste," Associate Professor Tim Townsend, the lead investigator on the project,was quoted by Science Daily, as saying.
More than 20 million personal computers became obsolete in 1998 alone, and more than 60 million personal computers are projected to met the same fate in 2005, Townsend said.
In research that began late in 2001, Townsend and four UF graduate students examined cell phones, printers, flat-panel monitors, keyboards, computer mice, remote controls, VCRs, laptops and central processing units, or CPUs.
The e-devices were subjected to a standard EPA testing procedure for hazardous waste called the Toxicity Characteristic Leaching Procedure. It involves mixing the ground-up devices with an acid solution designed to simulate potential conditions in landfills.
The mixture is rotated for 18 hours in a drum container, and the results are tested for eight hazardous metals: mercury, arsenic, cadmium, barium, silver, selenium, chromium and lead.
While smaller devices, such as cell phones could be easily grinded, the task proved difficult for the larger devices such as VCRs, Townsend said.
As a result, a modified version of the test was developed: a sealed 55-gallon drum suspended on an axle connected to a large electric motor.
They placed disassembled printers and other large electronic devices in the drum, added the acid solution and then rotated the contents for 18 hours and tested the leachate.
Every type of electronic device leached lead above the hazardous waste levels in at least some cases, while none of seven other hazardous metals showed up as problems in the tests.
Curiously, the experiments found that computer CPUs frequently exceeded the hazardous waste limit in the modified test, but rarely in the standard test.
On further electrochemical analysis of the solution, it was revealed that the CPUs and other devices containing a large amount of steel tendto leach less lead when the devices were ground up.
"The more steel that you have in a device, the more it tends to diminish the lead that dissolved in the TCLP leachate," Townsend said.
The EPA is in the process of finalizing a rule that will encourage businesses to recycle rather than disposing of television and computer monitors in landfills following the results of the study.
The two-year project is being sponsored by Polk County and the Florida Center for Solid and Hazardous Waste Management, a research center hosted by UF's College of Engineering and funded by the Florida Department of Environmental Protection.
First Published: Mar 05, 2004 20:03 IST