Testing computers' hazardous potential.The standard test to evaluate whether metal-laden products are hazardous fails to flag high concentrations of lead in some discarded electronics equipment, new studies show. "It was a surprise," says Timothy Townsend of the University of Florida University of Florida is the third-largest university in the United States, with 50,912 students (as of Fall 2006) and has the eighth-largest budget (nearly $1.9 billion per year). UF is home to 16 colleges and more than 150 research centers and institutes. in Gainesville. On the other hand, the data are consistent with findings by others for certain metal-foundry wastes, he says. Under the acidic conditions in many landfills, electronic gadgetry gadg·et·ry n. 1. Gadgets considered as a group. 2. The design or construction of gadgets. Noun 1. gadgetry - appliances collectively; "laborsaving gadgetry" can leach lead and, other toxic metals toxic metal Environment Any metal known to be toxic to humans–eg, antimony, arsenic, beryllium, bismuth, cadmium, lead, mercury, nickel. Cf Nontoxic metal. . To test an object's potential to leach metal, federal guidelines require that it be crushed into pieces smaller than 1 cubic centimeter cu·bic centimeter n. Abbr. cc A unit of volume equal to one thousandth (10-3) of a liter or to one milliliter. and soaked for 18 hours in a vinegar-strength acid bath. Products that leach at least 5 milligrams of any toxic metal per liter of solution must be designated as hazardous waste Hazardous waste Any solid, liquid, or gaseous waste materials that, if improperly managed or disposed of, may pose substantial hazards to human health and the environment. Every industrial country in the world has had problems with managing hazardous wastes. when discarded. That usually requires keeping them out of municipal landfills. When Townsend's team conducted this standard test on seven shredded shred n. 1. A long irregular strip that is cut or torn off. 2. A small amount; a particle: not a shred of evidence. tr.v. computer central-processing units (CPUs), none leached enough lead to be deemed hazardous. However, when the group tested dismantled but unshredded CPUs, 9 of 10 failed the acid test. Nine of 30 cathode ray tubes See CRT. (hardware) cathode ray tube - (CRT) An electrical device for displaying images by exciting phosphor dots with a scanned electron beam. CRTs are found in computer VDUs and monitors, televisions and oscilloscopes. from color computer monitors passed the standard shredded-parts test even though separate tests have shown that most of these tubes contain huge amounts of lead (SN: 11/4/00, p. 303). Why didn't the standard test find hazardous amounts of lead in these computer parts? Townsend says it appears to be the products' steel content, which, when shredded, alters the acid bath's chemistry so that it pulls less lead from the shredded parts. Laptop computers contain much less lead than cathode ray tubes do. Nevertheless, six of eight shredded laptops failed the standard test, as did all eight samples of dismantled but unshredded laptops. The laptops' low steel content had little effect on the acid bath, says Townsend. Results for cell phones were similar to those for the laptops. Townsend concludes that for steel-laden electronics, a direct measurement of lead content may be more reliable than the standard leaching test for determining whether the products, when thrown away, should be designated as hazardous waste.--J R. |
|
||||||||||||||||
Printer friendly
Cite/link
Email
Feedback
Reader Opinion