The digital age's promise to make life easier comes at a cost, with the road to the promise land littered with obsolete electronic equipment - dead monitors, outdated PCs and printers, etc. No ordinary stuff, this is high-tech litter, with harmful chemicals that pose environmental hazards, says an article inArizona Water Resource, a publication produced by the Water Resources Research Center at the University of Arizona. The chemicals and metal by-products of discarded computers can end up contaminating soil, ground water and air.

This is a growing problem. Consider the following: Studies show that in the United States in 1998, about 21 million personal computers became obsolete, with only 2.3 million, or 11 percent, recycled. Experts predict that technological changes will likely result in another 315 million PCs becoming obsolete by 2004.

The component that is one of the worst offenders is the cathode ray tubes, or CRTs, the technical name for the glowing screens used in computer monitors and televisions. The average 14-inch monitor uses a tube containing about 5 to 8 pounds of lead. Dumped in a landfill, this lead can seep into ground water. Crushing or burning the tube can release pollutants into the air.

The Silicon Valley Toxics Coalition (SVTC), a grassroots organization concerned about the environmental and human health problems caused by the electronic industry, provides a lengthy roster of computer pollutants. According to the coalition, modern electronic equipment includes more than 1,000 different materials, including lead and cadmium in computer circuit boards, lead oxide and barium in computer monitors' cathode ray tubes, mercury in switches and flat screens, brominated flame retardants on printed circuit boards, cables and plastic casing, photo-active and biologically active materials, and chromium in the PC's steel exterior.

"Electronic equipment is one of the largest known sources of heavy metals, toxic materials and organic pollutants in municipal trash waste," says Leslie Byster of SVTC.

Legal efforts are underway to control dumping of computer equipment. U.S. Environmental Protection Agency regulations prohibit businesses from dumping computers into the trash. The California Department of Toxic Substances Control considers monitors hazardous waste, and state law prohibits the dumping of computer monitors into landfills.

The European Parliament has taken more extreme measures. A recently passed law requires manufacturers of electrical and electronic equipment to reduce hazardous substances and to pay recycling costs of their products. Almost every electrical item, including personal computer, is included.

Cell phones also pose possible risks to ground water when discarded in landfills since these devices contain many toxic materials, including mercury, cadmium and lead. The increasing number of cell phones will likely cause the problem to become more severe.

Cell phone users tend to upgrade their units every 18 months, with an estimated 40 million cell phones in the United States last year replaced by new and improved versions. The number of cell phone users in the world rapidly is expanding, from about 600 million currently to an expected billion next year. Greater telephone access and convenience, however, come with environmental costs that need to be considered.