As televisions, computers and monitors and cell phones become disposable commodities to be replaced by newer, more advanced models every few years, the problem becomes what to do with the old ones. The equipment that ends up in landfills can pose environmental hazards if the lead and other toxic materials in them leach into the soil.

A 1999 study published by a University of Florida scientist showed that cathode ray tubes -- or picture tubes -- found in color monitors and TVs leached, on average, more than four times the amount of lead the Environmental Protection Agency defines as hazardous.

Previously companies determined whether their discarded computers should be handled as hazardous. Consumers didn't have to bother with any such regulations. But studies prompted some states to act. Massachusetts was the first to ban all CRTs from landfills, though saving space was more a concern than potential lead leaks.

E-waste is more toxic than normal household rubbish. Computers and other electronic devices contain toxic heavy metals, such as cadmium, lead and mercury. The plastic casing and wiring of computer equipment can also contain hazardous materials. If e-waste is not disposed of in a responsible way, it can seriously harm the environment, wildlife and human health. Landfilling e-waste is not a long term solution because it stores e-waste rather than allows for recovery and reuse of valuable materials.

Unwanted computer equipment that is properly disassembled and recycled can reduce the use of natural resources and prevent hazardous substances from entering the environment. Between 70 and 90 percent of the material in scrap computer equipment (by weight) is potentially recyclable or reusable . For instance, materials such as steel, aluminium, copper, glass and some plastics can be recycled.