So where do these electronic relics go to retire? Between 2003 and 2005, as much as 85 percent of the disposed electronics in the U.S. went straight in the trash and headed directly to local landfills or incinerators [source: EPA]. Worldwide, as much as 50 million tons of old electronics are discarded annually [source: Carroll].
Some of you may be thinking, "So what? All my other garbage goes to the landfill, why not my old computer?" But let's think back to what we touched on briefly on the previous page -- the potentially lethal chemical combination that could seriously harm the environment if not properly handled.
The dangers of discarded, old computers stem from what's inside them. Your typical piece of electronic equipment -- especially one like a PC with many circuit boards -- may contain up to 8 pounds (3.6 kilograms) of lead, along with lower levels of mercury, arsenic, cadmium, beryllium and other toxic chemicals [source: Downing]. These elements are all toxic at varying exposure levels. There is also a fairly poisonous family of flame-retardant chemicals used in most electronics. Find out how lead affects the body by reading Why do CRTs contain lead?
Many of the aforementioned hazardous chemicals and toxic substances are known to cause health problems -- and in some cases death -- when exposure occurs in large doses. Less is known about the dangers of exposure in small doses over a long period of time, like elevated levels of toxic chemicals in the water supply or inhalation of chemicals by factory workers. It's safe to assume the effects aren't good.
As you may imagine, landfills are a particularly harsh hotbed for pollutants. In the U.S., e-waste accounts for approximately 4 percent of the total amount of trash, but it contributes about 40 percent of the lead content in landfills. Of the other heavy metals in landfills, e-waste accounts for about 70 percent of that pollution [source: Downing]. While most landfills are strategically located in an attempt to contain potential soil and water contamination, having this much hazardous waste on the ground may be cause for concern.
There is an even darker side as to what might await your discarded, old PC. In the U.S., even if you made a well-intentioned effort to properly recycle your computer, there's a 50 to 80 percent chance that your computer didn't end up where you thought it would [source: Ladou]. Continue to the next page to learn more about your ex-computer's potential world tour.