"In September 2009, parents, school staff, and politicians were unsettled to learn that children in many U.S. schools are quaffing not just water but lead and other contaminants when they quench their thirst at the school drinking fountain. But the distressing picture painted by the Associated Press analysis of data from the U.S. Environmental Protection Agency (EPA) may be just a small part of a more troubling whole, because the problem of lead in drinking water affects not only schools but homes.
In recent years contamination with lead has emerged as an unintended consequence of water treatment changes aimed at improving water quality. Because lead typically gets into drinking water only after it leaves the water treatment plant, it is difficult to monitor. 'It is impossible to say how common or significant such exposures to lead and other metals are because contamination that occurs within the distribution system isn't monitored," says Rich Valentine, a professor of engineering at the University of Iowa."