According to the National Academy of Sciences, arsenic in drinking water may cause bladder, lung, and skin cancer, harm the nervous system, heart, and blood vessels, and cause birth defects and reproductive problems. Extensive scientific evidence indicates that a maximum allowable level of 50 parts per billion (ppb) for arsenic in tap water does not do enough to protect the public against this potent carcinogen. However, the Environmental Protection Agency's (EPA) standard remained at that level from 1942 until the Clinton administration reduced it to 10 ppb in January 2001.

On March 22, EPA Administrator Christine Whitman suspended the new 10 ppb standard, arguing that it was too strict. Despite the findings of six National Academy of Sciences reports that supported a lower standard, Whitman argued that the rule was not based on "sound science." In September, the Academy issued its seventh arsenic report, which concluded that even the 10 ppb standard presents risks of lung and bladder cancer about 30 times higher than the EPA's "maximum acceptable" cancer risk.

During consideration of H.R. 2620, the VA-HUD and Independent Agencies appropriations bill (which funds the EPA), Representative David Bonior (D-MI) introduced an amendment to prohibit the EPA from delaying or weakening the January 2001 standard of 10 ppb. Environmentalists argued that the 10 ppb standard would protect thousands of Americans from the risk of cancer. On July 27, the House approved the Bonior amendment by a 218-189 vote (House roll call vote 288). YES is the pro-environment vote.

House-Senate conferees later accepted a modified version of the Bonior amendment that would have required EPA to issue a standard no weaker than 10 ppb. In September, just before the conferees reached agreement, EPA Administrator Whitman announced that she would uphold the 10 ppb standard.