Conservation advocacy group Friends of the Earth has called on U.S. Environmental Protection Administration chief Christine Todd Whitman to resign, claiming she has lost her credibility both domestically and abroad.
In a letter to Whitman, the group said President Bush's decision to unilaterally remove the United States from the Kyoto climate change treaty negotiations, and White House policy reversals on the regulation of carbon dioxide emissions and arsenic in drinking water are viewed as compromises by Whitman.
"First, the Bush administration destroyed her credibility on climate change. Then, in an astounding blow to public health, Administrator Whitman sent standards for arsenic in drinking water back to 1942," said Friends of the Earth president Brent Blackwelder.
The group urged the former New Jersey governor to step down as a matter of conscience.
There was no immediate response from the EPA.
Whitman's reputation with conservationists has been hurt most severely by Bush's decision to reject a campaign pledge and not take action to reduce carbon emissions from power plants.
Carbon emissions are blamed by many scientists for causing the global atmosphere to warm, resulting in increasingly erratic weather and threatening public health and polar ice cap melting.
Whitman had been telling American allies earlier this year that the administration would seek limits on carbon, but in March, the president said he had changed his mind.
A Department of Energy report detailing the brewing electricity supply crisis out West, and expectations for further supply problems around the country, convinced Bush to reject limits on power plant emissions.
Whitman on Tuesday met with European Union officials, telling them she stood firm with the administration's decision to seek an alternative to the Kyoto treaty.
The pact includes provisions for major industrialized nations to reduce greenhouse gas emissions by an average of 5.2 percent below 1990 levels by 2012.
Bush said the U.S. economy would be harmed by the Kyoto terms, and stressed its inherent unfairness since developing nations like China and India are exempted from the cuts.