WASHINGTON - Two chairmen of key committees in the House and Senate on Wednesday criticized the White House for editing testimony from a government expert about the health impacts of global warming and demanded documents involving the testimony he provided to Congress. "I am deeply concerned that important scientific and health information was removed from the ... testimony at the last minute," Sen. Barbara Boxer, chairman of the Environment and Public Works Committee, wrote President Bush. Rep. Bart Gordon, D-Tenn., chairman of the House Science and Technology Committee, demanded an explanation from the White House's chief science adviser, John Marburger,...