WASHINGTON — The House of Representatives has never been less concerned with the environment, a leading environmental organization said Tuesday after scoring congressmen based on their voting records last year.

Led by House Republicans who dismiss environmental regulations as unnecessary job-killers, the House pushed for anti-environmental policies more vigorously last year than it has since the League of Conservation Voters began tracking voting in the ‘70s, said Tiernan Sittenfeld, senior vice president of government affairs.

“In 2011, the House Republican leadership unleashed a truly breathtaking and unprecedented assault on the environment and public health, the breadth and depth of which make the current House of Representatives the most anti-environmental in our nation’s history,” she said.

The League of Conservation Voters scored congressmen on how they voted last year on 11 Senate and 26 House bills deemed the most important environmental legislation of the year. In the aggregate, the scores illustrate a stark partisan divide on environmental policy, with most Democrats earning high scores and most Republicans earning low scores.

With 100 as a perfect pro-environment score, a little more than half of Republican representatives in the House received a score under 10. About seven of every 10 Democrats received a score above 90.

Among Republican leadership, Senate Minority Leader Mitch McConnell scored nine. Speaker of the House John Boehner did not receive a score because as speaker he does not vote consistently, but his average score over his two-decade career in the House was two.

Among Democratic leadership, Senate Majority Leader Harry Reid scored 100 and House Minority Leader Nancy Pelosi scored 89.

The lowest-scoring House Democrats still serving were Rep. Collin Peterson, D-Minn., with a score of 20; Rep. Dan Boren, D-Okla., with 23; and Rep. Mike Ross, D-Ark., with 31.

The top-scoring House Republicans were Rep. Chris Smith, R-N.J., with 60; Rep. Frank LoBiondo, R-N.J., with a score of 54; and Rep. Michael Fitzpatrick, R-Pa., with 46.

Among the bills that the League of Conservation Voters factored into its scoring was last year’s House appropriations bill that included significant cuts in environmental programs. The League considered it “the greatest legislative assault ever on the environment and public health.”

Also included was a bill passed in November that forced the president to make a decision on the controversial Keystone XL pipeline by February, which prompted the administration to reject the pipeline last month.

The group praised Senate Democrats for protecting environmental laws and the president for pushing for stricter standards on power plant pollution, setting new fuel efficiency goals and rejecting the Keystone XL pipeline.

Republicans have said that such environmental regulations burden industries and cost jobs. Some candidates in the Republican presidential primary race, such as Ron Paul and Newt Gingrich, said they would dismantle the Environmental Protection Agency.

Rep. Wally Herger, R-Calif., was pleased with his low score of three.

“I have always opposed the ‘lock it up, let it burn, and don’t-drill-for-oil-in-America’ policies of the extreme environmental movement,” he said in an email. “A low score from the League of Conservation signals that I am doing the right thing for job creation and public safety in the district I represent.”