In September 2011, Boren voted in favor of H.R. 2401, a bill that sought to strip the Environmental Protection Agency (EPA) of its ability to regulate air quality in the United States. The Obama Administration threatened to veto the bill, stating that H.R. 2401 would block the implementation of regulations that “would avoid tens of thousands of premature deaths, prevent tens of thousands of heart attacks and thousands of hospital visits for respiratory and cardiovascular disease, and alleviate hundreds of thousands of childhood asthma attacks and other respiratory illnesses.”

According to DirtySecrets.org, Boren has accepted $836,664 in contributions from polluters during his congressional career and has voted for legislation that could put as many as 187,250 lives at risk. No other legislator is considered by DirtySecrets.org to put more lives at risk through his/her votes on environmental bills than Boren.

On September 25, 2005, Boren voted in favor of a House bill to amend the Endangered Species Act of 1973. The legislation sought to prevent the federal government from designating “critical habitat” areas for endangered species. A spokesperson for the Natural Resources Defense Council said of the legislation, “It would be scandalous to pass this bill into law. This legislation would do nothing to protect wildlife and, in fact, would lead to more extinctions. Of the many damaging provisions in this bill, one of the worst would repeal rules that protect endangered species from pesticides like DDT, which nearly killed off the bald eagle years ago. The bill also would fleece U.S. taxpayers by paying wealthy developers to comply with endangered species protections. Under a loose compensation scheme, land developers would be able to name their price for lost profits. In America we don't pay people not to pollute.”