WASHINGTON (Reuters) - The Senate Environment and Public Works Committee on Wednesday approved four nominees to key posts at the Environmental Protection Agency, including one appointee with ties to the chemical industry who will head the agency’s office of chemical safety. Senator Tom Carper, the top Democrat on the committee, said two of the nominees were of “grave concern”: Bill Wehrum, nominated for assistant administrator for the Office of Air and Radiation, and Michael Dourson to head up the Office of Chemical Safety and Pollution Prevention. Carper called Dourson “one of the most troubling nominees I have ever considered during my time on this committee.”  Senator James Inhofe of oil-producing Oklahoma, the panel’s senior Republican, praised the passage of the nominees and urged the full Senate to quickly confirm them so they can “improve public health within the scope of the EPA’s authority.” Republicans say the EPA under former President Barack Obama overstepped its authority to regulate. Scott Pruitt, President Donald Trump’s EPA administrator, has said the agency had an “activist agenda” under former President Barack Obama. Pruitt has worked to do away with regulations pushed through by the Obama administration, and has proposed scrapping the landmark Clean Power Plan that sought to curb emissions linked to climate change. Pruitt sued the agency more than a dozen times when he was Oklahoma’s attorney general.   Jeff Holmstead, a former head of the EPA air and radiation office under former President George W. Bush, said Wehrum is the “ideal person to shepherd Administrator Pruitt’s reforms through the regulatory process.”  Environmentalists called on the full Senate to reject the nominees. “All four of these nominees, especially Wehrum and Dourson, would accelerate Scott Pruitt’s mission to dismantle the EPA from the inside,” said Sara Chieffo, vice president for government affairs at the League of Conservation Voters. The other nominees approved by the panel are Matthew Leopold for assistant administrator for the Office of General Counsel, and David Ross, for the Office of Water. 