"the change, long sought by chemical manufacturers and fossil fuel companies" "designed to restrict the agency from citing peer-reviewed public-health studies

"the change, long sought by chemical manufacturers and fossil fuel companies" "designed to restrict the agency from citing peer-reviewed public-health studies that use patient medical records that must be kept confidential under patient privacy laws." and the next paragraph: "Such studies include the Harvard School of Public Health’s landmark Six Cities study of 1993, which established links between death rates and dirty air in major U.S. cities. That study was used by EPA to justify tighter air-quality rules opposed by industrial polluters."