U.S. petrochemical plants pose security risks to millions of Americans and could be targets of terrorist attacks, but the government has no idea how secure the plants are from such attacks, according to an audit released last week by the General Accounting Office. The audit found that both U.S. EPA Administrator Christie Whitman and Homeland Security Secretary Tom Ridge want the chemical industry to be required to take stock of any vulnerabilities and ramp up security to address them; however, the two officials appear to be holding back on proposing new regulations mandating such changes because of industry threats of litigation. Last year, lobbyists killed a bill in the Senate, sponsored by Sen. Jon Corzine (D-N.J.), that would have required the chemical industry to beef up security measures.