Organizers may cancel a controversial meeting scheduled for Detroit this Thursday, at which a number of state environmental officials and industry representatives were set to discuss ways that federal environmental regulations could be loosened if George W. Bush wins the presidency. Since news of the gathering was leaked to the press last week, a number of attendees have pulled out. Many of those who had planned to attend have been critical of federal air quality rules and hope the regulatory climate will become more friendly to polluters after President Clinton leaves office. Several of the state officials involved in planning the meeting also have ties to the Bush campaign.