[EPA press release - May 31, 1977]

Environmental Protection Agency Administrator Douglas M. Costle today "listed" the organic chemical "benzene" as a hazardous air pollutant, based on scientific reports strongly suggesting that humans exposed to this substance suffer an increased incidence of leukemia. "Listing" is the first step in regulating benzene under the Clean Air Act.

"EPA will begin a thorough review of current scientific data to determine the health risks from benzene in the ambient (outside) air," Costle said. "After this health risks assessment is completed, EPA will decide which sources of benzene emissions must be controlled, and the extent of control needed." Costle said EPA will work closely with the Occupational Safety and Health Administration (OSHA) to assure that the agencies' regulations are compatible and that the health of the public is protected.

Dr. Eula Bingham, Assistant Secretary of Labor for Occupational Safety and Health, said "The EPA action is a welcome addition to our recent efforts to reduce workplace exposure to benzene. Our emergency standard and our proposed permanent standard raise the issue of worker exposure in places where public exposure is also potentially harmful. The ambient air studies should prove very helpful."

Scientific reports have established that an increased incidence of leukemia occurs in workers exposed to benzene. These data include an April 1977 National Institute of Occupational Safety and Health Administration study indicating high levels of leukemia in exposed workers. OSHA moved to reduce allowable work place exposure levels.

Benzene is one of the largest volume chemicals produced in the U.S., and is used in a wide variety of chemical and industrial processes. It is also an ingredient in automobile gasoline. Of 11 billion pounds manufactured in 1976, as much as 260 million pounds may have been emitted to the atmosphere. These emissions come from chemical manufacturing facilities, petroleum refineries, gasoline storage handling and marketing facilities, coke ovens and automobiles.

"A large number of Americans could be exposed to measurable concentrations of benzene in the ambient air," Costle said, "and while these ambient levels are substantially lower than those affecting workers, there is reason to believe that ambient exposures may constitute a cancer risk and should be reduced.

"EPA's regulatory policy recognizes that some risk exists at any level of exposure to carcinogenic chemicals," Costle said. "Under this policy, emissions and resultant ambient concentrations should be reduced to the lowest possible level. In making a judgment on the degree of control which can and should be required for benzene, EPA will consider the availability of control technology and the relative risk to the public before and after emission controls are employed."

The law requires that within six months of today's listing, EPA must issue proposed standards for benzene and hold a public hearing on the proposal soon after that. Not later than six months after proposal, the Agency must issue final standards for benzene--unless the Administrator determines on the basis of public comment that the pollutant is not hazardous.

"However, recent EPA experience in developing and promulgating regulations to control vinyl chloride emissions indicates that this schedule may not be feasible," Costle said. "Completion of the health risk assessment is essential before a responsible determination can be made as to which sources of benzene emissions must be controlled, and the extent of control needed. EPA has tentatively concluded that emission reductions from some chemical manufacturing facilities, petroleum refineries, and coke ovens may be necessary. Work already in process to develop data on adequate control technology for these sources is being expanded to permit the proposal of emission control regulations as soon as possible after completion of the risk assessment."

EPA already has hazardous air pollutant regulations in effect for vinyl choride, asbestos, berryllium and mercury.