U.S. EPA has approved an action removing the solvent ethylene glycol mono-butyl ether (EGBE) from the Clean Air Act's list of hazardous air pollutants, also known as air toxics. EGBE remains on the EPA's list of VOCs that must be reported under the Toxic Release Inventory (TRI). The delisting move, which concludes a lengthy review following a 1997 petition filed by the American Chemistry Council, is being hailed by Dow Chemical Co., a major EGBE producer.

"This is excellent news for our customers," says Mark Bassett, senior Business Commercial leader, Dow Oxygenated Solvents. He says the action will allow wider use of Dow's Butyl Cellosolve solvent, described as the company's "most cost-effective coupling solvent."

Dow representatives say the EPA decision follows a June 15 announcement by the International Agency for Research on Cancer (IARC), which has found "inadequate evidence of carcinogenicity in humans and limited evidence of carcinogenicity in animals" following a study of EGBE's toxicity. The solvent was placed in the IARC's Group 3, or not classifiable as to its carcinogenicity to humans.

In announcing the delisting, EPA representatives say that "after extensively reviewing the levels of EGBE in the air and the health and environmental impacts associated with those levels, EPA has concluded that potential outdoor exposures to EGBE may not reasonably be anticipated to cause human health or environmental problems."

EPA describes the delisting of an air toxic as a rigorous process that involves independent scientific peer review to demonstrate there are adequate data to determine that emissions may not reasonably be anticipated to cause adverse effects. The agency says EGBE's uses include water-based coatings for many applications, varnishes, vinyl and acrylic paints, enamels and spray lacquers.

More information on the delisting, including the final rule and the Federal Register notice when published, is available at www.epa.gov/airlinks/airlinks1.html.

In other EPA news, the agency has announced the signing of a final rule excluding tertiary butyl acetate from the definition of a volatile organic compound (VOC). The rule is expected in the Federal Register shortly.

Houston-based Lyondell Chemical Co.'s tertiary butyl acetate (TBAc), a non-HAP (hazardous air pollutant) organic solvent, is expected to find widespread use in coatings, inks, adhesives, industrial cleaners, photo-resist strippers and other formulated products as a result of the exemption and its versatile properties. According to Lyondell, TBAc offers broad solvency, an intermediate evaporation rate, low density and a flash point well within accepted industry parameters. The solvent's negligible photochemical reactivity prompted Lyondell to petition the EPA for the VOC exemption.

According to Gail Kelly, business development manager, many TBAc-based formulations have been developed in anticipation of the VOC exemption. "The solvent's broad utility and potential regulatory status have created an enormous amount of industry interest," she explains. "We expect to see commercial applications for TBAc almost immediately." With the exemption, TBAc can be substituted for more reactive solvents.