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Assault On Asbestos

Congress moves to ban fibrous mineral, and exemption for chlor-alkali makers is not certain

by Cheryl Hogue
March 17, 2008 | A version of this story appeared in Volume 86, Issue 11

Credit: California Department of Conservation
Credit: California Department of Conservation

BANNING ASBESTOS, a known human carcinogen, seems to be a popular cause that nearly every member of Congress can back—especially during an election year. In fact, lawmakers are moving legislation to prohibit sales of this fibrous mineral, but several details of the bill are in flux. Those details could have ramifications for the chemical and construction industries and could even affect sales of some consumer goods.

For instance, when the Senate passed an asbestos ban bill (S. 742) in October 2007, it included an exemption for chlor-alkali plants, some of which use asbestos diaphragms to separate chlorine, caustic soda, and hydrogen. Asbestos materials are used because they hold up well under the harsh chemical conditions in these plants. Alternative materials are available; they reportedly cost more but may last longer.

Chlor-alkali facilities make asbestos diaphragms on-site to custom fit a plant's equipment. Fabrication takes place in a closed room through a wet process, preventing asbestos from becoming airborne and affecting workers. Used diaphragms are removed wet and disposed of as hazardous waste.

It isn't certain whether the Senate bill provision allowing chlor-alkali producers to continue using asbestos will remain in the final version of the legislation. The House Energy & Commerce Committee has drafted, but not yet formally introduced, legislation to ban asbestos that exempts chlor-alkali makers. Both the House draft legislation and S. 742 would require the Environmental Protection Agency to review the exemption every six years.

Labor unions and occupational health experts are asking lawmakers to strike this provision. The exemption for the chlor-alkali plants, they argue, doesn't protect chemical plant workers from exposure to asbestos.

At a Feb. 28 hearing held by the House Energy & Commerce Subcommittee on Environment & Hazardous Materials, Margaret (Peg) Seminario, director of safety and health for the AFL-CIO, said Congress should simply phase out the use of asbestos diaphragms.

Richard A. Lemen, a former assistant surgeon general who is now a consultant in occupational health and safety, agreed. If lawmakers decide to grant chlor-alkali manufacturers an exemption to the asbestos ban, it should last no longer than six years, he said. During those years, the plants should institute strict controls to ensure that workers' exposure to asbestos is at or below the Occupational Safety & Health Administration's permissible exposure limit for the substance, Lemen said.

ALTERNATIVES TO using asbestos in chlor-alkali diaphragms exist, Lemen pointed out to the subcommittee. Two companies, PPG and De Nora, sell materials for making diaphragms that are based on polytetrafluoroethylene (PTFE) fibers.

Some chlor-alkali operations began converting to these nonasbestos diaphragms in the 1990s. PPG, which not only sells PTFE-based diaphragms but also has chlor-alkali facilities, has converted more than half of its facilities that use diaphragms to PTFE-based ones, a company spokeswoman tells C&EN. "It's a viable technology," she says.

But nonasbestos diaphragms may not work well in all facilities, Robert J. Simon, managing director of the American Chemistry Council's Chlorine Chemistry Division, tells C&EN. A 2007 evaluation by the European Commission, the executive branch of the European Union, found that nonasbestos diaphragms are not viable in some chlor-alkali plants, he says. The commission also found that use of asbestos diaphragms does not put workers in the plants at risk, Simon says.

Claims that chlor-alkali workers are at risk from exposure to asbestos "are not accurate," as long as the material is handled properly, Simon says, adding that ACC plans an education campaign on the issue for House lawmakers.

At the hearing, the subcommittee also examined a provision that is in the draft House bill but not in the Senate legislation that could affect some consumer goods.

The House bill would ban "any product, including any part, to which asbestos is deliberately added or used, or in which asbestos is otherwise present in any concentration," said Rep. Albert Wynn (D-Md.), chairman of the subcommittee. On the other hand, S. 742 would ban any product containing 1% or more of asbestos by weight.

Linda Reinstein, executive director of the Asbestos Disease Awareness Organization, told the subcommittee at the hearing that S. 742 "perpetuates a false sense of security" because it does not completely ban asbestos. Reinstein said her group recently analyzed several products for asbestos. For example, she said, they looked at a toy detective kit that contains a fingerprint powder found to contain asbestos. The analysis also found one brand of spackling paste and one type of duct tape to contain the material, she said. The organization has turned over its test results to EPA and the Consumer Product Safety Commission for further action, she added.

Meanwhile, the draft House legislation would also affect stone, sand, and gravel operations and, by extension, the construction industry, which uses these aggregate materials in large quantities. The draft legislation would require the testing of these products and prohibit the sale of the materials if they contain at least 0.25% asbestos by weight.

Rep. John Shadegg (R-Ariz.), the top Republican on the subcommittee, said that this provision might place an onerous requirement on aggregate producers to test each truckload of material leaving a sand or gravel pit for asbestos.

Seminario of the AFL-CIO, however, argued that to protect workers, the legislation should prohibit the sale of aggregate products with any detectable asbestos. Her comments followed testimony by EPA scientists who told the subcommittee that materials containing asbestos at as little as one-thousandth of 1% by weight can cause exposures that lead to disease.

Roger O. McClellan, a consultant and toxicologist who testified at the request of mining companies and builders, said approximately 3 billion tons of sand and gravel are extracted in the U.S. each year. However, only a third of these come from areas of the U.S. where asbestos might be present, he said.

AT THE HEARING, the Bush Administration cautiously indicated that it might back the asbestos ban.

"A legislative approach to address this issue may be one effective way of further reducing the risks from asbestos, provided it is carefully crafted and effectively focuses on actions that will result in risk reduction," said James B. Gulliford, EPA assistant administrator for prevention, pesticides, and toxic substances. He also endorsed provisions in the Senate and draft House bills that would grant exemptions to the ban for the National Aeronautics & Space Administration and the military.

The House is expected to hold more hearings on the asbestos ban legislation in the coming weeks.


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