No one can reasonably argue against last week's government order banning almost all uses of cancer-causing asbestos. The substance has been identified for years as a serious health hazard. But one can question why the ban - debated for 10 years - took so long to be applied.

Hundreds of products are affected by the prohibition. They range from auto brake parts to construction materials to water pipes. The ban will be phased in over the next seven years and will apply only to new products.The cost of changing from asbestos products to substitutes is estimated at $460 million spread over 13 years. That is an acceptable figure to produce an essentially asbestos-free environment.

Older products containing asbestos - those items that have not been previously prohibited - will not have to be replaced.

"Disturbing asbestos brakes, shingles or siding already in place where there is no health or safety reason to do so can cause a much greater health hazard than leaving them in place," says EPA chief William Reilly. That is a sensible approach.

However, the cleanup of asbestos insulation, including any in the nation's schools, will continue unabated. Loose asbestos insulation or spray-on asbestos have both been banned from production since 1978. Congress has ordered both to be removed from all buildings.

In recent years, the use of asbestos has declined sharply as concern about health hazards have spread. Major asbestos producers have been forced into bankruptcy or near-bankruptcy because of lawsuits. The biggest use is in automobiles as brake pads and liners.

Reilly, the new EPA chief, says his first question in the new job was: "Why has this thing been around so long?" His quick action in getting the asbestos ban in effect is a signal that the Bush administration is serious about environmental concerns.