Jim Hughes, a plaintiffs' attorney with Motley Rice LLC in Mount Pleasant, S.C., currently has 193 silica cases in the discovery phase. Mr. Hughes believes that silica litigation nationwide will go up because more and more people are being diagnosed with silica-related diseases.

"The number of deaths from silica-related diseases is going down, but the number of cases filed will not go down," said Mr. Hughes. "Before, doctors and radiologists didn't know to look for silica-related diseases. Now they do."

But Mark Behrens, an attorney with defense firm Shook, Hardy & Bacon L.L.P. in Washington, D.C., thinks that the increase in claimants is due more to aggressive recruitment by the plaintiffs' bar than to an increase in injuries.

Mr. Behrens is also counsel to the Coalition for Litigation Justice, an insurer group seeking fairness in the silica adjudication and settlement process. The coalition includes CNA, Chubb, Hartford, Fireman's Fund, and ACE, among others.

"The plaintiffs' bar is diversifying its portfolio," noted Mr. Behrens. "They thought that the federal asbestos bill and state tort reforms might take away their asbestos cases, so they turned to silica. They became worried about having all their eggs in one basket."

"In some instances, firms started recycling their asbestos plaintiffs, bringing silica actions on behalf of people who had already litigated or settled asbestos claims," Mr. Behrens added. "The plaintiff firms had the mechanisms in place for recruiting silica plaintiffs, who often came from the same types of industries as asbestos claimants. They also had the medical experts and X-ray machines and screening vans in place."

Mr. Hughes countered that the injuries are real and that many suppliers were negligent in failing to warn of the dangers of silica.

Scoffing at plaintiffs' failure-to-warn allegations, Mr. Behrens pointed out that, unlike asbestos dangers, "silica hazards have been well known since the turn of the century."

But according to Mr. Hughes, the fact that silica dangers have long been known in medical science, and in the silica industry, does not negate the suppliers' duty to warn those who might not know about the potential dangers.

One thing that Mr. Hughes and Mr. Behrens seem to agree on is that silica will not cause an asbestos-like litigation explosion.

"In many industries with silica exposure, such as quarries and rock-cutting, there are no third-party defendants to go after," Mr. Hughes noted. "So those claimants would be limited to workers' compensation benefits."

Mr. Behrens sees companies' defenses as being the main bar to a proliferation of suits. "If the courts apply established tort law, the cases won't succeed," he said.

Mr. Behrens explained that, under the "bulk supplier doctrine," once the silica supplier provides warnings to the employers?through labels or other means?it is the employers' duty to convey those warnings to its employees.

"Or the supplier could say that the employer already knew of the dangers, so there was no duty to warn someone that already knew," Mr. Behrens added.

Even if the employer failed to warn, its liability would probably be limited to workers' comp benefits, Mr. Behrens pointed out. "Claimants generally want to go outside of the comp system so they can collect punitive damages and for their pain and suffering," he noted.