Merril Eisenbud said by the mid-1980s he began to doubt the standard he set in 1949 as an Atomic Energy Commission official, partly because he saw about a dozen cases of secretaries contracting chronic beryllium disease.

Eisenbud's 1996 testimony was read Monday in a Jefferson County trial involving four Rocky Flats workers and their wives.

The workers have chronic beryllium disease from handling the metal at the former nuclear weapons plant, and they are suing Cleveland-based Brush Wellman, the world's leading beryllium producer.

They claim the company conspired with the federal government to cover up information showing that the standard failed to protect workers' health.

Some 42 other workers and their spouses also have sued. Their cases hinge on the outcome of this trial, now in its second week.

Eisenbud, who died in 1997, had said he began to change his mind when he started to review cases on the beryllium registry, a database of sick workers. Earlier testimony in the case showed that Brush Wellman did not send its cases to the nationwide registry.

The lawsuit accuses Brush Wellman of censoring medical and scientific information. And evidence introduced in the case shows that the company withheld information about workers who were becoming sick despite exposure levels below the safety standard.