SAN JOSE, Calif. (Legal Newsline) -- The expert health witness in a $1 billion public lawsuit against former manufacturers of lead-based paint and pigments never investigated lead exposure specific to California.
"I have not conducted studies that specifically look at or are limited to children in California," epidemiologist Bruce Lanphear testified during a cross-examination Thursday.
The plaintiffs in The People of California v. Atlantic Richfield Company et al. -- 10 cities and counties in California -- touted Lanphear as a "premier" expert in lead exposure and public health. His resume doesn't exactly dispute that.
Lanphear has testified about the adverse impacts lead exposure can have, from developmental disabilities to death.
But the defendants in the case -- The Sherwin-Williams Company, NL Industries, ConAgra Grocery Products, DuPont and Atlantic Richfield Company -- attempted to show Thursday that Lanphear's national studies make broad-based assumptions about California, which has some of the lowest levels of child exposure to lead in the country.
The plaintiffs are relying heavily on Lanphear to prove the health impacts associated with lead exposure.
But, according to his own testimony, Lanphear failed to look at California data and didn't know the average blood lead level in the state.
"If someone suggested there was a massive public health crisis in California, and asked you to comment on it, wouldn't you want to know what those blood lead levels were?" asked Michael Pohl, an attorney for Sherwin-Williams.
Plaintiffs' attorneys argue that proving a health risk and threat is "critical" to their case.
"Defendants won't admit scientific truths -- like the tobacco industry," said Owen Clements, chief of special litigation for the city and county of San Francisco.
The defendants didn't dispute lead's health hazards, but questioned Lanphear's broad-based scientific findings.
They also questioned the science behind allegations that lead-based paint is the primary source of lead exposure.
"If you took away lead-based paint today," Lanphear said during his cross-examination, "my best estimate is that blood lead levels would fall 50 percent. In some communities of color, where children are poorer it would fall even more."
Attorneys for the manufacturers said they seek to prove Lanphear's national average may not apply to California.
They contend children in the state have some of the lowest blood lead levels in the nation, at an average blood lead level of 1 microgram per deciliter -- half the national average of 2-3 micrograms per deciliter.
Next week, plaintiffs are expected to call on a historical expert witness to testify about the history of lead paint and the paint industry.
They must prove the lead-based paint makers intentionally knew lead paint was dangerous and promoted it in their jurisdictions anyway.