SAN JOSE, Calif. (Legal Newsline) -- The expert health witness in a $1 billion public nuisance 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.
Plaintiffs in The People of California v. Atlantic Richfield Company et al. -- 10 cities and counties in California -- have touted Lanphear, who has testified about adverse impacts of lead exposure, as a "premier" expert in lead exposure and public health.
But the defendants in the case -- The Sherwin-Williams Company, NL Industries, ConAgra Grocery Products, DuPont and Atlantic Richfield Company -- attempted to show at trial on Thursday that Lanphear's national studies make broad-based assumptions about California, which, they claim, has some of the lowest levels of child exposure to lead in the country.
The plaintiffs are relying heavily on Lanphear to prove the negative health impacts associated with lead exposure created public nuisance.
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.
Defendants assert that lead-based paint is not as great of a threat or public nuisance as the plaintiffs claim.
Plaintiffs' attorneys say that proving a health risk and threat is "critical" to their case.
"[Lanphear] was testifying about scientific literature that establishes even low levels of lead have very severe negative impacts and that is not a California specific issue. Kids on east coast react the same way," said Owen Clements, chief of special litigation for the city and county of San Francisco.
Pohl was quick to point out that Lanphear, as an epidemiologist, doesn't establish causal relationships.
Pohl and other defense attorneys argue that leaded gasoline was a greater contributor to lead exposure to children, before it was removed from the market around the same time lead-based paint was.
Lanphear did not dispute leaded gas exposures.
He said, "We're left with lead paint and lead in water. But if you took away lead in paint, today, 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."
Both sides agree that nationally, as a policy, blood lead levels that pose a health risk have steadily declined -- from 60 micrograms per deciliter in the 1960s, down to 30 in 1978, then 10 in 1991, then five in 2012. Defendants attribute that success to elimination of lead in gasoline, not paint.
But parties presented conflicting data determining whether children in California on average have higher or lower lead levels.
A defense trial brief quotes a study from the Centers for Disease Control and Prevention Blood Lead Levels in Children Aged 1-5 Years Old - United States, 1999-2010, which has no reference to California blood lead levels and a deposition from the state's Department of Public Health, Childhood Lead Poisoning Prevention Branch Director Valerie Charlton: "Dr. Charlton believes that California children have lower average BLLs [blood lead levels] than the national average and that the incidence of EBLs [elevated blood levels] in California is below the national average."
Plaintiffs quote information from same source, the State Childhood Lead Poisoning Prevention Branch, but no specific study. They also cite a study by expert witness, toxicologist Dr. Paul Mushak, who testified earlier at trial.
Mushak's study, as plaintiffs showed the court, claimed 3.4 percent of children in California have blood lead levels above 4.5 micrograms per deciliter -- higher than the national average of 2.5 percent.
A 2009 CDC report puts California's percentage of children with higher blood lead levels at below 1 percent of children tested.
Defendants don'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, reducing the paint industry's responsibility for lead exposure.
In addition to leaded gasoline, defendants also exhibited a study that Lanphear peer reviewed, which claims lead in water is a leading source of lead exposure, NTP Monograph Health Effects of Low-Level Lead.
Pohl said, "[The report] said primary routes of exposure in the general populations are oral exposure to lead from ingesting contaminated water and food or inhaling air and soil containing lead... This doesn't say paint does it?"
In an attempt to prove that lead in water would expose children to lead levels even if lead based paint were abated from homes, Pohl asked Lanphear if he reviewed whether areas in the study he peer-reviewed had water sources that exceeded EPA water standards, which Lanphear replied he had not.
""You'd still be getting blood levels above 0 as a result of other sources of lead," Pohl said.
Plaintiffs dismissed defendants arguments, as an attempt to shadow the impacts lead based paints have.
"Defendants won't admit scientific truths -- like the tobacco industry," Clements said.
Defendants were quite aware of the harm lead posed, the plaintiffs claim, when the makers and sellers of lead-based paints and pigments promoted them decades ago.
To prove that, the plaintiffs called their third expert witness, Dr. David Rosner, a professor of history at Columbia University and co-author of 11 books, including "Lead Wars," which documents the history of the lead paint industry.
Citing a 1922 Department of Interior survey documenting minerals and resources in use and stock, Rosner said the defendants' current and past paint companies used lead in pigment and paint -- including NL Industries, ConAgra Grocery Products, Du Pont, and Sherwin Williams.
Plaintiffs exhibited a graph from the department that documented the amount of white lead used between 1929-74. The paint industry used the majority of white lead -- nearly 2 million tons of it during that time.
Sherwin-Williams' attorney objected to the testimony stating some defendants stopped using lead in the paint earlier than 1974.
Judge James Kleinberg took note and said more would be revealed in the coming weeks.
Plaintiffs will continue expert testimony of Rosner and possibly another historian next week.
Historically, they must prove the defendants intentionally knew lead paint was dangerous and promoted it in their jurisdictions anyway, which defendants say will be difficult to do.