Risk Contribution Theory in Lead Exposure Litigation

I found this to be an interesting piece of information because of the potential for widespread impacts with litigation for a wide range of common substances suspected of developmental, behavioral or neurological adverse effects. It has also been interesting in seeing how environmental health issues intersect with the law, as people grapple with finding remedies for problems that, by the nature of epidemiological and environmental health investigative methods, cannot be attributed to specific causes. It’s also been an interesting exercise in reading legal opinions, and trying to navigate around the technicalities to clearly understand and express what they are saying.

The Wisconsin Supreme Court ruled that a 15-year-old boy can sue manufacturers of lead-based paints for his neurological disorders, even though he can’t prove which company manufactured the pigments that he was exposed to. He alleges that the exposures occurred in two houses, built in 1900 and 1905, where he lived as a young child. While he has settled with the owners of the houses, he is still pursuing damages from the manufacturers under the “risk contribution theory of liability”, first adopted in diethylstilbestrol litigation many years ago. In the DES case (Collins vs. Eli Lilly), the plaintiff had vaginal cancer related to her mother taking DES during pregnancy. However, in order to pursue the claim of negligence on the part of the manufacturer, she had to be able to be able to identify the manufacturer or seller of the specific pills taken by her mother, which she was unable to do. In Collins, the court relaxed the plaintiff’s burden to identify the specific manufacturer under the “risk contribution” theory of liability.

Under this theory, the diethylstilbestrol plaintiff needed only to show that a "defendant drug company produced or marketed the type of [diethylstilbestrol] taken by [her] mother" in connection with her claims for both negligence and strict-liability.

Note that the court making the DES ruling didn’t seem to need convincing that the DES exposure was the cause of the plaintiff’s vaginal cancer,

Faced with the certainty that the woman injured by her mother's use of diethylstilbestrol would have no "remedy at law for her injuries" unless the traditional identification-rule was modified. . . Collins relied on article I, section 9 of the Wisconsin Constitution ("Every person is entitled to a certain remedy in the laws for all injuries, or wrongs which he may receive in his person, property, or character."), and decided to "fashion[] a method of recovery for the [diethylstilbestrol] case which will deviate from traditional notions of tort law."

The appeals court declined to apply the risk contribution theory to the Thomas case, however, the case was heard in the Wisconsin Supreme Court. The background for the Supreme Court’s decision was that the companies manufacturing lead-based paints had known about the risks for many years, and had conspired to conceal them. More about that topic can be found in Rosner’s and Markowitz’s book Deceit and Denial, which is discussed further here. The New England Journal of Medicine’s review of Deceit and Denial provides a good introduction to the lead issues addressed in the book.

The legal opinions for this case also mention the “conspiracy” and “enterprise liability” theories – I plan to post on those later.

What’s interesting about this lawsuit is there are several other classes of toxic substances in commerce, where it might be possible that the “risk contribution” theory could apply. These include PBDEs and other fire retardants, PFOA, phthalates and PCBs (not too sure how this would apply to dioxins and furans or mercury, though). If the weight of evidence of adverse human health effects for these substances rises to the level of serious consideration in the courts, we could be hearing more about risk contribution in the future.