In December, Federal Rule of Evidence 702, the federal statutory law governing expert witness opinion's admissibility, changed. This change was made to emphasize “[E]ach expert opinion must stay within the bounds of what can be concluded from a reliable application of the expert’s basis and methodology.” This will have profound implications for mass tort cases that rely heavily on scientific evidence and the testimony of expert witnesses.
The Advisory Committee responsible for drafting and proposing this new rule noted that the change reflects the broad consensus developed over the last five years of meetings that Rule 702 has been improvidently applied in many cases. The new emphasis on limiting expert testimony to its scientific basis and methodology will alter mass tort cases that rely on scientific evidence and testimony, such as the billion-dollar tort settlements reached by Johnson & Johnson during the onslaught of litigation surrounding its talc-based baby powder.
Talc Litigation
One must hope that a stronger application of ‘Rule 702,’ combined with the findings of a newly published systematic review, will reframe the assessment of experts and evidence in future talc litigation.
In talc litigation regarding female reproductive cancers, the claimants’ approach has been historically simple and simplistic. Talc is a naturally occurring mineral which, in some localities, contains so-called asbestiform minerals. There is actually no mineral called asbestos; it is a name used for six different minerals that can occur in fibrous form.
Most mineral fibers have length-to-width ratios in the thousands. At some point, when the federal government needed to set regulations controlling workplace exposures to asbestos minerals, it invoked a precautionary principle definition of a ‘fiber’ as anything that has an aspect ratio of three or greater.
Because talc with minor amounts of asbestos or asbestiform minerals are found together in nature, talc removed from mines and quarries can sometimes contain tiny amounts of minerals that could be called ‘asbestos’ under federal occupational regulations. According to the American Cancer Society, however, talc-based consumer products have been free of asbestos at detectable levels in the U.S. since the 1970s.
Most of the personal injury lawsuits for cancer are based on a claim that there were asbestos minerals found in consumer talc. Asbestos is a known carcinogen. Talc, however, is not.
Putting aside the hyperbolic claims made in litigation, consumers also worry about using talc due to a widely circulated statement made by the International Agency for Research on Cancer, which claims that genitally applying talc-based powder is “possibly carcinogenic to humans.”
These are the claims. But where is the evidence?
A new systematic review published in Frontiers in Toxicology says we have nowhere near the amount or quality of evidence to make causal claims about personal talc use. In fact, the sheer lack of evidence would shock those who have been following the issue as it unfolds.
The review was completed by a team at Stantec that included highly qualified toxicologists and epidemiologists and was funded by the Center for Truth in Science, of which I have a seat on the board of directors. [1] It assessed the quality of the existing, published studies on possible associations between talcum powder use and ovarian, endometrial, and cervical cancers. Amazingly, this systematic review is the first of its kind for talcum powder, a multi-billion dollar elephant sitting at the intersection of science, justice, and the economy.
In this review, the literature search and selection process identified 40 primary studies; 31 were focused on ovarian cancer. There were few high-quality studies for ovarian cancer, but even the better-quality studies did not support any kind of causal connection with talcum powder.
Case-control studies comparing two groups of women (one with ovarian cancer and one without) found inconsistent or no associations. Eleven were rated low or medium quality because they required women to self-reported talc use retroactively over decades. Such retrospective studies are prone to recall bias because persons with the disease outcome recall past use differently from those without the disease. The cohort studies, which the Stantec team rated of medium quality, did not show an association between talc use and ovarian cancer. Looking at the entire evidentiary display, the Stantec team concluded there is suggestive evidence of no association between talcum powder use and ovarian cancer. They found the same for endometrial cancer, although the total amount of research on this type of cancer was much smaller than what was available for ovarian cancer. Evidence was insufficient to conclude any association with cervical cancer.
Thus, the litigation over talc and ovarian cancers trades on some heavily simplistic extrapolations. While some epidemiologic studies show associations between occupational exposures to some kinds of asbestos and ovarian cancer in women workers, many of these studies included cases diagnosed before ovarian cancers were reliably and accurately distinguished from peritoneal mesothelioma, which is a known consequence of heavy asbestos exposure.
Hopefully, the Stantec review, in the light of the new governing law, will help courts take a fresh look at the opinions of previous and future expert witnesses who make causal claims based upon dubious extrapolations. Additionally, members of the scientific community should temper their judgments of causality with epistemic humility and with the knowledge that improvident claims of ‘links’ and causality only scare people and waste court resources.
For decades, millions of people, especially women, have been applying talc-based products for personal hygiene reasons. Decisions like the J&J lawsuits that impact the lives and livelihoods of millions of people should be made using robust, valid, complete, and accurate science.
In making bold claims, expert scientific witnesses must provide strong and sufficient evidence to support and show their work. The new Rule 702 will require at least this much.
[1] Stantec is a global design and consulting firm providing architecture, engineering, construction, and environmental sciences services. The Center for Truth in Sciences is an organization dedicated to seeking integrity in the pursuit of scientific knowledge. The entire review was conducted independently from the Center, which maintains a strict hands-off policy on all research initiatives.
Nathan Schachtman is an active lawyer serving of Counsel, to Ulmer & Berne, LLP, with over forty years of experience with health effects litigation. He does not represent any company in the current consumer talc litigation. Jacob Traverse MBA, MMB is the President & CEO of the Center for Truth in Science