New Roundup Cancer Study Findings Could Delay Litigation

Following the recent publication of a study that questioned whether there was a link between exposure to Roundup and cancer, the U.S. District Judge presiding over the federal litigation is considering whether to delay hearings set for next month to address whether plaintiffs have sufficient evidence to establish general causation. 

There are currently several hundred Roundup lawsuits pending in the federal court system, each raising similar allegations that exposure to the widely used weedkiller caused the development of non-Hodgkins’ lymphoma or other forms of cancer.

Given similar questions of fact and law raised in the litigation, the cases are centralized before U.S. District Judge Vince Chhabria in the Northern District of California, as part of an MDL, or Multidistrict Ligigation.

As part of the coordinated management, Judge Chhabri previously bifurcated the proceedings, indicating that the Court will first address the general causation link between Roundup and cancer, before considering any case-specific issues about whether the weedkiller caused any individual plaintiff’s diagnosis.

The court is currently scheduled to hold Daubert hearings on each side’s challenges to the admissibility of expert witness testimony, and the reliability of studies used by those experts, in December. However, a study published earlier this month in the Journal of the National Cancer Institute may result in that hearing being pushed back to February or March.

The new study used data from the Agricultural Health Study, finding no increased risk of non-Hodgkin’s lymphoma associated with the use of glyphosate, the active ingredient in Roundup weed killer. However, it is the follow-up to a study published several years earlier, which came to the same conclusion.

On November 9, Judge Chhabria issued a pretrial order (PDF) calling for parties to file letter briefs addressing whether the study’s findings raise the need for a continuance of the Daubert hearings set for next month.

In Monsanto’s response (PDF) filed yesterday, the manufacturer argues that the recent publication warrants a delay and erodes the plaintiffs’ case. However, the plaintiffs’ letter (PDF) notes that there is nothing new about the study findings that should delay the hearings, pointing out that the results have already been included in their general causation analysis.

“The November 2017 Article is, in essence, not ‘new.’ As a preliminary matter, the initial 2005 AHS publication and the 2013 AHS draft manuscripts show no positive association between glyphosate use and non-hodgkin’s lymphoma (NHL),” the plaintiffs brief states. “The AHS’s null finding has already been assessed and incorporated in Plaintiffs’ expert analyses.”

The plaintiffs brief notes that they already have an expert witness who has pointed out various flaws in the study, and that it does not outweigh the evidence of a number of epidemiological reports presented by plaintiffs which do, in fact, show the likelihood of a causal link between Roundup exposure and cancer.

Roundup Litigation

The Roundup cancer litigation emerged after the World Health Organization’s International Agency for Research on Cancer (IARC) warned that glyphosate contained in the weedkiller is a probable carcinogen, which was issued in mid-2015.

Since then, a growing number of farmers, landscapers, agricultural workers and others regularly exposed to the herbicide have filed complaints alleging that Monsanto failed to adequately warn that Roundup exposure may increase the risk of cancer.

With Roundup cancer lawyers continuing to review and file new claims, it is ultimately expected that hundreds, if not thousands, of lawsuits will be added to the MDL over the coming months and years.

Following the conclusion of the general causation phase of the litigation, if the cases are not dismissed or Roundup settlements are not reached by the parties, it is expected that Judge Chhabri will establish a “bellwether” program, where a small group of representative cases will be prepared to go to trial. While the outcome of these early cases will not be binding on other plaintiffs, they will be closely watched and monitored, as they may help the parties gauge how juries will respond to certain evidence and testimony that is likely to be repeated throughout the litigation.