Monsanto Denies Herbicide Cancer Link At Latest Missouri Roundup Trial, Watch Online via CVN

Posted by David Siegel on Sep 15, 2023 1:06:59 PM

Roundup openings-1

CVN screenshot of plaintiff attorney Demetrios Zacharopoulos delivering his opening statement

Clayton, MO - Opening statements in the latest trial accusing agrochemical giant Monsanto’s popular Roundup-brand herbicide of causing cancer took place Wednesday in Missouri state court, and the proceedings are being webcast gavel-to-gavel by Courtroom View Network.

Plaintiff Mark McCostlin claims he developed non-Hodgkins lymphoma in 2017 at the age of 58 due to spraying Roundup in his yard. Lawsuits like McCostlin's maintain Bayer-owned Monsanto knew that glyphosate, a key chemical in Roundup, poses a significant cancer risk but withheld that knowledge from the public to protect sales of a popular product.

Monsanto denies any link between glyphosate exposure and cancer, a strategy that proved successful in seven consecutive prior Roundup trials ending in defense verdicts. The most recent took place in May of last year in the same court and before the same judge as the current case, and that trial was also recorded gavel-to-gavel by CVN.

In his opening statement on behalf of McCostlin, attorney Demetrios Zacharopoulos of Flint Cooper, told jurors that McCostlin and his wife were initially puzzled about about any likely cause for McCostlin’s cancer.

He explained that only after consulting with attorneys in 2019 and learning about the alleged link between glyphosate exposure and his specific type of cancer did he gain a “true appreciation about what truly caused his non-Hodgkin’s lymphoma.”

Representing Monsanto, attorney James Bennett of Dowd Bennett seized on the issue of attorney advertising, arguing it’s driven plaintiffs to file Roundup-related lawsuits based on faulty science.

Monsanto D openings

CVN screenshot of defense attorney James Bennett delivering his opening statement 

Bennett argued scientific studies prove there is no demonstrable link between glyphosate exposure and lymphoma, but that advertising by plaintiff lawyers in the wake of headline-grabbing verdicts in earlier Roundup cases convinced McCostlin to make that connection.

“Those commercials have gone on and on,” Bennett said.

Three of those initial verdicts consisted of $80 million, $289 million and $2 billion awards in California.

However since then and post-Covid, Monsanto has notched seven defense wins before juries in California, Missouri and Oregon.

While the outcome in the McCostlin case will be closely watched, plaintiffs will also have at least two additional opportunities in coming weeks to turn the tide in Roundup litigation. One case is set for trial later this month in San Diego, and another begins in early October in the City of St. Louis.

The current trial in St. Louis County before Judge Brian May is captioned Barbara Allegrezza, et al. v. Monsanto Company, case number 19SL-CC03421 in Missouri’s 21st Judicial Circuit.

E-mail David Siegel at

Topics: Missouri