Why is Roundup controversial?

A Press Democrat article published in print April 21, “Napa Green’s Roundup ban underscores controversy behind Sonoma County’s ‘certified sustainable’ vineyards,” has generated a lot of discussion online. Here’s what you need to know about Roundup and its key ingredient glyphosate.

What is glyphosate?

Developed for commercial use by Monsanto in the 1970s, glyphosate is a synthetic herbicide and key ingredient in the weedkiller Roundup.

In 1996, Monsanto began selling “Roundup Ready” crops that were genetically modified to tolerate glyphosate. That meant farmers could spray Roundup without the fear of damaging their crops.

According to a report in the journal Environmental Sciences Europe, glyphosate use has increased nearly 15-fold since Roundup Ready crops were first introduced.

Today, glyphosate is the most widely used herbicide in the U.S. and around the world, where the agriculture industry has embraced it as an effective, low-cost solution to weed control.

In the U.S. wine industry, many growers have used synthetic herbicides like Roundup to control weeds in the vineyard.

In Sonoma County, the California Department of Pesticide Regulation reports 56,847 pounds of glyphosate were applied in 2022 overall, with 40,691 pounds used exclusively in the region’s 60,000 acres of wine grape vineyards.

That’s 47% less than 2014, when 77,754 pounds of glyphosate were applied to wine grapes in Sonoma County.

In Napa County’s 43,000 vineyard acres, 22,561 pounds of glyphosate were applied in 2022.

The controversy

The U.S. Environmental Protection Agency, the European Commission and Roundup manufacturer Monsanto maintain glyphosate and glyphosate-based products like Roundup are safe to use.

But in recent years, Roundup and glyphosate have come under increased scrutiny about their effects on the environment and human health, including its potential link to non-Hodgkin’s lymphoma.

In 2015, the World Health Organization’s International Agency for Research on Cancer cited “strong evidence” that glyphosate is “probably carcinogenic to humans.”

In a landmark case, Dewayne “Lee” Johnson became the first person to win a lawsuit against Monsanto in 2018 for the company neglecting to warn consumers about the dangers of Roundup, which he alleged caused his non-Hodgkin’s lymphoma.

That set a precedent. As of March 2024, Monsanto has reached settlements in nearly 100,000 Roundup lawsuits, paying out an estimated $11 billion, according to the Lawsuit Information Center. While these settlements account for nearly two-thirds of all Roundup claims, the site estimates around 54,000 cases remain.

What do you think about Roundup and glyphosate? Read the full article here and share your comments. If you’re a local winegrower and are trying to make your vineyard more environmentally-friendly, please reach out to us and share what you’re doing.

You can reach Staff Writer Sarah Doyle at 707-521-5478 or sarah.doyle@pressdemocrat.com. Follow Sarah on Instagram at @whiskymuse.