Center for Biological Diversity

For Immediate Release, March 11, 2017

Contact: Nathan Donley, (971) 717-6406,

Court Clears California to Require Cancer Warning on Roundup

FRESNO, Calif.— A court has ruled that the state of California can move forward with plans to designate glyphosate — the main ingredient in Monsanto's widely used herbicide Roundup — as a known carcinogen. The Friday decision, which finalizes a preliminary ruling, sets the stage for the California Environmental Protection Agency to be the first regulatory body in the United States to recognize glyphosate as a carcinogen.

In late 2015 the California agency announced its intent to list glyphosate as a human carcinogen based on the finding by the World Health Organization that it is a “probable” human carcinogen. The WHO's cancer research agency is widely considered to be the gold standard for research on cancer.

“This ruling makes clear that California absolutely made the right decision to move forward in designating Roundup as a carcinogen,” said Nathan Donley, a senior scientist at the Center for Biological Diversity and a former cancer researcher. “This court acknowledged that it's proper for the state to require common-sense labeling that accurately reflects the findings of the world's most reliable, transparent and science-based assessment of glyphosate. Why would you want a lesser standard?”

Monsanto filed a lawsuit challenging the proposed designation soon after the state announced its intent to list glyphosate as a carcinogen under California's Proposition 65 law. In the suit Monsanto alleged that it was unlawful to have an unelected, foreign body inform the state's policies.

“Clearly scientific integrity has nothing to do with political boundaries,” said Donley. “To suggest that the people responsible for protecting California's health and environment should ignore the work of the world's leading researchers is a stark reminder of the dangers of allowing corporate insiders to influence regulation of their own products. Whenever that happens, we all lose.”

Glyphosate is the most widely used pesticide in the United States and the world. It is also the most widely used pesticide in California, as measured by area of treated land. An analysis by the Center found that more than half of the glyphosate sprayed in California is applied in the state's eight most impoverished counties. The analysis also found that the populations in these counties are predominantly Hispanic or Latino, indicating that glyphosate use in California is distributed unequally along both socioeconomic and racial lines.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 1.2 million members and online activists dedicated to the protection of endangered species and wild places.

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