A federal judge has blocked California from requiring that the popular weed-killer Roundup carry warning labels that it is known to cause cancer.
U.S. District Judge William Shubb in Sacramento said in a ruling Monday that the warning is false and misleading because almost all regulators have concluded there is insufficient evidence that Roundup's main ingredient, glyphosate, causes cancer.
Shubb issued a preliminary injunction against the requirement. His order will stay in place while a lawsuit challenging the warning labels continues.
Glyphosate is not restricted by the U.S. Environmental Protection Agency. It has been used widely since 1974 to kill weeds while leaving crops and other plants alive.
California's Office of Environmental Health Hazard Assessment last year added it to a list of chemicals known to cause cancer.
An email to a spokesman for the office was not immediately returned.
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