Glyphosate | St. Louis Public Radio

Glyphosate

Monsanto's widely-used weed killer Roundup on a shelf in Home Depot.
File photo | Eli Chen | St. Louis Public Radio

Monsanto and several growers associations filed a federal lawsuit Wednesday against the state of California for adding the herbicide ingredient glyphosate to a list of cancer-causing substances. 

California's Office of Environmental Health Hazard Assessment announced in July it would add glyphosate to Proposition 65. Known as the Safe Drinking Water and Toxic Enforcement Act of 1986, the California law requires the state to publish a list of substances known to cause cancer or reproductive toxicity.

Rici Hoffarth | St. Louis Public Radio

A California law firm has released several dozen internal documents that show that Monsanto influenced research on glyphosate, Roundup’s key ingredient.

The lawyers represent farmers who claimed in a lawsuit that exposure to Roundup caused them non-Hodgkin's lymphoma. The documents posted Tuesday on the law firm's website include email and memos that contain more evidence that the company had ghostwritten research on the health effects of glyphosate. They build on other evidence a federal judge unsealed in March

Monsanto's widely-used weed killer Roundup on a shelf in Home Depot.
File photo | Eli Chen | St. Louis Public Radio

Glyphosate, the active ingredient in Monsanto’s Roundup, will be added to the list of chemicals California warns are known to cause cancer.

The state’s Office of Environmental Health Hazard Assessment has posted a notice on its website that glyphosate will be added to the list on July 7. A California judge denied Monsanto's request to block the state from doing so, but the company has filed an appeal.

Western harvester ants create tunnels in a gel farm in a laboratory at Webster University.
Provided by Webster University

A study at Webster University has revealed that Monsanto's weed killer Roundup can significantly change ant behavior.

Researchers began two years ago to study how ants are affected by man-made contaminants, including Roundup. The product has become controversial recently due to allegations that its key ingredient, glyphosate, causes cancer in humans.

The ant study hasn't been published yet, but student researchers noted that the herbicide significantly affected western harvester ants.

File photo | Carolina Hidalgo | St. Louis Public Radio

The debate over the safety of Monsanto’s weed killer Roundup has become more complicated, as newly released emails suggest the company had ghostwritten scientific research on glyphosate, the pesticide’s key ingredient.

Rachel Heidenry | St. Louis Beacon | File photo

Updated Wednesday, June 29 with statement from Monsanto — Farmers throughout the European Union will continue to use Monsanto's weed killer Roundup, at least for a while.

The European Commission has decided to extend a license that allows glyphosate, a key ingredient in Roundup, to be sold in the European Union for 18 months.

An international panel of scientists reported this week that glyphosate, the main ingredient used in Monsanto's weed killer Roundup is unlikely to cause cancer in humans.

Monsanto Co. filed suit against a California state agency Thursday to keep it from including glyphosate on a list of cancer-causing chemicals.

The California Office of Environmental Health Hazard Assessment said in September it planned to put the herbicide on its Proposition 65 list. That list, created in 1986, includes chemicals known to the state of California to cause cancer.

Glyphosate is a broad-spectrum herbicide that St. Louis-based Monsanto patented in the 1970s under the RoundUp label.