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OKLAHOMA - Roundup is the most popular weed killer on the planet because it works: it kills plants.

The active ingredient in Roundup is a chemical called glyphosate, which is deadly to plants.

The leading seller of glyphosate is Monsanto, the maker of Roundup. Monsanto nets billions a year on their revolutionary biochemical.

"It is the safest herbicide known to agriculture," said Monsanto Vice President of Global Strategy Scott Partridge. "40 years of safe use of glyphosate, not just in the United States but throughout the world."

Farmers use Roundup to control weeds in their fields.

Today, the majority of American growers plant "Roundup ready" crops, which are resistant to the effects of glyphosate.

Growers like Matt Muller plant 'Roundup ready' seed, so they can spray their whole field with glyphosate, but the Roundup targets only the weeds.

"We have GPS technology built into our sprayer that prevents overlap," said Muller, who owns Martha Valley Farms. "It will automatically shut off when we enter areas we've already sprayed."

Muller grows cotton, winter wheat, grain sorghum, mung beans and hay on his 3,000-acre farm near Altus, Oklahoma.

He's been using Roundup since the mid-1990's and believes glyphosate has changed the way American farmers grow their crops.

Because Roundup controls the weeds, farmers no longer need to till their land.

The practice known as "no till" farming conserves moisture in the soil, prevents rainwater run-off and reduces the carbon footprint of the farm.

"Using products such as Roundup have been a great tool in allowing us to be more environmentally responsible in controlling our weeds and not plowing our soil like we used to," Muller said.

Roundup is the most widely used herbicide on the planet.

However, since glyphosate is absorbed into the structure of the plant and the root system, it cannot be washed off.

Lab tests show trace amounts of glyphosate in many processed foods made with Roundup resistant grains.

"If you go test your Cheerios, you'll find glyphosate which is the active ingredient of Roundup," said personal injury lawyer Noble McIntyre. "It's in Cheerios, Pop-Tarts, anything that's a food substance you now have glyphosate in that product."

According to a class-action lawsuit filed in May, an arm of the World Health Organization labeled glyphosate a "probable carcinogen."

"It's this simple: glyphosate is a chemical, it's absorbed into the plant, if you wouldn't put it in a glass and drink it, then you probably don't want it in your food eating it," said McIntyre. "You have to look at what the science says, and the science [is] starting to trend toward this is not something you want in your food if you're wanting to be healthy."

However, according to Monsanto Company spokesperson Charla Lord, it was actually the International Agency for Research on Cancer not the WHO which "classified glyphosate in its Category 2A as a probable carcinogen. This category also includes red meat.

IARC is one of four WHO groups to review information on glyphosate, but it is the only one of the four to come up with this classification.

"ARC is not a regulatory agency. Unlike regulatory reviews that take a comprehensive look at all available data (in the case of glyphosate – 40 years’ worth), IARC makes its conclusion on a limited data review during a meeting that lasts less than a week. No regulatory agency in the world considers glyphosate a carcinogen," Lord said.

Here's a video produced by Monsanto about the safety of glyphosate.

Despite those reassurances, some farmers and many everyday gardeners are concerned Roundup could be killing them.

"I used it probably more than anybody," said Leonard Samuel, who ran a landscaping company in the 1990's.

He never suspected Roundup could be harmful to his health.

"You can't smell it, and if a little bit splashed up on your skin, you don't think anything of it. You just come in and wash off," Samuel said. "There' s nothing (in it) that you say, 'Woooo. I might have to pay for this later.'"

Samuel now has Non-Hodgkin's Lymphoma and he blames Roundup for the disease.

Francene Lisle was diagnosed with Chronic Lymphoma Leukemia in 2016. Her own doctor suggested a connection between her cancer and overexposure to herbicides and pesticides.

"A little light went on in my head because I grew up in a farming community," Lisle said. "I worked at a plant for three years in West Virginia that produced the chemicals for Roundup, actually for Monsanto."

Lisle started treatment earlier this year, and she joined the class-action lawsuit against Monsanto.

"I began to feel a little bit angry, and I realized where all of this came from," Lisle said. "If you'd have known it could have this potential, you would have protected yourself a lot better. I just want for other people not to have to go through this. I want the company to be held accountable."

Lisle eats all organic food now. She wants more protection for consumers and more warnings on bottles of Roundup.

"I want them to be warned. I want them to go out there and read that label and think," said Lisle. "It happened to me, and if I had known, I would not have used Roundup."

Monsanto isn't giving an inch.

"It's not just a little bit of an exaggeration," said Monsanto's Scott Partridge. "It's a little bit of hysteria."

Monsanto is defending their product in court, and in the court of public opinion.

Monsanto has published their own expert research showing Roundup is harmless, less toxic than table salt.

"Glyphosate has been studied for more than forty years of safe use," said Partridge. "There are over 700 medical scientific tests for glyphosate, not one of which has found it to be a cancer-causing agent."

Most of the agricultural community is siding with Monsanto, except for about 1,000 farmers who are suing the company.

"I really feel like the Mountain Dews I drink are causing me more health issues than being around Roundup," said Muller. "Honestly, the American population should be more concerned about sugar and soda pops than about glyphosate."

Farmers like Matt Muller live in their fields. They raise their families in the flight path of the crop dusters.

They are skeptical about a battle waged between lawyers and multi-national companies.

"If we continue to allow emotion and perception and innuendo to drive our farming practices, this country will wake up very hungry someday," Muller said.

Roundup sales have been growing like a weed since the 1970's.

But, a fresh crop of criticism may choke out Monsanto's grip on the global market, especially if this class-action lawsuit puts down roots.

ADDITIONAL INFO:

Learn more about the Roundup litigation

MONSANTO VIDEO: Glyphosate Safety

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