RALEIGH, N.C. (WNCN) – Worries about a residue of a weed killer in popular breakfast cereals has some concerned about the long-term effects of that substance on those who consume those foods.

Some scientists are concerned the chemical used to protect the grains used to make certain cereals may be in the final product in unsafe levels.

It’s a claim rejected by both the food makers and the maker of the weed killer.

The substance is Glyphosate.

It’s the active ingredient in the weed killer Roundup.

Farmers use Glyphosate to keep crops like corn and other grains from being strangled by weeds that would overtake the fields. 

Here’s the way Glyphosate works.

An entire field gets sprayed, and all plants in the area absorb it.

Weeds take it in and die, while crops like corn don’t die because they are genetically modified so it doesn’t affect them.

Dr. Wes Everman is an extension weed specialist with North Carolina State University and said just 20 ounces of Glyphosate is used to treat an acre of crops.

At those levels he says – it shouldn’t be a problem.

“Typically the Glyphosate we apply would be considered safe,” he says.

But, the Environmental Working Group claims it found what it considers to be excessive levels of the herbicide in such products as Quaker Old Fashioned Oats, Cheerios, Quaker “Dinosaur Egg” Instant Oats, Great Value Instant Oats and Back To Nature Classic Granola Clusters.

“We don’t know a lot about the effects of Glyphosate on children and essentially we’re just kind of throwing it at them,” said Dr. Jennifer Lowry of the American Academy of Pediatrics.

The World Health Organization says Glyphosate is a “probable carcinogen” and the state of California lists it as a chemical “known to the state to cause cancer.”

But, at what levels? 

Monsanto says an adult would have to eat 118 pounds of the food item every day for the rest of their life in order to reach the EPA limit.

“Glyphosate does not cause cancer” and Glyphosate “has a more than 40-year history of safe use,” Monsanto said.

And, Everman says there have been decades of research on the chemical.

‘’There’s a lot of studies that have looked at this, been aggregated, and said these are safe levels,” said Everman. “This is what the current science says.”

Food makers say they rely on government guidelines.

For its part, Quaker Oats says, “Any levels of Glyphosate that may remain are significantly below any limits of the safety standards set by the EPA and the European commission as safe for human consumption.”

And General Mills says, “Our products are safe and without question they meet regulatory safety levels. The EPA has researched this issue and has set rules that we follow.”

Although science is always changing, the EPA currently says the chemical is safe when used as directed.

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