A 2019 report suggests that certain beers and wines contain traces of a weed-killing chemical.

The chemical in question, known as glyphosate, has been tentatively linked to cancer, though many scientists argue that the evidence isn't conclusive.

The researchers tested 20 samples of beer and wine, including popular brands like Coors, Sutter Home, and Budweiser.

Their results showed lower levels of glyphosate in these beverages compared to previous tests of other food products.

Thousands of plaintiffs have filed claims against Monsanto (now part of Bayer), arguing that the company's popular herbicide, Roundup, contributed to their cancer diagnoses.

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The list of foods known to contain traces of a popular weed-killer continues to grow.

In 2018, the nonprofit Environmental Working Group (EWG) discovered traces of glyphosate, the most widely used agricultural pesticide in the world, in dozens of Quaker, Kellogg's, and General Mills products, including cereals like Cheerios and Lucky Charms.

Less than a year later, another report suggested that certain beers and wines contain the same chemical, which some researchers have linked to cancer.

Read more: There's a chemical in coffee that may cause cancer, but researchers have found a way to reduce your risk

In August 2018, a judge ordered Monsanto (now part of Bayer) to pay $78.6 million in damages to a groundskeeper who attributed his cancer to Roundup, the company's popular herbicide, which uses glyphosate as the active ingredient.

The groundskeeper is among thousands of plaintiffs who have filed similar claims.

On March 19, a federal jury ruled that Roundup was a "substantial" contributor to a man's cancer diagnosis in 2015. After using the weed-killer to tend his property for more than two decades, 70-year-old Edwin Hardeman said Roundup caused his non-Hodgkin's lymphoma.

Most recently, a California jury ordered Monsanto to pay $2 billion in damages to a husband and wife, Alva and Alberta Pilliod, who each developed non-Hodgkin lymphoma after using Roundup for 35 years. In a statement, Bayer said it would appeal the verdict.

"We have great sympathy for Mr. and Mrs. Pilliod, but the evidence in this case was clear that both have long histories of illnesses known to be substantial risk factors for non-Hodgkin's lymphoma," the company said in a statement.

As lawsuits like these move forward in court, researchers have begun to dig further into the potential risk of consuming traces of glyphosate in foods and drinks.

In February, the US Public Interest Research Group (US PIRG) tested 20 alcoholic beverages — five wines and 15 beers — for glyphosate. All but one product tested positive for the chemical, though the amounts varied.

The findings could have implications for major brands like Coors, Sutter Home, and Budweiser, but consumers shouldn't panic just yet. When it comes to chemicals like glyphosate, the dose makes the poison.

Does glyphosate cause cancer?

The link between glyphosate and cancer is tentative.

Much of the concern surrounding the chemical boils down to a report published by the WHO's International Agency for Research on Cancer, which said the herbicide was "probably carcinogenic in humans." Reuters later reviewed the material and found that the IARC had edited parts of the document that didn't align with its conclusion.

An environmental exposure professor at Harvard previously told Business Insider that the IARC was "world-renowned and reputable" institution whose findings had benefited global cancer researchers.

But many scientific institutions disagree that glyphosate should be labeled a carcinogen.

Monsanto's Roundup weed-killer on display at a garden shop near Paris. Thomson Reuters

Organizations like the Environmental Protection Agency, the European Commission, Canada's Pest Management Regulatory Agency, and the World Health Organization's International Program on Chemical Safety, have all stated that glyphosate does not present a public health concern.

As with any chemical, consuming glyphosate in excess could pose a health hazard. But there's been much debate over how much glyphosate is "safe" to eat or drink.

The EPA's safety limits for glyphosate vary based on the food. For a 154-pound adult, the organization generally considers up to 140 daily milligrams safe for consumption.

This level is much higher than the one outlined by the Environmental Working Group, which suggests no more than 0.01 milligrams per day is healthy. Consuming this small dose equates to a one-in-a-million cancer risk in children, and an even lower risk among adults.

In 2017, a study published in the Journal of Epidemiology and Public Health found enough evidence to suggest that the EPA's safety standards for glyphosate were "outdated and may fail to protect public health or the environment." The study argued that it could be time for the EPA to reassess its criteria.

Are beer and wine safe to drink?

Recent tests indicate that beer and wine contain much lower traces of glyphosate than the cereals, cookies, and overnight oats tested by EWG.

Coors Light contained 31 parts per billion of glyphosate. REUTERS/Rick Wilking

Of all the alcoholic beverages studied in the US PIRG report, the beverage with the highest amount of glyphosate was Sutter Home merlot, which contained just over 50 parts per billion.

To put that into perspective, Quaker Overnight Oats have been found to contain upwards of 1,000 parts per billion, or around 20 times the amount of glyphosate.

A toxicologist for Bayer told USA Today that a 125-pound adult would have to consume 308 gallons of Sutter Home merlot per day over their lifetime to reach the EPA's exposure limit.

Other wines like Barefoot Cabernet Sauvignon and Beringer Estates Moscato contained slightly lower levels of glyphosate, while beers like Coors Light, Miller Lite, Budweiser, Corona Extra, Guinness Draught, and Heineken contained even less.

One of the main concerns surrounding glyphosate in Cheerios and Quaker Oats products is the fact that these items are often consumed by young children. The US PIRG report shows even lower levels of glyphosate in beverages consumed by adults.

While the report's authors said their findings were "not necessarily dangerous," further research could uncover new safety concerns. For now, the authors wrote, consumers should remain aware of the "small risk" in consuming glyphosate in beer and wine.