When the World Health Organization (WHO) declared glyphosate a probable carcinogen in 2015, many people wondered why the government wouldn't make it mandatory to inform the public when a food contains genetically modified ingredients. Many GMO foods contain glyphosate, the active ingredient in Monsanto's Roundup weed killer, which is engineered into the seeds they're grown from.

The following year, WHO reported that "glyphosate is unlikely to be genotoxic at anticipated dietary exposures." In essence, the organization clarified the claim by saying that the chemical could cause cancer in humans but that it doesn't think humans ingest enough of it to be harmful.

How much glyphosate is harmful to humans?

A honey bee sits on a flower Bees collect glyphosate from plants that have been sprayed with weed killer, and it ends up in their honey. (Photo: Ivar Leidus/Wikimedia Commons)

The WHO's clarification leads me with this question: How much glyphosate is too much? Does anyone know?

What we do know is that increasingly, traces of glyphosate are found in foods, including some that should never come in contact with the chemical.

When the Food and Drug Administration tested honey for glyphosate, the agency found some of the samples showed "double the limit allowed in the European Union." The U.S has no limit for honey since glyphosate is never directly applied to bee hives.

The glyphosate is making its way into honey via the bees that collect it from sprayed plants, which can't be controlled. An FDA chemist told Huffington Post that the residue in honey is "technically a violation," but bee farmers are not breaking laws because they aren't the ones using the weed killer.

When The Alliance for Natural Health-USA tested popular breakfast foods for evidence of glyphosate, the tests found that even organic eggs — eggs from chickens that are not permitted to be given GMO feed — had traces of glyphosate in them.

The concern is that somehow glyphosate is ending up in our bodies, sticking around and doing some harm. But, again, how much needs to stick around in an adult's body to do harm? How about a child's body? What about a pregnant woman's body?

What good are tests if we don't know how to interpret the results?

ice cream Is any level of glyphosate in ice cream acceptable? (Photo: Job Narinnate/Shutterstock)

Recently, Ben & Jerry's announced it would cut "glyphosate-tainted ingredients from its production chain and introduce an 'organic dairy' line next year." An outside source found that 13 out 14 tubs of ice cream showed traces of the chemical, traces far below the acceptable limits in the European Union — meaning there's not a lot of the chemical to be found. A child would have to eat 114 ml (about half a cup) daily of the glyphosate-tainted Ben & Jerry's ice cream over many years before any harm would be done, according to European food safety authority guidelines. Still, by 2020, the company is committed to ridding the ice cream of all traces of glyphosate.

When the organization Moms Across America independently tested five major brands of orange juice, the tests found results ranging from "4.33 parts per billion (ppb) to an alarming 26.05 ppb." The information was sent to journalists with one piece of information missing: what the Environmental Protection Agency considers the acceptable amount, or tolerance, of glyphosate in orange juice. If the EPA has set a tolerance, a search on the Code of Federal Regulations did not uncover it. There is some information about citrus, but not orange juice specifically. An email to Moms Across America for the information was not answered.

Without that basic information, it's difficult to start forming an opinion. There's no way to know if those numbers are high or low.

What should consumers do?

Lots of 'farm fresh' box services have been popping up, promising organic fruits and veggies delivered to your door. Growing your own food is one way to lessen your exposure to glyphosate and other pesticides. (Photo: Dasha Petrenko/Shutterstock)

In addition to being in GMO seeds, Roundup is used on more than 750 agricultural, household and forestry products, and the weed killer is not the only product that contains glyphosate. It's the most-used agricultural product ever in the U.S. About 300 million pounds of glyphosate are applied on plants in the U.S. each year, according to numbers from 2006.

The U.S. Department of Agriculture recognizes glyphosate as a safe chemical. It's been used since 1974, but the FDA didn't decide to test for glyphosate residue in food until 2016, Yet, it's been linked to cancer. It may kill helpful gut bacteria, and it's also been linked to diabetes, autism, obesity and heart disease. The state of California sees enough evidence of its harmfulness to declare it a carcinogen and has given companies a year to label products containing glyphosate.

Five countries — Belgium, Argentina, Malta, Sri Lanka and the Netherlands — have banned the use of glyphosate. And just this week, the European Union delayed a decision on extending the license for the popular weed killer. That license expires at the end of this year.

One group has launched a tool called The Detox Project that allows consumers to test their urine levels for residue. You can learn more about that project in the video below:

Doesn't all this information leave you with more questions than answers? It does me.

If the concerns about glyphosate make you want to limit your exposure to it, choose organics whenever possible. Products with glyphosate are not allowed to be used on organics. Buy from farmers who you know don't use the chemical. Grow your own food if you can. It won't be possible to completely avoid glyphosate, but those actions should lessen your exposure.

Be vocal with the U.S. government about wanting transparent, accurate information about glyphosate testing and glyphosate safety. Yes, the FDA began testing for glyphosate residue last year after finding levels of glyphosate in honey and other foods. However, it also quietly suspended the testing for a while but resumed again in June, according to Huffington Post. It's only through the Freedom of Information Act that any details about testing — or not testing — have come out.

Robin Shreeves ( @rshreeves ) focuses on food from a family perspective from her home base in New Jersey.