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Roundup Toxicity Might Be More Deadly Than Realized

Roudup bottle

The bad news for the pesticide Roundup just continues to get worse.

In March 2015, the International Agency for Research on Cancer (IARC), an agency of the World Health Organization (WHO), released the results of a year-long investigation into the link between glyphosate, the active ingredient in Roundup and cancer. They concluded that glyphosate was “probably carcinogenic to humans.” The maker of Roundup, Monsanto, promptly asked WHO to retract the IARC’s report—WHO refused— and countries in Europe took steps to ban or restrict the use of the pesticide. In January 2016, the company sued the state of California to keep glyphosate off California’s list of carcinogenic chemicals.

But as Monsanto struggles to protect a product that reportedly earned $4.8 billion dollars for the company in 2015, scientists are warning that due to the way Roundup weed killer and many other pesticides are tested, the real amount of Roundup toxicity remains hidden.

Products intended to kill or suppress weed growth, known as herbicides, fall within the Environmental Protection Agency (EPA) definition of pesticide. Roundup weed killer is often referred to as either a pesticide or an herbicide.

Roundup Toxicity – Active and Inert Ingredients

At the center of the controversy over Roundup toxicity is a distinction between two types of pesticide ingredients: active ingredients and “inert” ingredients.

According to the EPA, an active ingredient is a chemical that acts to kill or control a pest or a plant. Inert ingredients (also called adjuvants) are additives that help the active ingredient do its job by:

  • Helping the active ingredient penetrate the leaf surface
  • Improving application by preventing caking and foaming
  • Extending the pesticide’s shelf life
  • Delaying the decay of the pesticide in the environment

Though their name suggests they have no effect on humans or the environment, there is no question that inert ingredients can make pesticides vastly more toxic to humans and animals than the active ingredient alone. And many inert ingredients are themselves toxic. In a 2014 study, French scientists reported that some inert ingredients in pesticides containing glyphosate were 10,000 times more toxic than glyphosate alone. The EPA itself admits that the term “inert” does not imply that a chemical is non-toxic.

It follows that to truly test Roundup toxicity, it would be necessary to test not just the formulation’s active ingredient, but the entire formulation—the combination of all the active and inert ingredients. But this is not done.

“The definition of adjuvants as ‘inerts” is thus nonsense; even if the US Environmental Protection Agency has recently changed the appellation for “other ingredients,” pesticide adjuvants should be considered as toxic “active” compounds.”

Researchers at the University of Caen Institute of Biology in France. Their study, “Major Pesticides Are More Toxic to Human Cells Than Their Declared Active Principles,” was published in Biomedical Research International on February 26, 2014.

In 2006, two experts, Caroline Cox, of the Center for Environmental Health in Oakland, CA and Michael Surgan, of the Office of the Attorney General of New York State, Environmental Protection Bureau, explained the problem of finding the true degree of Roundup toxicity, in a paper published in the journal Environmental Health Perspectives. Most of the tests required to register a pesticide in the United States, they said, do not require that the full formulation of a pesticide be tested. None of the medium term and long term tests—those needed to determine whether a pesticide causes cancer or genetic harm—require that the entire formulation be tested. Those tests are conducted on the active ingredient alone.

Adding to the problem of determining Roundup toxicity is the fact that manufacturers are not required to list the inert ingredients on the label and since the formulations are considered trade secrets, they are not required to disclose the ingredients to the public. This makes it difficult or impossible to determine how many toxins a pesticide contains.

Roundup Toxicity Increased by Inert Ingredients

Cox and Surgan reviewed the results of numerous studies that compared the toxicity of a variety of pesticide formulations with the toxic effects of the pesticides’ active ingredients alone. In each case, the formulation was found to be much more toxic than the active ingredient.

The authors cite several studies involving Roundup toxicity.

In one, the genotoxic effects (damage to the genetic information [i.e., DNA in a cell]) of Roundup were found to be much higher than glyphosate alone. This is particularly significant since DNA damage can cause mutations and cancer. (The lead author of the WHO glyphosate study told the Reuters news agency there was “strong supporting evidence showing DNA mutations and damaged chromosomes.”)

In another study, Roundup was found to be much more lethal to the human placenta cell than glyphosate alone. Roundup was also found to inhibit the activity of an enzyme (aromatase) that plays a key role in the body’s endocrine system. Glyphosate alone did not inhibit the enzyme.

The Toxicity of Inert Ingredients

Several French scientists have been investigating  Roundup toxicity for the past decade. Their research confirms the conclusions that Cox and Surgan reached in 2006 and expands upon them.

Four investigators at the University of Caen recently tested the toxicity of nine pesticides and found that “8 formulations out of 9 were up to one thousand times more toxic than their active principles. But the increased toxicity of the formulation is not only the result of inert ingredients making the active ingredient more toxic. Inert ingredients may actually be more toxic than the active principle itself. One of the Caen researchers, Gilles-Eric Seralini, exposed human umbilical, embryonic and placental cells to Roundup and one of its adjuvants in 2009 and discovered that the adjuvant polyethoxilated tallowamine, or POEA, was more deadly to the cells than glyphosate. “POEA,” he wrote, “could be considered as the active ingredient on human cell death and more damaging than G [glyphosate].”

How many of the so-called “inert” ingredients in Roundup and other pesticides are actually toxic? Since inert ingredients are generally not identified, it is difficult to do the tests required to answer this question. Cox and Surgan found only six studies that performed three-way comparisons between a complete pesticide formulation and both the active ingredient and an inert ingredient contained in the formulation. In three of the studies, it was found that the increased toxicity of the formulation was not the result of the inert ingredient enhancing the toxic effects of the active ingredient, but was the direct result of the toxicity of the inert ingredient itself.

Not surprisingly, all of these scientists call for a change in the way pesticides are tested. Unless that happens we may never know how deadly Roundup toxicity really is.

Taking Action

If you or someone you know was exposed to Roundup toxicity and subsequently diagnosed with cancer, please contact the Roundup cancer attorneys at Baum Hedlund Aristei & Goldman for a free consultation.



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