When Did Pesticides Become Table Conversation? Injecting Common Sense into the Discussion About Glyphosate

by | May 9, 2019 | Blog

You know it’s a “hot topic” when glyphosate comes up as a topic from a “friend of a friend” during a brunch conversation. With the recent media coverage of lawsuits in California and the annual release of the Environmental Working Group’s “Dirty Dozen” list, it’s not surprising that talk about pesticides has moved from headline to consumer fear. After all, the term pesticide is not a soothing word. “Cide” is the Latin term “to kill.” In fact, there are over 17 categories of pesticides ranging from antimicrobials (bleach) to herbicides (glyphosate), insecticides (including mosquito repellant) and common items like mothballs.

The Basic Facts

Let’s consider some basic facts. The battle of humans and pests has been going on since the beginning of time as described by Forbes in an Illinois State Laboratory Bulletin in 1915 as follows: “The struggle between man and insects began long before the dawn of civilization, has continued without cessation to the present time, and will continue, no doubt, as long as the human race endures.”1 We all use some form of pesticides to control bugs, germs or weeds in our yards but we trust our decision because we are in control. Once, the use of pesticides is “out of our hands” especially when it is being applied to what we eat, fear and lack of trust enters into our decision making. Why? Is it due to the distrust of science or the farmers that grow our food?

Pesticides usage has come a long way from the 1950s and 1960s thanks to scientific research and the adoption of advanced pest and weed control management by farmers. As a child, I remember my father and brother removing their “spraying clothes” before coming into the house as the pesticides used then were not as safe as today. As Terence Bradshaw mentions in his blog Pesticides Remain a Critical Tool for Sustainable Agriculture, “The agricultural systems that produce our food are much refined from the 1950s and 1960s when the conflation of modern farming and cheap, effective, and, yes, often dangerous pesticides combined to rapidly increase food supply and security in the U.S. and worldwide. Fixation on chemicals from 60 years ago blinds us to the incremental progress that has transformed the food supply in that time.”

Why Herbicides? Glyphosate?

a soybean fieldWhen it comes to growing row crops like soybeans, ideally farmers would not use any herbicides as this additional step increases the cost of “doing business.” However, weed control is vital to the quality and economic value of the crop. Basically, there are two ways to control weeds: use a herbicide or till the soil. From a sustainability standpoint, no-tillage is one of the best ways to conserve the soil and its health. With the no-till method, a herbicide is used to kill weeds on a field prior to planting and at least once after the soybeans start to grow. With the introduction of glyphosate in the 1970s, farmers finally had a safer chemical to use for no-till and conventionally grown crops. However, to really control weeds more than one spray application during the growing season is required.

When Round Up© ready soybeans were introduced to the agricultural community in 1996, the glyphosate usage expanded because farmers could apply the pesticide without harming the crop and decrease the number of applications per growing season to control weeds. Spray applications typically decreased to one-time post planting and in a more precise way without harming the soybean. Over the past 20 years, glyphosate has remained the world’s most widely sold herbicide, used by both farmers and home gardeners. But with this popularity (somewhat related to it being the treatment for genetically engineered crops) comes continued concerns regarding the safety of our health and the environment around us.

The Safety Factor

Glyphosate, like other pesticides, is highly regulated. In 1972, the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) was passed, giving the U.S. Environmental Protection Agency (EPA) control over the sales and licensing of all pesticides. With this action, several popular pesticides at the time were banned in the United States. Science-based limits on pesticide uses and calls for periodic reviews of pesticides in use are included in the regulations. Additionally, laws were passed in the late 1990s concerning worker protection standards and food quality protection. In addition to these regulations, glyphosate is one of the world’s most studied and analyzed chemicals. Global health agencies including the EPA, European Food Safety Authority, Food and Agriculture Organization (FAO), the World Health Organization (WHO), European Chemicals Agency, Health Canada and German Federal Institute for Risk Assessment have all concluded that the levels at which farmers and the general population are exposed to glyphosate, exposure does not pose a cancer risk.

The Controversy

So, if it’s safe, why the controversy? In 2015, the International Agency for Research on Cancer (IARC), a semi-autonomous scientist group of the WHO of the United Nations, concluded that glyphosate is “probably carcinogenic,” using a hazard evaluation rather than a risk assessment commonly used by other agencies. IARC stated there was no risk from the miniscule level of residues found in our food, but that long term exposure to applicators handling the herbicide could increase the risk of non-Hodgkin’s lymphoma.

Here lies the problem. There is a significant difference between “hazard” and “risk” when evaluating the role of toxicology in assessing risk of harm. A hazard is anything that can cause harm, whereas risk is the potential for a hazard to cause harm. Sunshine, alcoholic beverages, red meat and mobile phones have all been classified as hazards by IARC, but exposure (or dose) is what creates the potential harm. Despite the controversial evaluation, this isolated study has been the basis for a number of legal allegations.

The Bottom Line

So, is glyphosate “toxic’ to human health? The simple answer is “No.” Glyphosate, like other approved pesticides, is evaluated by toxicologists using standard scientific measures to determine upper safety limits and tolerance levels, which are hundreds of times lower than the level determined not to cause adverse or harmful issues. Before EPA can register a pesticide for crop protection, it must grant a “tolerance” or the maximum amount of a pesticide that can be on a raw product (when used with good agricultural practices) and still be considered safe.2 Once again, just this week, the EPA confirmed the safety of glyphosate within approved levels and appropriate use of the product.

Farmers are consumers, and like us, are mindful of the risks if pesticides are not used as directed. Good agricultural practices are continuously updated to minimize environmental and human health risks. We, too, need to follow the same level of care when using any type of pesticides whether in our gardens, golf courses or homes. Pesticides (natural or synthetic) are safe when used as directed and at recommended levels. And for added reassurance when it comes to eating fresh fruit and vegetables, always wash your fruit and vegetables (conventional or organic) with water to remove not only a potential pesticide residue but dirt and organic matter. This extra measure of confidence of eating safe food lies within our own hands.

Additional Resources

For more reading on this topic, I recommend the following resources:


1, 2. Perspective on Pesticide Residues in Fruits and Vegetables: Robert Krieger, Personal Chemical Exposure Program Department of Entomology, UC Riverside, Riverside, CA.