Pesticides In Dog Foods

pesticides in dog foods

If you feed kibble, your dog is almost certainly eating chemical herbicides or pesticides for dinner. That’s because kibbles often contain genetically modified (GM) ingredients, like corn, soy, canola or alfalfa, grown with herbicides and pesticides. Or OWL foods (oats, wheat, legumes) that are harvested using glyphosate as a dessicant. And that’s why there are pesticides in dog food.

GMOs are a controversial topic. Their safety hasn’t been proven … but it’s hard to find research that confirms any negative effects of GMOs. Most of the studies are funded by the companies that create them. 

But, regardless of the safety of the individual genetic modifications, there’s one thing that’s undeniable about GMOs …

GMOs Increase Pesticide and Herbicide Use

GMOs have resulted in enormous increases in the amount of chemicals sprayed on food crops every year. Soy and corn are almost all GMO (except for organic varieties). The problem is that the weeds Roundup® (glyphosate) was designed to kill (and GMO plants were engineered to resist) … have developed resistance. So there’s heavier and more frequent application of glyphosate. 

Foods with high pesticide or herbicide risk include …

  • Almonds
  • Apples
  • Barley
  • Beans and other legumes
  • Beets
  • Canola
  • Collard
  • Coirn
  • Kale
  • Millet
  • Oats
  • Peppers
  • Potatoes
  • Sorghum
  • Soy
  • Spinach
  • Strawberries
  • Sunflower
  • Tomatoes
  • Wheat

Glyphosate is the best known of these chemicals, but commonly used herbicides include other chemicals. These are often “stacked” onto a basic formula, such as glyphosate AND Bt toxin (of which there are at least 6 forms). There are at least 750 formulations of glyphosate in use today. Research suggests that the “inert” or “other” ingredients,” including adjuvants, used with glyphosate may be even more toxic than glyphosate itself. Some formulations were found to be up to 1,000 times more toxic than others.

So let’s take a look at these chemicals. 

Glyphosate (Roundup®)

The most “famous” GMOs are those engineered to tolerate spraying with glyphosate products like Roundup®.. Corn and soy are the primary GMO crops. Glyphosate is not only sprayed on the surface but taken up into the plant … so it’s impossible for consumers to wash the glyphosate off. Because multiple heavy applications of glyphosate are needed to overcome weed resistance, all GMO foods are relatively high in glyphosate.

Glyphosate in Non-GMO Crops

Many non-GMO crops, particularly grains and legumes, are sprayed with glyphosate just before harvest, as a “desiccant.” Since these crops are not engineered to resist glyphosate, the glyphosate kills the plants and dries them out. So the crop can be harvested earlier and at a more uniform level of moisture, which benefits the growers. 

Independent testing has found high levels of glyphosate in OWL crops. OWL stands for oats, wheat, and legumes (chickpeas, lentils, black beans, pinto beans, etc.). But this practice also extends to potatoes, apples, avocados, blueberries, sugar beets, nuts (especially almonds), sorghum, rice and barley). 

Glyphosate has been detected in many pet foods. It’s found at much higher levels in all kibbles than in raw pet foods. Tests by HRI Labs showed kibble was as high as 660 ppb (parts per billion), compared to only 5 ppb for raw foods. Canned and freeze-dried foods tested at around 17 ppb.

Glyphosate is largely excreted in the urine. But one study found glyphosate in dog urine at more than 30 times that of humans.

Here are some of the possible problems glyphosate can cause … 

Health Risks Of Glyphosate

  • Cancer (the WHO has designated glyphosate “a probable carcinogen”
  • Liver damage
  • Kidney damage
  • Harms gut bacteria, causing leaky gut and immune problems
  • Endocrine disruption
  • Digestive problems
  • Allergies
  • Cognitive and behavior issues

Bt Toxin

With glyphosate hogging the spotlight. what most people don’t realize is that the genetically engineered Bt toxin, also engineered into the genomes of corn and soy, is even more harmful. Bt stands for Bacillus thuringiensis. It’s in the same family as B anthracis that causes anthrax.

It’s toxic to insects and used as an agricultural pesticide. Gardeners know it as a “safe” pesticide that’s even allowed in organic farming. But the altered Bt toxin is very different. 

Early assessments were based on unreliable models, and don’t reflect the behavior of the toxin within plants in real life. The way it works is by damaging the insect’s cell membranes, causing the stomach to burst. So you can imagine the damage it can do to your dog’s digestive system … or yours.

Engineered plants can express up to six different Bt toxins, produce unique allergens, persist longer in the gut and the environment, alter the microbiome, and act as endocrine disruptors. 

The GMO Bt gene comes with its own adjuvants (promoters) that keep the Bt toxin reproducing inside every single one of the plants’ cells. When animals eat the plant, Bt can bind to the intestinal wall and transfer the genes to the resident bacteria in the gut. 

In other words, animals that eat Bt corn build little Bt factories in their intestines. These keep producing more and more Bt. And it’s not eliminated from the body … research shows it remains for weeks after exposure. The adjuvants also stimulate the immune system to make antibodies – the first step toward food allergies, and even cancer. Here are some other known problems caused by Bt toxin … 

Health Risks Of Bt Toxin

  • Leaky gut and other digestive issues
  • Food poisoning
  • Endocrine disruption
  • Lung damage
  • Eye irritation, blindness

Inert Ingredients May Be Harmful Too

Agrochemicals are not used by themselves. They’re formulated with other chemicals, called “inert ingredients.” However, they may not be so inert, since that is a regulatory term and has nothing to do with real-world toxicity. 

Adjuvants included in some glyphosate formulas have been cited as far more toxic than the “active ingredient” glyphosate. To cloud the issue further, many tests done on “glyphosate” were actually done on multi-ingredient formulas …but failed to mention the other chemicals. We really don’t understand the effects of long-term, low-level consumption of any of these compounds.

While even organic products may not be entirely free of pesticides and herbicides that get spread by wind and rain … at least they haven’t suffered direct application. So they’re a better choice than conventional crops.

RELATEDRead more about GM ingredients in dog food …

All this means that, unless you feed kibble with 100% organic ingredients, your dog’s swallowing these toxins. Safer choices include freeze dried foods, or some canned foods … and best of all is a raw diet, even if it’s made with factory-farmed meats. And if you feed a raw or cooked homemade diet pay attention to ingredients and choose organic if the produce is on the Environmental Working Group’s Dirty Dozen list of foods with the highest pesticide levels. 

How safe is your dog’s food? Visit to find out …


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