Dangers of Pesticides
Article by Stefan Burns - Updated November 2021. Join the Wild Free Organic email newsletter!
The human body, the foods we eat, the air we breathe, and the planet we live on are made up of millions of chemicals. Water, with the chemical formula of H2O, is the main chemical that our bodies are comprised of, being necessary for thousands of essential chemical reactions, and without water you die. Still, water intoxication is possible though. With any chemical, the dose determines the poison, as does the length of exposure to it. For some chemicals like water, multiple gallons of water consumed very quickly is required to reach a median lethal dose (LD50), while some chemicals can be fatal at even less than a gram. Other chemicals like pesticides might not kill you directly, but will affect your health in more insidious ways, and 90% of Americans have been found to have pesticides and byproducts in their bodies (1).
Pesticide usage in agriculture is widespread, being used on 90% of agricultural lands in the US. Herbicides are a type of pesticide.
Exposure to chemicals overtime is very important to consider for this reason. A small dose of a chemical like a residual herbicide might acutely cause no apparent harm, but over time and with consistent exposure to many different herbicides, chronic health conditions can arise which severely impact overall health and wellness and ultimately lead to fatal outcomes. Reducing exposure to chemicals that harm human health over long periods of time as much as possible is a very important aspect of a healthy lifestyle. Herbicides are so widespread in their use that limiting exposure to them can be difficult and requires lifestyle modifications. Therefore consciously voting with your dollar and purchasing foods and products that aren’t contaminated with pesticides is important. Once food and product changes have been made, monitoring your chemical exposure doesn’t require any conscious thought more than an periodic check-in.
One class of chemicals that is out of sight and out of mind for most are pesticides. Pesticides are chemicals used to control pests and weeds, and include all of the following: herbicide, insecticides, fungicides, bactericides, rodenticides, and insect/animal repellents. Herbicides like glyphosate and chlorpropham are the most commonly used pesticide in the United States, and they trace their origins back to the military industrial complex of World War 1 and 2.
Increased Usage of Herbicides
Herbicides were first synthesized in the early 1940’s, and originally researched for use during WW2 as a warfare agent. The primary intention of herbicidal warfare was to destroy the plant-based ecosystem of an area. Fiction turned to reality with Vietnam when herbicidal warfare was carried out to thin the thick jungles of Vietnam, and thousands perhaps millions have suffered the effects of this massive herbicidal warfare campaign. Herbicidal warfare has been forbidden since 1978, yet the chemical and agricultural industry increasingly wages herbicidal warfare on the civilian populations of the world through the broad usage of herbicides on agricultural crops. Millions of acres are now heavily contaminated with herbicides that take up to decades to break down.
90% of agricultural cropland is treated with chemicals each year, and an estimated 300 million acres are treated with pesticides each year (also about 90 percent). In the U.S., cropland receives on average about 3 pounds of active ingredient per acre, equating to nearly a billion pounds of pesticides used in total per year. Divide that by the U.S. population and that equals pounds of pesticide active ingredient used for every woman, man, and child (see image 2). Pesticides are commonly used on urban lands too, and at a higher rate of usage (2).
The data above compiled by the Center for Integrated Pest Management only goes up to the year 2000. Since 2000, world pesticide usage has gone up, with some countries decreasing their pesticide usage while others have increased their pesticide usage (3). Pesticide usage in the United States is at the highest its ever been from 2010 onwards.
Mechanisms of Action as Weed Killers
There are many plants labeled as weeds and sprayed with herbicides that are in fact helpful native plants that create beneficial habitat and food for many different insects, birds, and animals. The term weed is incorrectly used very broadly and to the detriment of holistic ecological understanding.
There are many different mechanisms of action that herbicides take to kill plant life. There is significant overlap and interdependence in biology, and it is through the same or similar mechanisms as below that herbicides cause health issues in humans and negatively affect the human microbiome.
ALS Inhibitors: Acetolactate synthase is the first step in the synthesis of the branched-chain amino acids leucine, valine, and isoleucine. ALS inhibiting herbicides starve plants of these amino acids, inhibiting DNA synthesis and causing death. The ALS pathway does not exist in animals, but many organisms in animal microbiomes utilize the ALS pathway.
EPSPS Inhibitors: Enolpyruvylshikimate 3-phosphate synthase enzyme (EPSPS) is used in the synthesis of the amino acids tryptophan, phenylalanine and tyrosine via the shikimate pathway. Glyphosate (Roundup) is a systemic EPSPS inhibitor.
Photosystem I and II Inhibitors: Photosystem inhibitors affect electron flow, ultimately causing oxidation reactions in different cellular structures which can kill a plant.
Synthetic Auxins: Synthetic auxins mimic plant hormones in various ways. Growth of plants can be controlled via their hormone systems, with synthetic auxins exerting their effects by docking on the membrane of cells.
HPPD Inhibitors: 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors affect the breakdown of the amino acid tyrosine, the breakdown products of which are used to make carotenoids. Carotenoids protect chlorophyll from damage by sunlight, and without protection plants that have inhibited carotenoid production turn white as chlorophyll die and then the plant dies.
The general way herbicides function is through affecting biochemical processes involving amino acids, oxidative systems, and hormonal systems of plants. These are very important foundational biologic systems that when disrupted kill plants and other organisms like bacteria. To introduce into your own biochemistry any of these chemicals can affect your health and the health of your microbiome over long periods of time.
Glyphosate (aka Roundup)
Glyphosate is used as a herbicide because it is very effective at killing plants. Glyphosate is an herbicide which disrupts the shikimate pathway, a metabolic pathway used by bacteria, archaea, fungi, algae, some protozoans, and plants. The shikimate pathway consists of seven-steps, and is used by these organisms, but not animals, for the synthesis of folates and certain amino acids. Animals instead must obtain these essential amino acids through their diet, and it is for this reason that agrochemical companies say that glyphosate exposure is okay for humans.
Glycine-Glyphosate Substitution
The interactions of glyphosate in the human body are more complex than claimed by the agrochemical industry. Glyphosate is composed of the amino acid glycine, an important amino acid that is commonly deficient in humans (4), and a phosphonomethyl group that replaces one of the hydrogen atoms. Glycine is a non-essential amino acid, meaning the body can produce it, but its synthesis requires other nutrients, and depending on the biochemical situation, the body might decide to not synthesize glycine. Glycine then could be pulled from connective tissues, where it is the dominant amino acid, and then utilized throughout the body (but to the detriment of joint health), and/or glyphosate could be substituted in. This swap can happen because glyphosate is similar to glycine, and the process is known as glycine-glyphosate substitution (5). Most of the health effects of glycine-glyphosate substitution are still unresearched.
A common glyphosate side effect is poor gut health. Since glyphosate targets the shikimate pathway, it acts as an antibacterial to the microbiome, and this can lead to problems like food allergies and intolerances, IBS, IBD, leaky gut, and malabsorption of food. Glycine can be synthesized internally, but it is easier to acquire via diet by eating the connective tissues of animals or by eating glycine rich foods like pulses (lentils, beans, chickpeas, etc). Glyphosate through its mechanisms disrupts the health of the digestive system, weakening digestive tight junctions, in the process reducing the ability to absorb glycine from dietary sources. Through this insidious effect the body begins to start glycine-glyphosate substitution, and the process gradually worsens while other bodily system that have incorporated glyphosate into their protein structures instead of glycine become newly stressed.
Glycine-glyphosate substitution is bad news because glycine is a very important amino acid throughout the body. Glycine has been shown to improve sleep (6, 7), is an integral component of connective tissues, helps heal injuries (8), and has anti-inflammatory effects (9). Some common glyphosate side effects include poor sleep, digestive problems, brain fog, skin issues, joint problems, thyroid issues, and fatigue.
Glyphosate can be a contributing factor to gluten intolerance. I personally have had gluten intolerance, and it took me many years to heal my gut to perfect health. Take it from me, determining whether gluten or glyphosate is the problem is difficult, so when making dietary modifications it is best to remove both.
The foods which are the most contaminated with glyphosate are GMO products. GMO crops like wheat, soybeans, and corn have been genetically modified to better resist the effects of herbicides like glyphosate. Now with better herbicide resistant GMO crops, the agricultural industry can spray glyphosate and other herbicides in much greater quantities, contaminating the food supply in even greater amounts. When tested non-gmo crops were found to have glyphosate residues at 0.07 mg/kg to 0.09 mg/kg. For a GMO crop, the range was found to be between 3.3 and 5.7 mg/kg (10). This is approximately a 100x difference. Look for the Non-GMO Project verified label on foods, and for your health and the health of the Earth don’t buy GMO foods. Buying only GMO can be difficult, especially if you live in a food dessert.
Finding glyphosate free flour or glyphosate free oats, two commonly contaminated foods, is difficult, though it is becoming easier as more organic and non-gmo products are brought to market. Non-GMO and gluten-free bread products are readily available now in most grocery stores, and these will be much less contaminated, or even free, of glyphosate residues. Finding oatmeal, buckwheat, cereals, and beers without glyphosate is possible when shopping for Non-GMO gluten-free products, of which there are many…and they are very tasty! For the best chance of buying foods without glyphosate, purchase organic, non-gmo, gluten-free products.
If you are unable to buy foods free of glyphosate contamination, focus your diet on whole unprocessed foods and plenty of fruits and vegetables. Glyphosate residues can be washed off on some fruits and vegetables using a dilated mixture of baking soda and water, which is an effective surface pesticide rinse (11). Growing your own fruits and vegetables is the best way to ensure you’re no exposing yourself to the dangerous herbicide glyphosate among many other pesticides.
Chlorpropham and Propham
Propham and chlorpropham are synthetic herbicides and plant growth inhibitors most commonly known for their ability to stop potatoes from sprouting. Chlorpropham applications are also used on spinach, blueberries, garlic, tomatoes, carrots, onions, soybeans, and much more. Chlorpropham’s mode of action is by altering microtubule structure and function in plants resulting in the inhibition of cell division (12). Once potatoes are harvested and ready for storage, chlorpropham dust or propham dust is applied to potatoes via a method known as hot fogging. The potato growing industry will store potatoes for up to 9 months, and during this time chlorpropham will be hot-fogged many times to keep sprout suppression under bay.
During storage, mean concentrations of chlorpropham in tubers decreases with time, with 25% gone in a month and 40% gone in two months. Chlorpropham primarily resides in the peel of potatoes, washing potatoes will remove approximately 40% of the chlorpropham while peeling the potatoes will remove 95% of the herbicide. If the potatoes are boiled or fried, chlorpropham residues can be found in the water and oil used (13).
A naturally grown potato will sprout after some time, like shown here, as it’s still alive and able to perform cellular division.
Through chlorpropham’s growth inhibition characteristics, it has been shown that mice, rats, and beagle dogs feed chlorpropham for short periods of time become anemic, undergo weight fluctuations, and have altered thyroid function, with the hematopoietic system being the main toxicological target found with chlorpropham exposure (14). The hematopoietic system is the bodily system involved in the creation of the cells of blood, with the blood cell genesis sites being bone marrow and the lymph nodes.
Chlorpropham has low mammalian toxicity, but it can bioaccumulate and begin to affect major systems of the body.
The EPA assessed the dietary risk posed by chlorpropham (15), and based on a reference dose not believed to cause adverse effects if consumed daily over 70 years, they found chlorpropham to be safe. 42% of the U.S. population is exposed to that much chlorpropham daily, and while the short chlorpropham studies lasting no greater than 24 months showed very troubling health concerns for the animals involved, 70 years of chronic exposure has been signed off by the EPA as OKAY. The fact that chlorpropham is used in great enough concentrations to cause a physiological effect in potatoes, inhibiting their natural life cycle and stopping sprouting, is reason to believe that chlorpropham is used at great enough concentrations to cause long term health effects in humans with regular ingestion.
Through these mechanisms and how often exposure occurs, chlorpropham and propham can be classified as endocrine disruptors. Just as these herbicides affect cellular growth and reproduction (mitosis), low doses over time can threaten thyroid, lymph node, and hematopoietic health. Thyroid conditions affect ~20% of the U.S. population (16), and this percentage is increasing. There are a lot of diseases of the hematopoietic system (17), and some of them could be caused or affected by chronic herbicide exposure.
How to Avoid Herbicides
There are four steps that can be taken to limit your exposure to herbicides. Each step will reduce your exposure, and if all three steps are followed then your herbicide exposure risk will be close to zero.
Wash Fruits and Vegetables: Washing and/or soaking fruits and vegetables with a 1% baking soda and water mixture can remove pesticide residues. Some pesticides that only coat the outside of produce will break down or bind to the baking soda and be rinsed away, whereas this method is less effective with pesticides that penetrate deep into fruits and vegetables. To create the pesticide rinse, mix 3 tablespoons of baking soda into a gallon of water.
Buy Non-GMO Food: With the advent of gene editing technology, genetically modified organisms have been created and are now abundantly in the food supply. Through selective breeding has influenced plant and animal genetics for thousands of years, direct genetic modification can insert genetic code from a other organisms such as a worm into the DNA of a plant. The long term health effects of consuming genetically modified organisms is unknown, and the larger concern comes from how GMO crops are managed compared to non-GMO crops.
Buy Organic Products: The organic certification is regulated by the United States Department of Agriculture (18), and while it is a step in the right direction, it has many loopholes. It only takes 36 months to transition from regular production to being organic certified by the USDA. Since hazardous chemicals can contaminate soil and water for years, there is still risk of herbicide contamination with organic products. Additionally, animal manures from conventional feedlot and confinement systems are allowed in organic production, and so is manure from animals that have been fed genetically engineered feeds (aka highly herbicide contaminated feeds).
With that said, organic farms use techniques such as composting, soil building, chemical free pest management, crop rotation, and many other holistic agricultural techniques. The variability within the organic standard is wide ranging. There can be an organic farm which uses no chemicals or contaminated materials, and there are organic farms which skirt the edge of the regulations. It’s the same product same quality fallacy. As an informed purchaser it’s your responsibility to research the companies you purchase food and products from, and to only support those who practice ecologically safe and sustainable farming practices.Shop at Local Farmers Markets: Sourcing your food from local farmers markets, or growing it yourself, is the final and best way you can distance yourself from herbicides and other chemicals. If you grow your own food, you can complete control from start to finish, and there is no reason to use chemicals when environmentally friendly methods of soil building, weed management, and pest management exist and are easy to apply at a small scale.
If you don’t have space for a garden, or during the seasons where growing without a greenhouse is difficult, shopping at a local farmers market is an excellent solution to the problem of where to acquire high quality contamination free fruits, vegetables, and animal products. When shopping at a farmers market, you can speak with the grower and find out how they grow their food. Additionally, produce at farmers markets is typically less expensive than found in a grocery store, and every dollar spent goes directly to a member of the local community.
Engage with the community, save money, and buy interesting and unique foods at your local farmers market.
There are also micronutrients which can internally help protect you from pesticides. Boron protects against the oxidative stress from pesticides (19), as do powerful antioxidants like anthocyanins found in elderberries.
Your Health is Your Responsibility
Agroindustrial chemical companies will argue that herbicides and other pesticides are not harmful to human or animal health at the limits required by law, and while a lot of research has been done, it has not been conducted across the right time scales or with the right combinations of pesticides. Chemical producers have betrayed the trust of the public many times through faulty science, redacted data, chemical pollution, cover-ups, lobbying, and millions have died from the chemicals produced by these large multinational corporations formed during WW1 and WW2.
Your health is your responsibility, and when there are food alternatives not contaminated by hundreds of pesticides and herbicides which are easily accessible at a local farmers market, the right choice is easy to make. The risk of eating conventional produced grains, meat, and produce is simply too great, and the only short term reward from purchasing food from the agroindustrial complex is a few dollars saved. The long term effects could be chronic health conditions that untreated could lead to death.
Find a farmers market near you, support your local community farmers, and thrive.
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Yamadera, W., Inagawa, K., Chiba, S., Bannai, M., Takahashi, M., & Nakayama, K. (2007). Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes: Effects of glycine on polysomnography. Sleep and Biological Rhythms, 5(2), 126-131.
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