By Matt Worthy, Founder, ScienceBod.com

A major reason why many people opt for organic produce is to avoid exposure to pesticides used in non-organic farming. It turns out, that is a very good reason to choose organic. In Europe, 75% of non-organic fruit and 32% of non-organic vegetables tested positive for pesticides. [1] When testing organic versus non-organic crops for pesticide residues, there is a four-fold drop in contamination with organic produce. In 2015, the European Food Safety Authority found that 13.5% of organic produce and 46.8% of non-organic produce tested positive for pesticide exposure. Disturbingly, 0.7% of organic produce and 2.9% of non-organic produce exceeded the “maximum residue limit” that is considered safe for human consumption. [2] The reason that even organic foods can sometimes carry detectable pesticides is because of cross-contamination from nearby non-organic fields or orchards, or persistent contamination from past non-organic farming.

Think twice before you eat non-organic food.

In the US, pesticide contamination information is more difficult to obtain. The US Department of Agriculture (USDA) administers a voluntary program called the “Pesticide Data Program” (PDP). It does not distinguish between organic and non-organic produce though a 2002 study found that, in the US, “organically grown foods consistently had about one-third as many residues as conventionally grown foods.” [3]  Reassuringly, a one-time 2010-2011 pilot study of organic produce pesticide exposure in the US administered by the USDA shed some light on the state of organic produce in America: it found 96% compliance with organic standards. Out of 110,190 analyses performed in the study, 413 pesticide detections occurred; a rate of 0.4%. [4]

For conventionally grown foods in the US, the situation is not nearly as encouraging. An independent watchdog organization called “The Environmental Working Group” (EWG) analyzed the USDA’s latest data from the PDP and calculated “nearly 70% of samples of conventionally grown produce were contaminated with pesticide residues.” [5] This figure does not include crops contaminated with the ubiquitous “glyphosate”, which is the active ingredient in the “Roundup” weed killer developed originally by the giant Monsanto chemical corporation, and since the expiration of Monsanto’s Roundup patent in 1991, manufactured widely to become the mainstay for weed control in 130 countries. [6], [7]

Unbelievably, the PDP does not screen for glyphosate, which the journal, Applied Soil Ecology, explained in 2018 “is a known endocrine disruptor as well as a probable carcinogen.” [8] In fairness, though, while the World Health Organization’s International Agency for Research on Cancer has also labeled glyphosate a “probable carcinogen”, both European pesticide regulators and the US Environmental Protection Agency disagree with that conclusion. [9]

However, in a landmark case from the summer of 2018, a jury in a San Francisco, California lawsuit in superior court “found Monsanto liable for a school groundskeeper’s lymphoma that he said developed after years of applying the company’s trademarked Roundup weed killer,” and awarded him $289 million, $250 million of which were punitive damages. [10] A judge later reduced the $289 million total award to $78 million due to a requirement that the ratio between punitive and compensatory damages cannot exceed a one to one ratio in California cases. [11] Earlier in 2018, Monsanto was acquired by and folded into German pharmaceutical and pesticide giant Bayer. [12]

The verdict stated in the affirmative that Monsanto “acted with malice or oppression” in their conduct and that the “malice or oppression” was “committed, ratified, or authorized by one or more officers, directors, or managing agents of Monsanto acting on behalf of Monsanto.” [13] Part of that finding of malice stemmed from evidence presented at trial that Monsanto helped to ghostwrite articles in a special 2016 edition of the scientific journal Critical Reviews in Toxicology concluding glyphosate was not carcinogenic. Proof of Monsanto’s interference in the publication process prompted Critical Reviews in Toxicology to investigate and, in September 2018, issue a rare “Statement of Concern” regarding their special glyphosate volume explaining that the authors of five articles in that issue did not adequately disclose the role Monsanto played in their works and could not account for “why the necessary level of transparency was not met on first submission.” [14] The verdict could open the floodgates against glyphosate and Bayer. Currently, in the US alone, 8,700 lawsuits are pending, “alleging that exposure to glyphosate-based herbicides led to various types of cancer.” [15]


In the summer of 2018, Monsanto, now merged into Bayer, was hit with a $278 million jury award for acting with “malice or oppression” that was “committed, ratified, or authorized by one or more officers, directors, or managing agents of Monsanto acting on behalf of Monsanto .” The award was later reduced to $78 million due to a technicality in California law.

Beyond Roundup and glyphosate, a random sampling of data from the PDP’s 2015 report offers some disturbing insights. For example, 30% of grapes were exposed to a fungicide called “quinoxyfen”. 43% of strawberries tested positive for an insecticide named “imidacloprid.” Farm workers exposed to imidacloprid suffered from skin and eye irritation, dizziness, breathlessness, confusion and vomiting. Exposed pets have drooled or vomited after exposure. [16] The insecticide, “flonicamid”, which the US Environmental Protection Agency warns is a possible carcinogen, was detected in 26% of spinach sampled. [17], [18]

Each year, the EWG produces lists for consumers highlighting the “cleanest” and “dirtiest” produce items. These lists are called “The Clean Fifteen”, and “The Dirty Dozen.” The Clean Fifteen are the fifteen fruits or vegetables least likely to contain pesticide residues according to USDA data. The Dirty Dozen, on the other hand, are virtually guaranteed to bear pesticides.

The Clean Fifteen fruits and vegetables for 2018 were avocados, sweet corn, pineapples, cabbages, onions, frozen sweet peas, papayas, asparagus, mangoes, eggplants, honeydews, kiwis, cantaloupes, cauliflower and broccoli. Less than one percent of avocados and sweet corn manifested any signs of pesticides; a rate better than many organically produced products.

The Dirty Dozen included, in order of contamination: strawberries, spinach, nectarines, apples, grapes, peaches, cherries, pears, tomatoes, celery, potatoes and sweet bell peppers. More than 98% of strawberries, cherries, spinach, nectarines, apples, and peaches tested positive for pesticides. Some of The Dirty Dozen were loaded down with more than 20 different kinds of pesticides. [19] Strawberries demonstrated exposure to as many as 36 different chemicals. [20]

Strawberries in the US test positive for as many as 36 separate chemicals.

Cynics criticize the organic food movement for a lack of evidence tying the consumption of organic food products directly to longer lives and increased healthspans. However, there are mountains of evidence correlating the benefits of diets rich in food-based antioxidants, polyphenols, vitamins, and minerals to improved aging. There also exists no shortage of proof that pesticides and other toxins can shorten our lives by causing disease. For example, 46-year old DeWayne Johnson, the groundskeeper plaintiff in the glyphosate case against Monsanto discussed above, has less than two years to live as a result of the Non-Hodgkin Lymphoma he developed after exposure to Roundup weedkiller. [21]

Several commonly used pesticides, for instance, have been implicated in Parkinson’s Disorder for their ability to cause oxidative damage and interfere with mitochondrial function. Two of those pesticides are “pyridaben”, which pears in the US test positive for, and “fenpyroximate”, which turns up in strawberries, tomatoes, grapes, and pears. [22], [23] “Spinosad”, a commonly used insecticide, which cherries and spinach often test positive for, was shown by Chinese scientists in 2016 to cause DNA damage and cell death in human kidney and liver cells. [24] Dr. Doug Wallace, the director of the Center for Mitochondrial and Epigenomic Medicine at Children’s Hospital of Philadelphia and one of only 25 foreign members of the Italian Academy of Sciences (other foreign members have included Albert Einstein, Benjamin Franklin, and Louis Pasteur), explains that, with the rise of the use of agricultural chemicals as the population expands, “we haven’t really thought deeply enough about what low-level chronic toxicity of some of these chemicals might be.” [25]

Governments do not require testing of different combinations of pesticides or herbicides or fungicides. It is entirely feasible that in one meal, we could be exposed to dozens of different hazardous chemicals, especially if the meal included one or more items from “The Dirty Dozen.” Remember, one strawberry could contain up to 36 separate agricultural chemicals. No one knows what those combined dangers are. They have not been tested for.

What is known is that many pesticides are more toxic than the companies who produce them or the governments who test them are willing to admit. When an agricultural chemical is tested for harm, only its active ingredient is tested. However, in real world application, agricultural chemicals also “contain adjuvants, which are often kept confidential and are called inerts by the manufacturing companies.” Some of these adjuvants have proven to be far more dangerous than the active ingredients themselves.

Governments do not require testing of different combinations of pesticides. No one knows what the dangers are. The data does not exist. Governments also do not require testing of the full formulations of pesticides – only the active ingredient. Scientists have discovered that other ingredients in pesticide formulas can be hundreds or thousands of times more toxic than the active ingredient.

In 2012, a group of French researchers explored the effects on human cells of the full formulations of glyphosate-based products. They found that the full formulation of products like Roundup is up to 10,000 more toxic than glyphosate itself which renders acceptable daily intake limits meaningless when those limits are established by governmental authorities based on testing of only the active ingredient. The major adjuvant in Roundup, a compound called POE-15, which the scientists reverse engineered with the aid of mass spectrometry, begins to negatively affect human cellular respiration and membrane integrity at concentrations as low as between one and three parts per million. [26] This was only 24 hours after exposure. An earlier 2007 experiment had demonstrated that Roundup, as opposed to glyphosate by itself, becomes even more toxic after 72 hours. [27]

Shocked by their results, the French scientists followed up their research in 2014 with evaluations of the world’s three major pesticides, herbicides, and fungicides. According to the report they produced, “Fungicides were the most toxic from concentrations 300–600 times lower than agricultural dilutions, followed by herbicides and then insecticides, with very similar profiles in all cell types. Despite its relatively benign reputation, Roundup was among the most toxic herbicides and insecticides tested. Most importantly, 8 formulations out of 9 were up to one thousand times more toxic than their active principles.” [28]

Further research published by the International Journal of Environmental Research and Public Health in 2016 obtained similar results in an examination of glyphosate-based weed killers, explaining, “below their toxicity thresholds, the co-formulants, generally classified as inerts and kept confidential, act as endocrine-disrupting chemicals at levels up to several hundred times below the level at which the declared active ingredient demonstrates the same activity.” [29]

Please leave your comments below. I’d love to hear what you think. Do you eat organic? Why or why not?


Works Cited

[1] Marcin Barański et al., “Higher Antioxidant and Lower Cadmium Concentrations and Lower Incidence of Pesticide Residues in Organically Grown Crops: A Systematic Literature Review and Meta-Analyses,” The British Journal of Nutrition 112, no. 5 (07/15

09/11/received

05/02/revised

05/06/accepted 2014), https://dx.doi.org/10.1017/S0007114514001366.

[2] European Food Safety Authority, “The 2015 European Union Report on Pesticide Residues in Food,” EFSA Journal 15, no. 4 (2017), https://dx.doi.org/10.2903/j.efsa.2017.4791.

[3] Baker, B. P., et al. (2002). “Pesticide residues in conventional, integrated pest management (IPM)-grown and organic foods: insights from three US data sets.” Food Additives & Contaminants 19(5): 427-446.

[4] 2010 – 2011 Pilot Study Pesticide Residue Testing of Organic Produce (US Department of Agriculture – Agricultural Marketing Service, 2012), accessed August 2, 2018, https://www.ams.usda.gov/sites/default/files/media/Pesticide%20Residue%20Testing_Org%20Produce_2010-11PilotStudy.pdf.

[5] Environmental Working Group, “Ewg’s 2018 Shopper’s Guide to Pesticides in Produce™,” Environmental Working Group, 2018, accessed July 12, 2018, https://www.ewg.org/foodnews/summary.php.

[6] 2015 Pesticide Data Program (Pdp) Annual Summary Q&A (US Department of Agriculture – Agricultural Marketing Service, 2015).

[7] Ivan Frernandez, “The Glyphosate Market: A ‘Roundup’,” Frost & Sullivan Market Insight, Frost and Sullivan, 2002, accessed July 13, 2018, http://www.frost.com/prod/servlet/market-insight-print.pag?docid=JEVS-5N2CZG.

[8] Tiziano Gomiero, “Food Quality Assessment in Organic Vs. Conventional Agricultural Produce: Findings and Issues,” Applied Soil Ecology 123 (February 2018 2018), https://dx.doi.org/10.1016/j.apsoil.2017.10.014.

[9] Geoffrey Mohan, “Glyphosate Cancer Warning in California Halted,” The Los Angeles Times, February 27, 2018, 2018, accessed September 24, 2018, http://www.latimes.com/business/la-fi-glyphosate-prop65-story.html.

[10] Geoffrey Mohan, “California Jury Awards $289 Million to Man Who Claimed Monsanto’s Roundup Pesticide Gave Him Cancer,” The Los Angeles Times2018, accessed September 24, 2018, http://www.latimes.com/business/la-fi-roundup-verdict-20180810-story.html.

[11] Emily Sullivan, “Groundskeeper Accepts Reduced $78 Million Award in Monsanto Cancer Suit,” NPR.org, 2018, accessed January 13, 2019, https://www.npr.org/2018/11/01/662812333/groundskeeper-accepts-reduced-78-million-in-monsanto-cancer-suit.

[12] Camila Domonoske, “Monsanto No More: Agri-Chemical Giant’s Name Dropped in Bayer Acquisition,” NPR.org, 2018, accessed Jan 13, 2019, https://www.npr.org/sections/thetwo-way/2018/06/04/616772911/monsanto-no-more-agri-chemical-giants-name-dropped-in-bayer-acquisition.

[13] Dewayne Johnson Vs. Monsanto Company Et Al (SUPERIOR COURT OF CALIFORNIA, COUNTY OF SAN FRANCISCO, 2018).

[14] “Lawyers: Crt Correction of Glyphosate Review Only Tells Half the Story,” Baum Hedland Aristei Goldman PC, 2018, accessed Ocotber 9, 2018, https://www.baumhedlundlaw.com/9-18-journal-correction-monsanto-review/.

[15] Sam; Gillam Levin, Carey, “‘The World Is against Them’: New Era of Cancer Lawsuits Threaten Monsanto,” The Guardian, 2018, accessed October 9, 2018, https://www.theguardian.com/science/2018/oct/07/monsanto-trial-cancer-appeal-glyphosate-chemical.

[16] National Pesticide Information Center, “Imidacloprid,” National Pesticide Information Center, last modified May 2010, 2010, accessed July 12, 2018, http://npic.orst.edu/factsheets/imidagen.html.

[17] US Environmental Protection Agency Office of Pesticide Programs, Chemicals Evaluated for Carcinogenic Potential – Annual Cancer Report 2017 (2017), http://npic.orst.edu/chemicals_evaluated.pdf.

[18] Pesticide Data Program (U.S.) and United States. Agricultural Marketing Service. Science & Technology Programs, Pesticide Data Program Annual Summary, Annual Summary, Calendar Year 2015 (Washington, DC: United States Department of Agriculture, Agricultural Marketing Service, 2016).

[19] Enironmental Working Group (2018). “EWG’s 2018 Shopper’s Guide to Pesticides in Produce™.” Retrieved July 12, 2018, from https://www.ewg.org/foodnews/summary.php.

[20] Pesticide Data Program (U.S.) and United States. Agricultural Marketing Service. Science & Technology Programs.

[21] Sam  Levin, “The Man Who Beat Monsanto: ‘They Have to Pay for Not Being Honest’,” The Guardian, 2018, accessed October 9, 2018, https://www.theguardian.com/business/2018/sep/25/monsanto-dewayne-johnson-cancer-verdict.

[22] B. Sherer Todd et al., “Mechanism of Toxicity of Pesticides Acting at Complex I: Relevance to Environmental Etiologies of Parkinson’s Disease,” Journal of Neurochemistry 100, no. 6 (2007/03/01 2006), accessed 2018/07/13, https://dx.doi.org/10.1111/j.1471-4159.2006.04333.x.

[23] Pesticide Data Program (U.S.) and United States. Agricultural Marketing Service. Science & Technology Programs.

[24] Mingjun Yang et al., “The Insecticide Spinosad Induces DNA Damage and Apoptosis in Hek293 and Hepg2 Cells,” Mutation Research/Genetic Toxicology and Environmental Mutagenesis 812 (2016/12/01/ 2016), https://dx.doi.org/https://doi.org/10.1016/j.mrgentox.2016.11.001.

[25] Doug Wallace, host, “Episode 67: Doug Wallace Talks About Mitochondria, Our Human Origins and the Possibility of Mitochondria-Targeted Therapies,” STEM-Talk, Florida Institute for Human and Machine Cognition, July 3, 2018, 2018, https://www.ihmc.us/stemtalk/episode-67/.

[26] R. Mesnage, B. Bernay, and G. E. Séralini, “Ethoxylated Adjuvants of Glyphosate-Based Herbicides Are Active Principles of Human Cell Toxicity,” Toxicology 313, no. 2 (2013/11/16/ 2013), https://dx.doi.org/https://doi.org/10.1016/j.tox.2012.09.006.

[27] N. Benachour et al., “Time- and Dose-Dependent Effects of Roundup on Human Embryonic and Placental Cells,” Archives of Environmental Contamination and Toxicology 53, no. 1 (2007/07/01 2007), https://dx.doi.org/10.1007/s00244-006-0154-8.

[28] Robin Mesnage et al., “Major Pesticides Are More Toxic to Human Cells Than Their Declared Active Principles,” BioMed Research International 2014 (2014), https://dx.doi.org/10.1155/2014/179691.

[29] Nicolas Defarge et al., “Co-Formulants in Glyphosate-Based Herbicides Disrupt Aromatase Activity in Human Cells Below Toxic Levels,” International Journal of Environmental Research and Public Health 13, no. 3 (02/26

11/02/received

02/15/accepted 2016), https://dx.doi.org/10.3390/ijerph13030264.