Can Glyphosate Affect Our Health in the UK?

A recent EU vote on the use of glyphosate granted a new five-year licence1 and since the UK voted for, it’s unlikely that even after Brexit we will see a ban on glyphosate use in the foreseeable future. So, what’s the big issue with glyphosate?

Glyphosate is the active ingredient in the weed killer/herbicide Roundup. If you haven’t heard of it, you’re probably not a farmer or a gardener, but it may still be relevant to you, especially if you’re keen on promoting your health.

Glyphosate is classified as a probable carcinogen by the World Health Organisation2, on the basis that it caused tumours in mice. However, glyphosate isn’t used on its own but formulated with other chemicals, as in Roundup. Both glyphosate alone and co-formulants have been found to be endocrine disruptors i.e. hormone disruptors3. More specifically, the activity of the enzyme aromatase is decreased. Aromatase is a key enzyme involved in the balance of our sex hormones. The levels of glyphosate needed to affect aromatase are below the levels considered toxic – by one-third of the dilution used in agriculture, if you want to know. This combination of glyphosate and other chemicals used in Roundup is referred to as glyphosate-based herbicides (GBH). GBH (think ‘grievous bodily harm’) is an endocrine disruptor! Notice the irony, anyone?

Besides tumours, other health effects from chronic exposure to very low levels of glyphosate, (i.e. below the regulatory lowest observed adverse effect level) can cause birth defects, kidney disease and liver disease4. Based on animal and in vitro (test-tube/petri dish) studies, there is also evidence of potential reproductive disorders, neurotoxicity, cardiovascular problems and allergies.

To what extent are UK residents affected by glyphosate? In a Friends of the Earth Europe independently commissioned laboratory survey of urine samples, it showed that in the UK 70% of people had traces of glyphosate in their urine5. Count me out, please!

Glyphosate also suppresses our gut microbes’ ability to synthesis amino acids6, some of which are used towards making our neurotransmitters like tyrosine for dopamine – our motivational neurotransmitter – and tryptophan for serotonin – our ‘feel happy’ neurotransmitter. It also suppresses our liver’s capacity to do its job of detoxifying toxins, by suppressing cytochrome P450 enzymes6 involved in Phase 1 of detoxification. So, glyphosate can affect our health in many ways.

The soil’s health is affected adversely by glyphosate and Roundup too. One study7 found the dose that caused death to 50% (LD50) of a fungus called Aspergillus nidulans, (a marker of health for agricultural soils) corresponded to a dilution 100 times less than that used in agriculture. This means glyphosate and Roundup is affecting the health of our soil’s microbes, and therefore the safety of our food from plants grown in Roundup-contaminated soils, according to the authors. The multiple effects of Roundup in plants included impaired growth and cell disturbances (especially at the level of energy and respiratory metabolism), something not seen in animal cells. Soil ecosystems could potentially be adversely affected. Moreover, it’s not only the soil microbes that are affected but glyphosate-based herbicides reduce the activity and reproduction of our humble earthworms too8. We need them to aerate the soil and improve its structure to keep it healthy.

But wait a minute, glyphosate isn’t just used as a weed killer. It’s even used as a crop desiccant e.g. before harvesting wheat9. It’s claimed to improve harvesting efficiency. This means there’s likely to be a higher residue when glyphosate is applied to moist grain. There has been an issue with glyphosate residue in almost two-thirds of wholemeal bread, according to tests by the Defra Committee on Pesticide Residues in Food10. Recently the issue seems to have gone quiet, though. In other words, following up on any links drew a blank (i.e. they no longer exist).

A newer concern about glyphosate is that, along with other herbicides, it has been found to promote antibiotic resistance to pathogenic bacteria like E. coli and Salmonella11. The levels of herbicide residue found in food products was higher than the maximum levels set by the Codex Alimentarius Commission12, which regulates the maximum exposure from active ingredients of herbicides in food for our safety. You might just want to consider the effects of eating glyphosate-residue-laden food on your gut microbes!

Is there anything else we might be concerned about regarding glyphosate? Maybe. The use of genetically modified (GM) crops or genetically modified organism (GMOs) could also be an issue linked to glyphosate. These GM/GMO plants are now used in the UK as animal feed, such as GM soy and GM maize13. That means there may be residues of glyphosate left in the meat fed GM soy, whether we’re talking cattle or poultry.

However, not all supermarket meat or poultry is affected by GMOs. My local supermarket, Waitrose, for example, avoids them in its ‘own brand’ foods14. But take care not to be caught out if you want to avoid glyphosate residue or even GM-tainted food. Some meat or poultry with glyphosate residues that are not ‘own brand’ at Waitrose may still be on the shelves for you to buy unawares. I won’t name any brand, but some detective work and personal communication means I don’t buy certain brands anymore for health reasons.

So, what are we to do? If you want to be safe, choose organic. Plain and simple.

References

• 1. BBC News (2017). EU settles dispute over major weedkiller glyphosate. BBC News. [online] Available from: http://www.bbc.co.uk/news/world-europe-42135437 [Accessed 28 November 2017].
• 2. WHO, 2016, World Health Organization, International Agency for Research on Cancer, (2016). IARC Monographs Volume 112: evaluation of five organophosphate insecticides and herbicides.
• 3. Defarge, N., Takács, E., Lozano, V.L., Mesnage, R., Spiroux de Vendômois, J., Séralini, G.-E., et al., (2016). Co-formulants in glyphosate-based herbicides disrupt aromatase activity in human cells below toxic levels. International Journal of Environmental Research & Public Health. 13(3), 264.
• 4. Mesnage, R., Defarge, N., Spiroux de Vendômois, J., Séralini, G.E., (2015). Potential toxic effects of glyphosate and its commercial formulations below regulatory limits. Food and Chemical Toxicology. 84, 133-153.
• 5. FOEE, (2013). Human contamination by glyphosate. Friends of the Earth Europe. [online] Available from: https://www.foeeurope.org/sites/default/files/publications/foee_4_human_contamination_glyphosate.pdf [Accessed 28 November 2017].
• 6. a. b. Samsel, A. & Seneff, S., (2013). Glyphosate’s Suppression of Cytochrome P450 Enzymes and Amino Acid Biosynthesis by the Gut Microbiome: Pathways to Modern Diseases. Entropy. 15(4), 1416-1463.
• 7. Nicolas, V., Oestreicher, N., Vélot, C., (2016). Multiple effects of a commercial Roundup® formulation on the soil filamentous fungus Aspergillus nidulans at low doses: evidence of an unexpected impact on energetic metabolism. Environmental Science & Pollution Research. 23(14), 14393-14404.
• 8. Gaupp-Berghausen, M., Hofer, M., Rewald, B., Zaller, J.G., (2015). Glyphosate-based herbicides reduce the activity and reproduction of earthworms and lead to increased soil nutrient concentrations. Scientific Reports. 5, 12886.
• 9. HGCA, 2008. Pre-harvest glyphosate application to wheat and barley. [online] Information Sheet 02/Summer 2008.
• 10. Soil Association, 2016. Not in our bread. [online] Available from: https://www.soilassociation.org/our-campaigns/not-in-our-bread/ [Accessed 28 November 2017].
• 11. Kurenbach, B., Marjoshi, D., Amábile-Cuevas, C.F., Ferguson, G.C., Godsoe, W., Gibson, P., Heinemann, J.A., (2015). Sublethal Exposure to Commercial Formulations of the Herbicides Dicamba, 2,4-Dichlorophenoxyacetic Acid, and Glyphosate Cause Changes in Antibiotic Susceptibility in Escherichia coli and Salmonella enterica serovar Typhimurium. mBio (Journal published by the American Society for Microbiology). 6(2): e00009-15.
• 12. Kurenbach, B. Gibson, P.S., Hill, A.M., Bitzer, A.S., Silby, M.W., Godsoe, W.G., Heinemann, J.A., (2017). Herbicide ingredients change Salmonella enterica sv. Typhimurium and Escherichia coli antibiotic responses. Microbiology. 163:1791–1801.
• 13. Jamieson, S., (2016). Majority of supermarket meat comes from animals fed on GM crops. [online] Available from: http://www.telegraph.co.uk/news/earth/agriculture/food/12171193/Majority-of-supermarket-meat-comes-from-animals-fed-on-GM-crops.html [Accessed 30 November 2017].
• 14. Waitrose, (2017). Genetically modified products. [online] Available from: http://www.waitrose.com/home/inspiration/about_waitrose/the_waitrose_way/gm.html [Accessed 30 November 2017].