Chemicals of Concern – Glyphosate



The use of agricultural herbicides in conventional agricultural farming has an impact on food and crops produced. Debate about the efficacy and safety of certain products and the long-term risk they pose to society and the environment have shadowed herbicide use for decades. In this article, we contribute to this discussion, unpacking the sustainability issues and risks associated with use of herbicides, taking a particular focus on glyphosate, the most widely used herbicide in the world.


Glyphosate in agriculture

Conventional agricultural techniques are heavily reliant on the use of chemical fertilisers, pesticides and herbicides to enhance production and manage farms. Glyphosate is based on glycine, an amino acid, and acts by blocking the production of other amino acids, preventing plants from making proteins, which in turn prevents plant growth, ultimately killing the plant.[1]
Many conventional farms both in Australia and around the globe are reliant on glyphosate products and utilise genetically modified (GM) food crops specially designed to resist herbicides containing the chemical. GM herbicide resistant canola was approved for use in Australia in 2003 and field trials for various other products are being conducted.[2]

Over the years, concerns have been raised about the use of herbicides containing glyphosate. These concerns stem from the widespread use of the chemical and the ongoing potential impacts associated with its use in garden and agriculture products. In recent times, there have been studies published that support an argument for this concern [3] with glyphosate also found in the air and rain in the US by scientists from the US Geological Survey and The School of Public Health, Minnesota. [4]

Commercial use of glyphosate under the product name Roundup began in 1974 with agricultural chemical company Monsanto[i]. [5] Monsanto’s patent for Roundup expired in 2000 and since then glyphosate herbicides have been sold under a variety of brand names by the company as well as other agricultural or garden product manufacturers such as Weedmaster Duo, Zero. The herbicide is also available under more generic brand names such as Glyphosate 450.

In Australia, registered use of glyphosate in a herbicide product like Roundup is only allowed 5-7days before the harvest of crops. The Australian Pesticides and Veterinary Medicines Authority (APVMA) [ii] is responsible for regulation of herbicides and lists approximately 539 registered products containing the chemical glyphosate in Australia [6] with about 20 of these products available for garden use. Glyphosate is commonly used by local councils and local territory governments on public land according to the requirements set by the APVMA.


Environmental risks and safety of use

Properly validated studies have argued both for and against the safe use of glyphosate herbicides over the years.

A European pilot study on glyphosate quoted recently in The Guardian states that recent results show the chemical found in the most widely used weedkiller in the world can disrupt development of genes and bacteria in the gut at what are considered safe doses. The study also found that this chemical of concern has been found at vastly increased levels in the human bloodstream in the last twenty years. [7,8]

One of the author’s of this recent report, Daniele Mandrioli of the Ramazzini Institute in Bologna, Italy, has described the effect of the chemical on gut bacteria. Among other health effects, microbiome disruption has been associated with obesity, diabetes and immunological problems.

Furthermore, controversy has surrounded glyphosate since it was deemed a probable carcinogen in a report published by the International Agency for Research on Cancer (IARC) in March 2015. In contrast with this finding, the European Food and Safety Authority (EFSA) concluded in October 2015 that ‘there is very limited evidence for an association between glyphosate based formulation and non-Hodgkin lymphoma[iii], overall inconclusive for a casual or clear associative relationship between glyphosate and cancer in human studies’. [9,10]
The results of the pilot study referred to the in The Guardian were set out in the journal Environmental Health in late May 2018. [11] The authors have slated a comprehensive long-term study to follow that will attempt to provide an understanding of the long term risks of glyphosate use.


Why is this important to Investors?

Large corporations involved in the production and distribution of chemicals are exposed to environmental and legal risks if chemicals of concern, such as glyphosate, prove to be unsafe. Investors need to be aware:

  • of their own exposure to such risks within their portfolios, and
  • of the company or companies responsible for that risk, or the ultimate parent entity that assumes that risk.

Glyphosate has recently been relicensed for use in Europe after winning a five-year lease with the European Union despite public health risks raised by studies such as the one referred to above, ensuring the use of this particular herbicide, as well as herbicides in general, will continue to be an issue investors should watch.



Interested in discussing this issue further? Feel free to get in touch.

CAER has data available on glyphosate and other chemicals of concern, as well as information on how companies are managing their associated risks.




[i] Monsanto is a US company that is merging with the German company Bayer in a USD $63 billion (EUR $56b) deal in which Monsanto’s name will be dropped. [12]

[ii] The APVMA is responsible for this on a federal level in Australia, with legislation in practical terms acting as Commonwealth laws rather than state laws. See [Accessed, 19/06/2018]

[iii] Non-Hodgkin Lymphoma is a form of cancer of the blood that effects the lymphatic system.



[1] National Pesticide Information Center website: [Accessed, 30/05/2018]

[2] SBS News website, Factbox: GM Foods in Australia, [Accessed, 19/06/2018]

[3] Nelson, Arthur, ‘Glyphosate shown to disrupt microbiome at safe levels, The Guardian, [Accessed, 23/5/2018]

[4] Chang F-C, Simcik MF,Capel PD. ‘Occurrence and fate of the herbicide glyphosate and its degradate aminomethylphosphonic acid in the atmosphere. Environmental Toxicology and Chemistry 30, p548-555 (2011) [Accessed, 12/5/2018]

[5] Benbrook, Charles, M. ‘Trends in glyphosate herbicide use in the United States and globally, p1, (2016): [Accessed, 12/5/2018]

[6] Australian Pesticides and Veterinary Medicines Authority (APVMA) Website: [Accessed, 12/5/2018]

[7] Nelson, Arthur, ‘Glyphosate shown to disrupt microbiome at safe levels, The Guardian, [Accessed, 23/5/2018]

[8] Park, Alice ‘A weed killer is increasingly showing up in people’s bodies, Time, [Accessed, 19/6/2018]

[9] Portier CJ, Armstrong BK, Baguley BC et al. Differences in the carcinogenic evaluation of glyphosate between the International Agency for Research on Cancer (IARC) and the European Food Safety Authority (EFSA). (2016) Journal of Epidemiology and Human Health 70, 741-745. [Accessed, 30/5/2018]

[10] Sass J. 2017. [Accessed, 30/5/2018]

[11] Landrigan, P.J., Belpoggi, F. The need for independent research on the health effects of glyphosate-based herbicides, [Accessed, 08/06/2018]

[12] Böhme, Henrik, Opinion: The Bayer-Monsanto merger, Deutsche Welle, 7/06/2018, [Accessed, 08/06/18]

Konrad Knerr

Author: Konrad Knerr