Glyphosate. Weed killer. Probable carcinogen. The active ingredient found in widespread products. You may even have some in your garden shed. It is found in most herbicide products in the UK (including Roundup) and accounts for a quarter of global herbicide sales.
In a game changing ruling yesterday, agro-chemical company Monsanto have been ordered to pay damages of $289 million to an American man dying of non-Hogkin lymphoma (a type of blood cell cancer) to which glyphosate formulations (from his many years spraying as a groundskeeper) have been attributed as the probable cause. In addition, the Jury, after being presented with extensive scientific research, found Monsanto to have been negligent having known about the potential effects for years.
So what is it? Glyphosate is a herbicide that can be used on broad-leaved plants and grasses. It blocks enzymes involved in the Shikimate Pathway, a vital process for growth in plants and some microorganisms. Glyphosate is a broad-spectrum herbicide which means it will kill most plants. In most herbicide products glyphosate it is in formulations with other chemicals that may be even more harmful.
So why is it dangerous? In-lab studies have linked glyphosate to cancer, particularly non-Hogkin lymphoma. It has also been linked to developmental and reproductive effects in high doses. In 2015 the World Health Organisation (WHO) International Agency for Research on Cancer (IARC) concluded that glyphosate was “probably carcinogenic” from a hazard perspective. It will also most certainly make you ill if you breathe it in or ingest it.
And what about environmental effects? Glyphosate kills or injures most plants and it binds to some kinds of soil making it persistent for up to six months, and in other soils it may leach into waterways. It is used for agriculture and by gardeners and groundskeepers. If you live in the UK you might notice that at the edge of paths and around the base of fences/trees look brown and crispy – usually because they’ve been sprayed with it.
This 2013 report by Friends of the Earth (FOE), collates much of the existing research into the environmental effects. Like with humans and pet animals, exposure to glyphosate on or just after application will likely make wildlife ill. Toxic and reproductive effects have also been shown in a number of species.
In the longer term, environmental effects may be as a result of ecological imbalance due to removal of plants. There are some specific cases highlighted in the FOE report, such as the monarch butterfly in North America, whose decline was linked to glyphosate as the caterpillars are dependant on common milkweed – a species controlled with the herbicide. There may also be some implications for the community of microorganisms in the soil as they undergo similar growth processes – glyphosate may increase growth in some species and decimate others.
A statement of concern regarding glyphosate by a number of leading scientists was published in the Journal of Environmental Health in 2016, the statement reviews the existing literature on both health and environmental effects and sets out a number of concerns and recommendations. The statement suggests that due to the health and environmental concerns and their increased use, common commercial formulations of glyphosate based herbicides (GBHs) should be prioritized for inclusion in government-led toxicology testing programmes.
More recently and as a result of requests from the IRAC, the Environmental Protection Agency (EPA) and growing public concern, the US Department of Health and Human Services National Toxicology Program (NTP) has begun to undertake its first ever tests on GBHs, results of the NTP are beginning to be published with further results coming in 2019. Mike DeVito, acting chief of the NTP Laboratory, told the Guardian in this article in May “We see the formulations are much more toxic. The formulations were killing the cells. The glyphosate really didn’t do it”.
In Europe, after lengthy and often non-committal discussions, in December 2017 the European Commission renewed the approval of glyphosate for a period of 5 years. The European Food Standards Agency (EFSA) is also continuing its ongoing review of the existing Maximum Residue Levels (MRLs) – the highest level of a pesticide residue that is legally tolerated in or on food or feed.
One thing is for sure yesterday’s landmark ruling is certainly food for thought, Monsanto have stated that they intend to appeal, but they are also reportedly facing up to 4000 similar cases. The issue of GBHs is certainly one to watch as more research is published and further legal proceedings come to fruition. Is this the beginning of the end for one of the worlds most widespread herbicides?