1. What is glyphosate?

It is a complex molecule containing atoms of carbon, oxygen, nitrogen, hydrogen and phosphorous.

Full name: N-(phosphonomethyl)glycine
Chemical formula: C3H8NO5P
Break down product: AMPA

2. What are its chemical properties?

It is a phosphonic acid. It is an organophosphonate.

Glyphosate has a negative charge. i.e. It is a negative ion. This means it readily combines with positive metal ions. For this reason it is called a chelating agent. Elements which commonly occur as positive ions include calcium, magnesium, copper, cadmium and manganese.

Glyphosate is readily soluble in water.

3. What is Roundup?

Roundup is a weed killer patented by Monsanto circa 1972. It contains glyphosate and other chemicals called adjuvants. On its own glyphosate does not kill weeds. The additives, including surfactants, allow the glyphosate to enter the plant’s biological pathways. Glyphosate blocks the shikimate pathway. This stops the production of several vital amino acids.

It is a systemic weed killer so reaches all parts of the plant from the roots to the flowers to the seeds.

It kills almost all green plants. Some plants are thought to be developing a resistance to it.

Monsanto have genetically modified some plants so that they can tolerate Roundup. These are called Roundup Ready (RR) crops. Soya and oil seed rape have both been modified in this way. Their RR varieties are grown extensively in North and South America. They are currently banned in Europe.

4. What is glyphosate used for?

The first patent for glyphosate was granted in the 1950s. This was for use as a water pipe descaling agent. Glyphosate’s water soluble and chelating properties mean it is very effective at removing calcium, magnesium and other metallic deposits from water pipes.

The second patent was to Monsanto in the early 1970’s for use as a weed killer. It was claimed that glyphosate does not harm humans as the shikimate pathway is absent in our bodies. We get the vital amino acids formed in the shikimate pathway from eating plants. Monsanto also claimed that glyphosate does not significantly harm soil or the environment.

The third patent was granted to Monsanto in 2010. This was for glyphosate to be used as an antibiotic. Some bacteria do contain the shikimate pathway and so are destroyed by exposure to glyphosate.

This fact negates the claim about its safety for humans as it adversely affects the beneficial bacteria in our guts.

Glyphosate herbicides are now used extensively as a desiccant in farming. They are sprayed when the crop is fully grown, a couple of weeks before harvesting. The sprayed plant will cost the farmer less to dry. This is how a lot of glyphosate gets into our food. It is not removed by washing or cooking.

5. How does glyphosate kill plants?

The shikimate pathway is used to create essential amino acids. Without these amino acids, vital processes, such as photosynthesis, cease in the plant.

The plant is deprived of vital micro nutrients by glyphosate’s strong chelating properties. This weakens the plant’s immune system.

Colonel Don Huber (Emeritus Professor (plant physiology) at Purdue University USA) has done a lot of research on the effects of glyphosate on plants and the soil.

6. Which government agencies regulate and grant licences for glyphosate?

In the UK the regulating authority is the Chemicals Regulation Division (CRD) based in York. The CRD is part of the HSE. It is also closely linked to Defra.

The appeal committee of the European Commission extended glyphosate’s licence for five years in 2017. The key change that allowed this was the change in position of Germany to supporting the extension. It is thought this decision is related to the acquisition in 2017 of Monsanto by the German chemical giant Bayer for $66bn.

7. What types of test are done to establish the safety or otherwise of glyphosate products such as Roundup?

Roundup is not tested directly on humans for obvious reasons. In any case it would be impossible to find a control group in the population that is not exposed to glyphosate.

The main testing method is experiments on animals. These are almost always short term/high dose experiments. Humans are usually exposed to glyphosate in small doses over many years.

Experiments are also done on tissue/cell cultures in test tubes and petri dishes. Specific human cells are exposed to diluted glyphosate.

Epidemiology research involves studying the health of the sections of the population that are most exposed to Roundup type herbicides. These groups are usually farm workers or amenity users of herbicides such as council employees.

8. Why does the ECHA and the EFSA think glyphosate is safe?

The European Chemicals Agency (ECHA) and the European Food Safety Authority (EFSA) are European agencies which advise the European Parliament and EU Commission on pesticide, chemicals and food safety issues.

When reviewing glyphosate’s safety they only considered studies which tested glyphosate alone as opposed to the commercial product, such as Roundup, which contains a mixture of chemicals. This has been compared to testing a gin and tonic for alcohol and only testing the tonic.

There is irrefutable evidence that the commercial product is much more toxic than glyphosate on its own. The ECHA have said that it is up to member states to test commercial products. I know of no evidence that the CRD have done this for Roundup.

The EFSA and the ECHA reports were produced by anonymous authors. They also used unpublished, industry sourced, reports. Some of these reports have not been made publicly available.
reference (This is a big document but the conclusion is short and succinct)

9. Why do the WHO (IARC) think glyphosate herbicides are probable carcinogens to humans and almost certainly carcinogenic to animals?

IARC looked at research that had been done using commercial formulations containing glyphosate. They also looked at epidemiological studies.

All voting members of the panel put their name to the report. Only panel members who did not have financial links to the manufacturers were allowed to vote. All the material they considered had been published.

They concluded that the evidence was conclusive that glyphosate is a carcinogen to animals. However, despite this they put glyphosate in the “probable” carcinogen (Group 2A) for humans as they said they did not have enough evidence to put it in the Group 1 category.
reference (This is also very long. Conclusion on page 78.)

10. With which human health problems has glyphosate been linked?

This list is a long one as the evidence is very strong that as well as being a carcinogen glyphosate is a mutagen, teratogen, antibiotic and a hormone disrupting chemical.

Health problems linked to glyphosate include non Hodgkin lymphoma, birth defects, diseases of the gut, autism, kidney disease and various neurological problems.

Glyphosate has been detected in breast milk.

11. What is the evidence that glyphosate herbicides can have adverse effects on human health?

Two studies of farm workers – one in Canada and one in Sweden – showed that exposure to glyphosate increased the risk of non Hodgkin lymphoma.

In Colombia certain areas were sprayed with Roundup from aircraft. This was done to destroy coca production which is used to make cocaine. The health of people in these areas was compared with nearby communities where spraying was not done. The same has been done in areas of Argentina where RR soya is aerially sprayed. There is evidence that birth defects, neurological damage and skin problems have significantly increased after exposure to glyphosate herbicides.
reference (“The World According to Monsanto”, by Marie-Monique Robin, page 265)

12. Why did a court in California award damages of $289million against Monsanto in August 2018?

The court awarded the plaintiff, Dewayne Johnson, $39mn in damages as they said exposure to Monsanto’s Roundup had “substantially contributed” to his developing non Hodgkin lymphoma.

Monsanto were forced by the court to reveal internal emails. After studying these the jury decided that Monsanto either knew or should have known their product was “dangerous”. Monsanto had misled the public by, among other things, ghost writing articles in scientific journals – these were presented as being written by independent people.

The court concluded that Monsanto had acted with “malice or oppression” towards the public and awarded $250mn in punitive damages against them. This amount was reduced to $39mn on appeal. I don’t think Monsanto have yet paid out any money to the plaintiff.

13. What protective clothing should people who spray glyphosate, using a backpack, wear?

Monsanto’s own product guide for Roundup says “Minimum protective clothing when spraying is a protective coverall, rubber gloves and rubber boots”. The protective coverall is a disposable, usually white, overall. I think Dewayne Johnson used this protective clothing. I would add a facemask as glyphosate will be inhaled during spraying.

14. What do Newcastle City Council employees wear when spraying glyphosate?

I have never seen an NCC employee wearing any of these things when backpack spraying. They will be in their normal work clothes, have a high vis jacket and be wearing leather (porous) gloves.

I have drawn the council’s attention to the totally inadequate protective equipment worn by their employees numerous times.

If NCC did insist on proper protective clothing they would be inundated with complaints from the public about their spraying a chemical that needs this sort of clothing outside houses and around parks, schools etc. Councillors would then be forced to change to safe methods of weed control.

15. Where do NCC council contractors on mounted machines spray?

They spray pavements, kerbs, path edges and hard surfaces generally.

The machine operatives also carry a handheld lance that they point at weeds their machine can’t reach. They control the machine with one hand and their feet and simultaneously spray with the lance in their “free” hand - while the machine is moving. It is, of course, unsafe not to have two hands on the control wheel of a potentially lethal vehicle which goes on the pavements.

16. Why is spraying on hard surfaces particularly environmentally harmful?

Roundup that lands on a hard surface will not be absorbed. Some will evaporate which is why glyphosate is present in the air. The dry residue will be washed into the drains and reach watercourses, ponds etc.

Glyphosate breaks down slowly in water and is very harmful to many creatures that live wholly or partially in the water. Amphibians such as frogs are in decline at an alarming rate globally. Tadpoles are particularly susceptible to glyphosate.

The authorities are aware of this and prohibit (but don’t enforce) spraying directly onto pavements. In theory the machines should only spray growing plants – they don’t. However, it is permissible to spray directly onto kerbs. As there are many miles of kerbs in Newcastle the overall harmful effect of this dispensation is enormous.
reference (pdf)

17. Which UK local authorities have adopted pesticide free methods of weed control?

Hammersmith and Fulham in London are completely pesticide free. So are Lewes in Sussex, Glastonbury and Wadebridge in Cornwall. Croydon has recently banned pesticide use in their parks and public green spaces.

Many local authorities in the other parts of the UK use very little pesticide and the visible effects are minor. I put Cornwall County Council and Sefton (Lancashire) in this category.

18. How do you control weeds without using pesticides?

There is no magic bullet to replace the use of herbicides. A combination of methods is required:

Foamstream, produced by Weedingtech, is used by Lewes, Hammersmith and Glastonbury councils. A mounted machine supplies hot foam through a hose. The targeted plants are killed quickly by the heat. Glyphosate sprayed plants die slowly – they don’t change colour for over a week after spraying. Foamstream will also remove chewing gum and graffiti.

Nilfisk produce versatile machines with brushes that will remove weeds and collect the debris.

Mechanical methods such as strimming can be used.

In many places weeding is unnecessary and the remaining weeds benefit insects and hedgehogs.

19. How much would it cost NCC to change to pesticide free methods of weed control?

At a meeting of NCC’s Scrutiny committee the spokesperson claimed that it would be six to ten times as expensive to use safe methods of weed control. This was based on a study done in Kent (Thanet). This figure is not credible. It is inconceivable that the local authorities that have gone pesticide free spend this much more on weed control.

Lewes council say using Foamstream is a bit more expensive but they can recoup some of the cost by hiring out their machine in periods when they are not using it. Also they can do the work in any weather and at any time of year without giving the staff special training.

I am sure Hammersmith and Fulham council would advise NCC on the real cost of changing to safe methods.

20. Why are council officers reluctant to change to safe methods of weed control?

It is hard to know. The change would need careful preparation, planning and management. The public would need to have the reasons for the change explained to them.

I suspect that if NCC were to announce that they are going pesticide free they might feel that they were letting the “glyphosate is safe” side down. i.e. all their neighbouring councils.

Inertia is certainly a factor.

21. Which organisation represents the pesticide manufacturers to amenity users of pesticides?

The Amenity Forum is the organisation that represents the producers to amenity users of pesticides such as local authorities. It is partially funded by the manufacturers. It sees one of its roles as countering any adverse publicity that products such as Roundup may get. This is usually means rubbishing the latest researcher who has produced a report showing a harmful effect(s) of glyphosate or other pesticide.

I was on their email list for a while. When I suggested that they publish a representative range of views instead of just pro industry ones (as they claim to be a” forum”) they removed me from the email list.

22. Which organisations would advise NCC on how to change to safe methods of weed control?

Pesticide Action Network UK would willingly offer advice. Weedingtech would obviously advise on how best to use their product. I am sure pesticide free councils would be only too happy to discuss their change-over teething problems.

23. What do the public think when told that glyphosate is used extensively to manage public land in the city?

The great majority of the people I speak to hate the sight of sprayed off vegetation around the city and deplore the fact that they are forced to be exposed to harmful chemicals. Many people are now aware of the issue as it has been in the news recently. A lot of people are shocked that their local authority should be using unsafe chemicals to manage public land when harmless alternatives are available.

Talking to people outside the Civic Centre I know that there are many people who work in there who would also like to see Newcastle become a pesticide free city.

Practically the only defenders of the current chemical methods of weed control are a few people who work in the land management section of the council.

24. Is there any evidence that glyphosate herbicides are contributing to the rapidly falling populations of butterflies, bees and frogs?

Research from University of Texas and from China has shown that glyphosate weakens bee’s immune system and impairs their cognition. This is because glyphosate is systemic and is in the flowers of sprayed plants. It damages the bee’s healthy gut bacteria due to its anti-biotic properties.

The evidence that they harm frogs is very strong. Good research has been done by Dr Rick Relyea et al. He showed in a carefully designed experiment that amphibians generally and tadpoles in particular are sensitive to glyphosate.

I am sure that spraying glyphosate directly onto butterflies will kill them – it would blind them for a start. It has also been shown that arthropods (spiders etc) are harmed by the dry residue left on plants after spraying. I am sure the same applies to butterflies and caterpillars which land on or feed on recently sprayed plants.

There is a strong correlation between the decline in populations of bees, butterflies and amphibians and the steady increase in the amount of glyphosate used in agriculture and by the amenity sector.

25. Why are some countries such as France and Germany imposing bans on the use of pesticides to manage public land?

The public and politicians in many European countries seem much more aware of the potential of pesticides to harm humans and nature. For instance President Macron has clearly studied the issue of glyphosate herbicides. He would like to see them banned for agricultural purposes in the future. His administration has imposed a ban on glyphosate herbicides being used in gardens from the start of this year.

26. Why did El Salvador and Sri Lanka impose total bans on glyphosate use?

These countries banned glyphosate herbicides because they both experienced epidemics of a fatal kidney disease - CKDu. Some of the usual causes of kidney disease (diabetes and high blood pressure) were ruled out.

The hypothesis is that workers in these countries are exposed to heavy metals in the water they drink. When they spray glyphosate, wearing clothes similar to an NCC employee, the glyphosate entering their body combines with metals such as cadmium, manganese and copper to form stable compounds which destroy their kidneys.

Strong support for this theory is that some parts of Sri Lanka, where farming methods and the soil are similar, have not had a CKDu epidemic. In these regions the use of glyphosate herbicides has been banned for a long time. The ban was enforced in Tamil (separatist group) dominated areas. Apparently another thing you can do with glyphosate is make a bomb out of it. The 26 year civil war ended in 2009 so perhaps these areas are allowed to use glyphosate now. The damage done to the kidneys by glyphosate is quite a slow process.

Although our water does not contain as many heavy metal ions as that used by the Sri Lankan farmers small amounts are present in our drinking water. The same kidney damaging process could be taking place, more slowly, across Europe. There has been a rise in kidney disease in the west over the last 20 years.

John Wilson, Feb 2019