Travelling in France we visited the stunning, medieval Chateau de Castelnaud. The heavy ancient walls surrounding the castle were 6 to 8 metres high. A well for water, inside the walls was covered with a roof. The purpose of the roof it was explained, was to protect the water source during sieges. During this time, a trebuchet could be used to fling rotting carcases over the walls, in the hope that a beast would land in the castle’s only drinking source. The inhabitants of the castle could only last a matter of days if the water was putrid.
The quality of our drinking water has always been critical to our long term health.
Thoroughly assessing the pesticides in our drinking and ground water, and understanding what levels cause harm, is common sense. But our governments and the assessment agencies continue to dismiss the independent scientists who have determined that the current levels the agencies declare are safe, and that we are now exposed to, are, quite simply, not safe.
The three agencies that conduct the toxicity assessments that establish current permitted levels of pesticide exposure are the US Environment Protection Agency (EPA), the European Food Safety Assessment Authority (EFSA) and the World Health Organisation. Our governments refer to these agencies to establish maximum levels of pesticides in our diet.
Conflicts of Interest in assessment agencies
But there are problems – massive conflicts of interest in the assessment process that result in compromised results.
Internationally, every study held by these assessment agencies and our governments that give us our pesticide ‘acceptable daily intake’, our ADI (or if you are in the US, your reference dose, RfD) - is established using a private corporate study. For example, the companies that supply these critical studies for glyphosate, the active chemical in Roundup herbicide are Monsanto, Cheminova and Syngenta.
Roundup, the formulation that independent scientists are starting to call ‘the world’s most significant environmental toxin’.
When did these agencies establish that corporate science was safer than science produced in the public’s interest? Safer than public domain science?
These private corporate studies are hidden by confidentiality agreements between our assessment agencies and the large corporations that actually make and sell the stuff.
Not disclosed to the public or peer reviewed and available to public health professionals to examine.
As a result, the World Health Organisation hasn’t bothered to set a level for glyphosate in drinking water, because it occurs ‘in drinking-water at concentrations well below those of health concern’. 
The WHO science comes from the same corporations that depend on these very assessments to declare ‘low toxicity.’
Chillingly, or curiously, depending on your view, every study that contributes to the established US EPA drinking water level - 0.7ppm (700 μg/L) - is by Monsanto. The study that sets the ADI for the World Health Organisation for glyphosate (0.3mg/kg bw/day) - is by Monsanto.  This study enabled the WHO to arrive at a ‘health-based value of 0.9 mg/l’. The WHO ADI study is also private, unpublished and thirty-three years old. Therefore it is not available to public sector health professionals to review.
A corporate study produced by the same organisation that produces and sell the stuff, provides the excuse by the World Health Organisation to not establish a minimum level of exposure of a pesticide in our drinking water.
Isn't this wrong?
Shouldn’t independent scientists have the responsibility for assessing whether Roundup is a ‘health concern’ or not? In the 21st century, with modern scientific knowledge at their fingertips.
Europe is a little more cautious – they have a generic level that no pesticide may go above - 0.1 µg/l (100 ng/l or 100ppb) which is 7000 times lower than the USA.  The US sets their glyphosate level at parts per million. Europe sets theirs at parts per billion. Yikes.
Yet still, independent scientists Seralini et al 2014, have found that glyphosate affects us at half the European dose. A French team used a dilution of 0.1ppb of the Roundup formulation, which resulted in a concentration of glyphosate in this mix at 50ng/L – 50ppb. Tumours resulted, even though it wasn’t a cancer study.
It does get a bit complicated – sometimes it is easier to bury our heads in the sand.
This study is highly controversial - mainly because it shows damage at the levels we are exposed to. It was retracted. Then republished. 
This study also revealed that the studies held with the WHO, US EPA and EU are too short term - they do not reveal the long term effects of the full formulation. Yet Roundup is the complete mix our babies ingest, the mix our kids directly eat. The cynics tend to forget that.
It is interesting to note that the level of Roundup in US drinking water is permitted to be 14,000 times higher than what was found to be toxic in this study. Crazy stuff.
Think about the consequences for GMO and monocrop agriculture if this study was actually accepted by the big agencies..... because permitted Roundup residues on most of our staple crops (including wheat) have increased astronomically in the last decade.
It would entail a pretty significant rewrite of crop management.
So what residue levels are scientists are finding all over the world and how do they compare?
France has detected levels in ground water of 0.17 µg/L in Picardie , Spain 200 ng/L .  Good on France for actually testing as procedure – I am not sure how many other countries do this. The Spanish result came from an individual research study.
Moms Across America reported: 'In this initial testing phase 21 samples of drinking water were tested for glyphosate from across the Unites States individually by Moms Across America supporters.
13 of the samples contained glyphosate levels of between 0.085 ug/l and 0.33 ug/l. This is well below the levels found in both urine and breast milk but is still cause for concern, as the European (EU) maximum allowed level for glyphosate in drinking water is 0.1 ug/l.'
But because of the fact that glyphosate is classified as ‘not really worth testing’ – most countries simply don’t test ground water, not even my home, New Zealand.
Do people realise this? Especially when the residues on our food have increased massively as well. There is a cumulative effect that is simply not studied.
Our growing ‘non-communicable’ illness load.
We now spray our cereals, our wheat, barley and oats, with Roundup before harvest, and there are over 80 herbicide tolerant, higher residue Roundup Ready GMOs in our food.
Our bodies are carrying a higher cumulative load than ever before. And our governments simply quote the WHO levels and declare current residues are safe. As the New Zealand food safety minister did this month, when reviewing a public petition to remove pesticides in baby food and bring our legislation in line with Europe.
A 2013 study found glyphosate levels detected in urine samples across Europe.  Urine levels of city workers in Berlin, Germany in a 2011 study, found 'glyphosate in all urine samples at values ranging from 0.5 to 2 ng glyphosate per ml urine (drinking water limit: 0.1 ng/ml)'.  It was surprising - city workers had never before been considered to hold levels of glyphosate based herbicides before. Their exposures were considered insignificant.
I believe people in cereal growing regions with higher rainfall, like Aberdeen, Manitoba, Canterbury (NZ), Amiens, Maastrich and Minnesota, are especially vulnerable. Their soils and cereals carry higher loads of pesticides to compensate for the higher weed, fungal and insect growth that is a result of all that encouraging rain. They are the frogs in the slow warming pot.
These regions all carry higher load of diseases associated with gut dysbiosis. Look at their excellent mental health services, often the best in the country. There’s millions committed to investigating the ways our genes work. Not so much funding is directed to the environmental triggers and toxins that tip us into sickness and ill health.
We are only starting to understand the gut-brain connection. But there is little or no public funding of the environmental triggers that cause permeable gut and reduced microbiota. Of the effects of prolonged exposure at these low doses.
That is called preventative medicine.
The areas our agencies 'miss' when they assess our pesticides.
Many of the critical studies that research effects, don’t conduct research for a sufficient time period. These studies don’t reveal long term effects like organ damage and tumour growth.
It’s really important to understand that the developmental studies held with these agencies, researching malformations and behavioural problems DO NOT dose the mother in the lead up to pregnancy or in the first 6 days. The first trimester if you are a rat or mouse mother. The embryo never sees the toxin.
The official studies held with the WHO, EPA and EFSA never test the stronger formulation of Roundup. Ever. Roundup has been found to be over 100 times more toxic than glyphosate. The added ‘stuff’ that makes it stronger, the adjuvants, aren’t even monitored or assessed. Yet it is the complete formulation that is poured on our food (yes, on our food), and that seeps through our soils into our waterways.
We now understand that Roundup is an endocrine disruptor in human cells at levels permitted in drinking water.
And we return to a simple fact, the effect of this ‘lower toxicity status’ conferred by only using corporate studies is the excuse provided by governments to not test for the most common pesticide used on earth.
Independent scientists have been churning out research for years that declares that the current levels that we are exposed to are unsafe. The big 3 agencies simply choose to ignore them or dismiss them.
Without government financing and support, independent scientist’s hands are tied. And it should be about the science. Not denial, not politics, and not corporate protectionism.
When does this become negligence?
 WHO Drinking Water: World Health Organisation/ FAO Pesticide Residues in Food : Part II Toxicological Evaluations 2004 page 95. http://whqlibdoc.who.int/publications/2006/9241665203_eng.pdf
 USA Drinking water: US EPA Reregistration Eligibility Decision Glyphosate 1993. RfD P.19 Drinking water P. 61 http://www.epa.gov/opp00001/chem_search/reg_actions/reregistration/red_PC-417300_1-Sep-93.pdf
The portion of the private Monsanto study the public are permitted to see. WHO document WHO/SDE/WSH/03.04/97 Glyphosate and AMPA in Drinking Water.
Bio/Dynamics Inc. (1981a) A lifetime feeding study of glyphosate (Roundup technical) in rats. Unpublished report prepared by Bio/Dynamics Inc., Division of Biology and Safety Evaluation, East Millstone, NJ. Submitted to WHO by Monsanto Ltd. (Project No. 410/77; BDN-77-416).
Groups of Charles River Sprague-Dawley rats (50 per sex per dose) were fed technical glyphosate in their diets at dose levels of about 0, 3, 10 or 32 mg/kg of body weight per day for 26 months. Survival, appearance, haematology, blood biochemistry, urinalysis and organ weights were not changed. Slight growth retardation during part of the study was noted in the high-dose males. The incidence of interstitial cell tumours in testes showed a statistically significant increase (incidences: 0/50, 3/50, 1/50 and 6/50; historical control range: 3–7%) (Bio/Dynamics Inc., 1981a). This finding, in itself constituting evidence of a carcinogenic effect in rats, should be judged in light of the absence of an effect at much higher dose levels in the more recent 2-year study in rats (see below). This is also valid for the slight growth retardation. The NOAEL was 32 g/kg of body weight per day, the highest dose tested (Bio/Dynamics Inc., 1981a).
 Europe drinking water: S.I. No. 106 of 2007 EUROPEAN COMMUNITIES (DRINKING WATER) REGULATIONS 2007. P.22 http://www.environ.ie/en/Legislation/Environment/Water/FileDownLoad,1541,en.pdf
 Séralini, GE, Clair E, Mesnage R, Gress S, Defarge N, Malatesta M, Hennequin D and de Vendômois JS. Republished study: long-term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize. Research Open Access Springer. Environmental Sciences Europe 2014, 26:14.
 Annex C. ÉTAT QUALITATIf ET QUANTITATIf DES EAUX SOUTERRAINES. http://sigesnpc.brgm.fr/IMG/pdf/tableau_cartes_etats_meso_ap.pdf
 Determination of glyphosate in groundwater samples using an ultrasensitive immunoassay and confirmation by on-line solid-phase extraction followed by liquid chromatography coupled to tandem mass spectrometry. Sanchís J1, Kantiani L, Llorca M, Rubio F, Ginebreda A, Fraile J, Garrido T, Farré M. Anal Bioanal Chem. 2012 Mar;402(7):2335-45. doi: 10.1007/s00216-011-5541-y. Epub 2011 Nov 20.
GM Maizes Threaten EU Water - Another reason to ban glyphosate . http://www.gmfreeze.org/news-releases/176/
 Moms Across America & Sustainable Pulse. Glyphosate Testing Full Report: Findings in American Mothers’ Breast Milk, Urine and Water. April 2014. http://www.momsacrossamerica.com/glyphosate_testing_results
 Friends of the Earth: Determination of Glyphosate residues in human urine samples from 18 European countries. http://www.foeeurope.org/weed-killer-glyphosate-found-human-urine-across-Europe-130613 Study Results: https://www.foeeurope.org/sites/default/files/glyphosate_studyresults_june12.pdf
 Brändli D, Reinacher S; Herbicides found in Human Urine. Ithaka Journal 1/2012: 270–272 (2012) www.ithaka-journal.net Editor: Delinat-Institute for Ecology and Climatefarming, CH-1974 Arbazwww.delinat-institut.org, www.ithaka-journal.net. ISSN 1663-0521