Pesticides in Food - the inadequacies of testing

The authorities would have us believe that no pesticides are permitted for use unless they have been adequately tested.
It is also claimed that no pesticides are permitted for use if they are not safe.

The information given below exposes these claims as suspect in the extreme.


Organochlorines were withdrawn from the market after decades of use because they were found to be persistent in the environment and were linked to endocrine disruption in wildlife.
In their place came the organophosphorus compounds with the claim that despite their known dangers the risk to the environment would be lessened because they were not as persistent as the organochlorines.
These claims were accepted by everyone as factual.

What no one appears to have realised is that pesticides without long-term actions are of little use in agriculture when demands for total insect control need to be met. The pesticide manufacturers must therefore have had the need to find means to prolong the life of the organophosphates in order to improve efficacy of their products.

This effectively nullified the very advantages promoted for OPs but by then no one noticed.

Missed too was the fact that the majority of the safety testing data was produced using the almost pure active ingredient.
All subsequent safety data and exposure calculations were then based on those figures.

The stage was set for major health problems to be triggered in the population as a whole and in occupational exposure situations in particular.

In the 1940s it was becoming apparent that workers were suffering serious adverse health effects from OP pesticides.
An inquiry was instigated and in 1951 Lord Solly Zuckerman issued a report in which the deadly nature of the poisons was recognised.
Lord Zuckerman warned that hospitals should be notified before any OP insecticides were used in the locality and that the words "DEADLY POISON" should be printed on all product labels and cans containing them.
None of his recommendations appear to have ever been implemented and claims were made that the more modern pesticides were much safer. The basis for this claim was that the new chemicals underwent a more rigorous testing regime but still the majority of tests reported involved only the active ingredients

Organophosphates then became more widely used and, with the help of orders from central government, they were also released as veterinary medicines.
In the 1970s compulsory treatment for warblecides was ordered by Government in an attempt to eradicate flies that produced maggots which find their way through the host and finally exit the body of the animal through the skin of the back. The maggots left large holes in the skin and as a result the hides used for leather goods were much reduced in value. The reasons for compulsory use of OP warblecides were given as to aid the leather industry and to improve animal welfare.
Unfortunately little thought was given to the adverse effects on the health of the animals and those who had to handle them. These issues were dismissed as reported in the Black's Veterinary Dictionary which stated that the British Veterinary Association supported the use of OP systemic dressings as early as 1965.
It states " When using organic compounds of phosphorus, such as these insecticides are, one has to bear in mind two potential dangers - that from residues in the carcase to people eating the meat ; and the danger of the cattle being rendered ill by the dose.
However, these compounds have been the subject of extensive trials both in Britain and overseas.

Similar uses were found for OPs in the control of Sheep parasites. Once again the Government stepped in to order farmers to use OPs. This time the compulsory use was to dip sheep in baths of diluted OP but there were also bacterial problems to overcome in the dip bath and so additional chemicals were added, including antibacterials and fungicides. Many forms were supplied to the farmer in separate cans which had to be mixed just before dipping. Once again no one told the farmers that the chemicals were dangerous. Often the only "protective clothing" supplied or recommended was a pair of inadequate gloves.

Farmers were becoming ill. The families of farmers were also affected as they took contaminated clothing back into their homes. On occasion entire families suffered the effects of the toxins but if they were to remain as sheep and cattle farmers they were forced to use the chemicals or face prosecution.

One organic farmer refused to use the OP warblecides on his cattle. Mark Purdey was prosecuted by the Ministry of Agriculture Fisheries and Food.
MAFF tried to force compliance with the compulsory order but the farmer had done his research into the dangers of organophosphates and won his case.
Later he and his many supporters actively promoted the theory that the organophosphates used in warblecides triggered the devastating BSE crisis in the UK.
MAFF again moved against the campaigners but the theory will not die and the official "Infective protein" theory looks increasingly suspect with every new case born after the many and various "feed bans".

All officials of Government quote trustingly from the accepted half-life figures for organophosphates - but are they right?

A Specific Case

A General Farm Worker (GFW) in the UK was exposed to a pesticide liquid diluted for use in grain stores. The mixture was created in June 1991 and he was exposed in January 1992 with pesticide spilled on his hands and legs and the vapours from the liquid inhaled for some days.
He suffered the usual symptoms of OP poisoning and reported the exposure to the UK Health & Safety Executive (HSE) after being told that he would be prosecuted if he failed to do so. That was his second mistake.
The first was to trust his workmates not to do anything to harm his interests or his health.
The other farm staff relied totally on their employer for their incomes and their homes which were "tied" to the jobs. As a result they were prepared to protect their employer when a case of negligence was brought against him. They need not have bothered as it happens because staff at the HSE believed the chemical company claims that the organophosphate active ingredient broke down within days when diluted in water.

The British Medical Association published their guide to "Pesticides, Chemicals and Health in 1990 and the edition of 1992 states " Organo-phosphorus pesticides - A group of pesticides containing a phosphorus atom; they do not normally persist for long but can be very toxic."
Oddly in the same publication (on page 124) they refer to residues of organophosphorus insecticides in barley. These would include residues of pirimiphos methyl added to the grain in stores after harvest. Used for malt the grains would then be soaked in water as part of the brewing process.
Remarkably the BMA states "In other words, beer may provide a surprising, added kick".

The GFW did not believe the claims for short half-life because adverts claimed that applications of the pesticide produced insect control lasting for over a year.
Confused by his own experience and the claims of short active life he wrote directly to the company, then ICI (Imperial Chemical Industries), and asked them how such a liquid should be disposed of after storage.

They wrote "'Actellic D' is not stable when stored as a dilution in water for more than a day or two, as the active ingredient is rapidly broken down in the presence of water. Storage for months is not recommended from an efficacy viewpoint or from a safety perspective. We advise that you consider alternatives to this practice. No additional toxins are likely to be created by this storage method however.
As regards disposal of the material, in the UK, legislation covers all chemical substances, we advise that you contact the waste disposal department of the local authority on the best route to take."

The GFW was not convinced and, no longer having access to grain store pesticides, he decided to test the theory with samples of a garden insecticide called "Sybol" which was made by the same company using the same active ingredient.
The first sample was destroyed by hard frost which burst the container but the following year a second sample was created and, sure enough, six months later the liquid was tested on trapped flies and they died rapidly after exposure.
Concerned that such liquids were reaching the rivers via domestic sewers, farms and waste disposal sites the GFW reported the matter to his MP who was reassured by officials that investigations had found no reasons for concern.
Quote from a Department of the Environment letter to the MP dated July 1993 "The potential pollution impact of household chemicals on freshwater quality was reviewed in 1991 in a report to the Royal Commission on Environmental Pollution. The water research Centre (WRc) considered that no estimate of the quantities of domestic pesticides used and stored in the UK could be made. WRc concluded that if pesticides are used properly in the home and garden, they would be released in only small quantities to sewers...."

The Honourable Nicholas Soames MP in July 1993 wrote in a letter sent to the GFW by his own MP on the same day "If research were to cast doubt on the safety of a pesticide, it could be banned immediately."
Note that little word "could" for it means little without a commitment to act in the best interests of public health.

The GFW's findings were notified to lawyers who reported comments made by Zeneca, the firm then responsible for all ICI agrochemicals.
The barrister stated that "In the meantime Zeneca Limited have now informed those instructing me that they have analyzed the chemicals alleged to have affected Mr ********* and have found that after a period of storage of the length alleged in the present case, the active pesticide content of the solution would have broken down to negligible levels. This information is potentially decisive in our assessment of the merits of this claim."

In the meantime the case was reviewed by the HSE's Pesticide Incidents Appraisal Panel (PIAP) on two occasions and again the false half-life data was relied upon as a means to support the refusal to recognise that the GFW had suffered the effects of the poison.
Quote " Actellic D would have been present in the drainage system at concentrations too low to cause illness, if indeed it was present at all.
On this basis the Panel concluded that there had not been an incident giving rise to significant pesticide exposure and for this reason your case will be classified as "not confirmed" for the purposes outlined above.

At that time the term "Not confirmed" was an even weaker appraisal of the connection with the chemical than was the term "Unlikely".

In the UK there are provisions which provide income for those injured at work and no longer fit for work. For those poisoned by organophosphorus insecticides those provisions fall under the Industrial Injuries Compensation Acts, Prescribed Diseases, C3 Causative Agent 4["c" is for chemicals, 3 for organophosphates, and the causative agent 4 is OP pesticides]
The GFW claimed the benefit but it was denied to him on the grounds that there was, quote "no evidence of direct contact with pirimiphos methyl, exposure identified only by smell....."

This benefit is controlled by the Department of Works and Pensions. The Health and Safety Executive, and therefore the Pesticide Incidents Appraisal Panel, are also part of that government department.

By now the GFW had obtained samples of diluted Actellic D taken from liquid prepared for treating the structures of grain stores but he waited for the right time before telling anyone. After six months had passed he tested the liquid, again using exposed flies, and again the flies all died rapidly after exposure.
He reported his concerns to Zeneca, the manufacturers of the chemical.
They wrote, quote " Relatively brief contact with water, as the spray dillutant, followed by exposure to atmospheric moisture results in the desired level of persistence of 'Actellic'. This must be distinguished from prolonged contact with water in a spray tank, or in damp soil, during which time there will be a substantial loss of the active ingredient by hydrolysis and a corresponding reduction in its insecticidal activity......We stand by our estimate of 3 1/2 days as the time for degradation in soil by microbial activity under UK conditions. I repeat that that [sic] the degradation process and products have been thoroughly investigated and the degradation products are less toxic than pirimiphos-methyl.....we do know that it degrades in water."

The Labour Government came to power in the UK in May 1997 and, since they had made promises to help those exposed to organophosphates before the election, the GFW wrote to the new Minister for Agriculture, The Right Honourable Jack Cunningham MP imploring him to act quickly as harvest approached and the poison, about which there were serious safety concerns, would again be added to the grain. If this was allowed to happen then children would still be eating the poison in the next century.(European Rules stated that grain sold into what they called "Intervention" stores must be protected from infestation for 5 years).
Zeneca themselves warned against ingesting the chemical and yet treated grain can be eaten without any withholding period after treatment.

The Pesticide Safety Directorate replied for the Minister.
Quote "Finally, I would assure you that the government would not hesitate to act to revoke or restrict any pesticide approval if there were clear evidence that it posed an unacceptable risk to users, consumers or the environment.
Note - the key word there is "unacceptable". There is an apparent willingness to sacrifice vulnerable individuals to support policy.

The GFW reported his detailed concerns to the Minister but again the Pesticide Safety Directorate was given the task of providing the reply.
They wrote "Our definition is that the half life of a chemical is the time taken for half of the applied amount to degrade or dissipate. the applied dose will therefore determine the duration of effectiveness, which may be greater than the half life. Specifically, pirimiphos-methyl is degraded in soil, usually with a half life of between 3 and 25 days. In sterile water at pH 6.5 pirimiphos-methyl is hydrolysed with a half life of less than 4.2 days, but when exposed to light, the reported half life for aqueous photolysis is less than 1 day. The time taken for degradation or dissipation in grain stores is likely to be greater than that reported for soil or water. this is because grain stores are usually maintained at a much lower moisture content than that required for significant hydrolysis or microbial degradation of the pesticide. In fact, the main route of dissipation of pirimiphos-methyl from grain stores is likely to be volatisation.....I can confirm that exports of grain treated with pirimiphos-methyl are permitted.....the Codex Alimentarius Commission has established a standard of 10mg/kg for cereal grains which would be used as at least indicative residue level purposes by many countries."

What is interesting is that in internal documents released to the GFW under the UK Data Protection Act the PSD's Pesticide Residue Section had written "(an approval would be sought for the diluted version if this was intended to be stored) I therefore suspect that Zeneca do not hold data to show that the diluted version is stable (as we would not ask for it).....

......"I would expect that the pirimiphos-methyl in the tank would have hydrolysed (as the Actellic D had been diluted with water).....

....."As I feel that the pirimiphos methyl would have hydrolysed I wonder if the hydrolysis products are active against insects. It seems to me that a toxicologist should consider whether the hydrolysis products (e.g. aminohydroxypyrimidines from the pyrimidine part of the molecule and products from the phosphorothioate part of the molecule) have any effects on mammals (and insects).....

.....(i assume that the non-active ingredients of Actellic D are not of concern)"

These are remarkable statements given that at this time the chemical was under review by this body in order to form the first evaluation for its safety since its introduction as an additive to food grains in the mid 1970s.

The GFW wrote to the Pesticide Safety Directorate reiterating his concerns and notifying them of the results of his experiments. He raised concerns that the testing reported involved sterile water of fixed pH and not the variety of tap water used in spraying operations, which would include additives such as chlorine and fluoride that might influence the chemistry of any diluted pesticide. He wrote that in fact the PSD letters supported his own arguments against Zeneca but to no avail.

In the United States of America the Environmental Working Group in Washington DC published a book called "Overexposed - Organophosphate Insecticides in Children's Food" and they called for an immediate ban on pirimiphos methyl and other OPs.
Quote "at least five high risk OPs, methyl parathion, dimethoate, chlorpyrifos, pirimiphos methyl and azinphos methyl, must be banned immediately for all agricultural use."

UK regulators were notified of this publication but their response was simply to confirm that they had copies and that they regarded it as "a challenging document but the "challenge" it seems was how to argue against it for no action was taken on its recommendations.

In the same year, 1997, the famous Hill v Tompkins case went to trial and the result was the legal recognition that the chemical had harmed the plaintiff.
Evidence given on oath during the trial questioned the safety data of the chemical and the reliability of the methods used to test its safety.

Despite all this, and having copies of the labels from the product packaging warning against contaminating food with the chemical, the PSD produced their evaluation document for pirimiphos methyl with all the old claims for short half-life included in its accepted data. Its Approval was upheld.

For example [Page 38] states that Pirimiphos methyl degrades in sterile water to half life in 3.2 - 4.2 days in darkness and less than 1 day with exposure to sunlight which means that the effects of acid or base on the active ingredient are unknown.
[Page 39] admits that in some experiments sorption of pirimiphos methyl into PVC containers may have occurred and that monitoring for the chemical in water is not extensive.

[Page 40] The chemical is of moderately high lipophilicity and has a moderate rate of degradation......
[Page 41] Residues in food. Tests were performed using 98% PURE Pirimiphos Methyl and analysis of fat showed that 55% of residues remained as pirimiphos methyl and indicated little breakdown of phosphorothioates.

[Page 62] In processing studies done in 1973 residues were determined in bread, flour, and milled products using treated grain.
White bread was found to contain about 10% of the applied product and about 40% remains in wholemeal.
There is an apparent increase in this transfer with storage.
It rises to 15% in white bread and 43% in wholemeal bread after 3 months storage.

[Page 70 - 77] Lists Maximum Residue Levels (MRLs) in food where such standards are applied.
Interestingly the highest levels permitted are found in PEANUTS
Permitted levels are set at 15 mg kg for crude peanut oil, 10 mg/kg for edible peanut oil and 25 mg/kg for whole peanuts.
[page 76] Next highest are Cereals at 10 mg/kg , Rye, Olives, Lettuce, Spinach, and cultivated Mushrooms at 5 mg/kg.
Could this explain "allergies"?

Post-harvest residue data trials showed that "levels declined slowly if at all".

Incredibly the approvals for this food additive continue despite the recorded fact that in the Ames Test using salmonella typhimuium and E.coli.
Pirimiphos methyl induced mutagenic activity in Salmonella typhimurium strain TA100 in tests done by several researchers.

Most of the toxicological studies were of short duration, in subjects not regularly exposed and were of short duration.
In the real world exposures are almost continuous and are for a life time, including during development in the womb.

With the PSD ignoring all the data gaps and their own recorded adverse reactions the GFW sent copies of his evidence to the Prime Minister but it was all ignored. He found similar problems with the data on the organophosphate herbicide "Roundup" and his information was again ignored.

In 1998 David Ray of the UK Medical Research Centre - the same body which gave evidence of the harmful effects of OPs to the 1951 Zuckerman report - produced a publication called "Organophosphorus esters: An evaluation of chronic neurotoxic effects"
On OP pesticides he wrote, on page 4, "their efficacy, low environmental persistence and low production costs will probably ensure their continuing use well into the future as an important component of integrated systems for pest control".

The Official Group on OPs Report to Ministers stated on page 29 that ""We noted David Ray's view that such exposures are not likely to be responsible for any subjectively apparent adverse health effects;
the review notes that individuals vary in their sensitivity to OPs but does not characterise, or discuss in detail, the distribution in the population.
the review also raises the possibility that there may be a mechanism causing long-term effects from long-term low-level exposure, but Dr Ray concludes the mechanism is not currently understood...."

In November 1998 the UK joint working party of the Royal Colleges of Physicians and Psychiatrists published their paper "Organophosphate sheep dip. Clinical Aspects of Long-term Low-dose Exposure" and wrote "Because of the bio-persistence of the organochlorine insecticides, from the 1980s onwards the use of OP insecticides in most countries tended to increase, as they supplanted the organochlorines".

In 1999 the UK Department of Health's Committee on Toxicity was given the task to determine if long-lasting adverse health effects could result from repeated exposures to OPs. Their conclusions are highly questionable and in their report they declared that "4.3 In theory OPs could enter drinking water via industrial effluent, seepage from toxic waste sites, from the washing of fleeces of treated sheep, and from run-off water after agricultural use. In the UK, run-off water from agricultural use is likely to be the most important route by which water supplies are contaminated. Exposure to OPs via drinking water is limited by their hydrolysis and degradation through the effects of light and pH (acidity and alkalinity), and through metabolism by micro-organisms.
Data collected between 1993 and 1996 show that 5 to 10% of fresh water samples and 1 to 3% of ground water samples in England and Wales contained detectable concentrations of diazinon and propetamphos. Higher concentrations (>100 ng/l) were present in 2 to 3% and 0 to 1% of fresh water and ground water samples respectively.
Recent results from a monitoring programme by the Environment Agency, Wales, indicated that the presence of diazinon in river water was widespread, detectable amounts being found in 75% of the 107 river sites monitored.4 In 29 cases, levels were above the maximum allowable concentration in the Environmental Quality Standard (100 ng/l). Ingestion of two litres of water containing 100 ng/l by an adult would give an oral intake of about 3 ng/kg per day which is less than 0.2% of the ADI for diazinon and less than 4% of the ADI for propetamphos.
4.4 No data are available on the extent of exposure arising from household uses of OPs or from secondary exposure to occupational sources (e.g. in farming families) in the UK.

"No data" - after decades of regular and widespread use, even as undeclared and systemic food additives, and residues excreted in milk drunk directly from cows by farming families....

Further they claim that "4.38 OPs persist in the fleece for a time after dipping, with a half-life for loss from the fleece of 12 to 53 days, depending on the nature of the OP and site of measurement. The potential for exposure of workers from handling sheep in the weeks following dipping would be limited, compared with that during dipping, because of the small surface area of skin exposed (primarily the hands) and the vehicle ( wool grease which would not wet large areas of the skin and would not enhance absorption)

Meanwhile the years passed and the diluted samples still killed insects. The information was reported by the GFW to the media and to scientists specialising in the field but there was no support.
Some scientists claimed that the explanation for the continuing toxicity was due to the presence of solvents.
Some claimed that the active ingredient broke down to form the more deadly TEPP and Sulfotep organophosphates.
Some even stated that those deadly OPs were permitted contaminants and that this would explain the ongoing toxicity.

Some individuals, claiming to be "scientists", even claimed to be able to drink the diluted chemicals without harm if they had been stored for six months - but they soon changed their tunes when asked to drink samples in front of cameras.

One scientist, acting for the defence in the GFW's civil case, even claimed that pirimiphos methyl was not volatile, and would therefore not be harmful by inhalation.
He also relied on the accepted half-life figures but did at least admit that the GFW had been exposed to an illegal mixture of two organophosphates - without actually realising that such mixtures are unlawful, or that his own statement proved that the label instructions had not been followed by the employer's staff.

Some years after the GFW's case collapsed due to those false statements he managed to find, completely by chance, the address of a company prepared to test his samples.
Without saying how long the liquid had been stored he simply asked for the presence of pirimiphos methyl to be determined. The company had already confirmed that the test procedure could not determine any breakdown products or solvents and, because the testing would not be done for ten days after receipt of the sample, the results were not expected to be positive.

To everyone's total surprise that was not the case.

The sample was taken from liquid declared to have been formed by the mixture of 12mls of Actellic D (250g/l pirimiphos methyl) per 1000mls of water.
This initial mixture dilution rate is one of about 3,000,000 micrograms of pirimiphos methyl per litre of water (3g/l).
Over 5 YEARS after dilution the samples were certified to contain 6,280,000 micrograms of pirimiphos methyl per litre (6g/l)

Almost in disbelief the GFW requested reassurance of test reliability and it was then confirmed that the testing was 99% accurate and that the methodology, employing the scientifically recognised technique of mass spectrometry, was entirely acceptable for, and supportable in, a court of law.

The results appear below.

The Sample was mixed on 25th June 1999

The testing was begun on the 2nd July 2004

pirimiphos methyl increases in concentration with time

Names and addresses have been removed at this time only to protect those involved.

pirimiphos methyl does not break down in water when in the Actellic D formulation

It is now clear that all those who quoted the manufacturer figures for half-life of "about 4 days" in water had never actually tested the chemical to ensure accuracy of the data.
They simply accepted as read the published figures - even though the chemical was harming people.
They did not seem to realise the dangers of accepting the half-life figures for the active ingredient as representative of those for the protected OPs in the commercial formulations.

What should be of great concern to us all is that if the co-formulants in this one commercial product prevent the breakdown of the Organophosphate then it is highly likely that the same is true for all other commercial pesticide formulations and veterinary medicines.

The GFW passed the information to "campaigning" members of the UK Parliament.
The reply?
"I saw Lord Whitty last evening and mentioned that I would like to see him and his scientists soon. As we break up for the summer recess next week it is likely to be either September, when we are back for a fortnight, or October. Time to make a good case, I hope."

How much time do they need? Will they ever tell the truth?

Another harvest treated with deadly poisons. Another 5 years with children eating treated food.

An urgent investigation into the entire matter is required.

If a simple, disabled ex-farm worker is able to discover the truth for a few pounds why have so many highly paid scientific researchers, Governments, Regulators, lawyers and doctors,
failed us all so badly?

Questions were asked of the Minister but there was a long delay in obtaining the answers.
To see the questions, answers and comments on the information given click here

Dated 10/7/2004 Updated 29/4/2005

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