Official comments on pesticides added to food

How safe is a "safe" pesticide when added to food?

How Government officials avoid telling the truth about the pesticides in our food

DEFRA were asked questions - in Italics.
Their answers and comments on those answers are seen below.

February 2005


When we met on 29 November you gave me a note containing a series of questions about pirimiphos methyl. As promised, officials at the Pesticides Safety Directorate have looked at these, and the following responses are based on the information they have supplied me with. I apologise for the excessive length of time this has taken. For ease of reference I have reproduced each question in italics below, followed by its response.

1. The first safety Evaluation for Pirimiphos Methyl was published by the Pesticide Safety Directorate after the Hill v Tomkins court case in 1997 and recognised gaps in the safety data which were required to be filled. Has that research been done?

A review of pirimiphos-methyl, encompassing both human health and environmental assessments, commenced in 1994 as part of the UK routine review programme of older pesticides. The review was considered by the Advisory Committee on Pesticides in 1997 when it recommended that approvals should continue subject to the imposition of additional operator and environmental protection requirements, and the provision of further data in relation to all areas of the risk assessment. The conditions of approval were amended and data requested in 1998 with data submission deadlines of between one and seven years for provision of the data.

Pirimiphos-methyl has also been reviewed as part of the UK review of anticholinesterase compounds which was announced in 1998. As a result of this review, Ministers agreed that further data were necessary and a Data Call In Notice requesting data was issued in March 2001.

The UK was assigned as the Rapporteur Member State for the EC review of pirimiphos-methyl which began in 2002. The UK evaluated the dossier supplied by the notifier and this included data supplied to and generated as a result of the two UK reviews. The EC review is still ongoing and a decision has yet to be taken regarding inclusion in Annex I of Council Directive 91/414/EEC. All the necessary steps have been taken, therefore, to fill the 'data gaps' that were identified in 1997.

Comment : It is interesting that the review of pirimiphos methyl started in 1994 when a letter written in 1992 stated that the National Poisons Unit in London was already concerned about the chemical and was actively seeking patients who had been exposed even then.
It is good to see that they admit that the Evaluation Document was published in 1997 - the Food Standards Agency stated that the date was wrong and that the chemical was reviewed in 2001.
The Evaluation documents are available on line at
In any case the Evaluation Document in 1997 admitted on several occasions that it was not possible to extrapolate from data on old formulations to those currently marketed - in other words the majority of the testing, as scientists have explained was completely worthless.....
Additional operator protection was required but why? - if it is "safe"?
They couldn't have done a very good job on the review either because the dust form was withdrawn due to lack of safety data in 2003 - and that didn't contain the dangerous solvents that are in the form still approved for use.
While they keep calling for "new data" we are all eating the poison.
That cannot be right and should not be an acceptable approach to food dafety.

2. The Pesticide Safety Directorate were aware that the half-life figures for the commercial formulations of pirimiphos methyl could be grossly understated before the Evaluation Document was published in October 1997. Has the Pesticide Safety Directorate performed tests to confirm the quoted figures?

The Pesticide Safety Directorate (PSD) is not aware of any concerns regarding the half-life of pirimiphos methyl that would impact on its safety or efficacy, although this is of course subject to the results of the current EC review.

The UK's regulatory requirement is that all approved pesticide products containing pirimiphos methyl must be stable in formulation and in solutions prepared for use, but that they should then break down in the environment following use. It is for the Approval Holder to generate any data required to confirm that this standard is met. PSD does not generate its own studies to support pesticide approvals.

Comment : What a lot of nonsense. Concerns about the persistence of Actellic D - the liquid form - have been raised since well before 1997.
The PSD knew all about it.
All they do is claim that because they consider it has no effect on their safety calculations then they don't have to do anything.
The problem is that they DO know that this is a safety issue.
If the exposure and MRL calculations assume short half-life then all exposures after a few days are assumed to be of nil effect.
The problem is that the chemical is active for as many years as they claim days and we now know that its concentration increases - probably due to the evaporation of the water-based carrier.
Even the Evaluation Document admitted that residue levels actually RISE in treated grain during storage.

A UK grain farmer's story demonstrates the real risks from this prolonged active life as he has been hospitalised numerous times following entry to a previously treated building and exposure to treated areas which should theoretically have been "safe" long ago.
Others had a similar experience when a film crew filmed for a documentary and the residue in a hand held sprayer's tank contaminated a house five years or more after it was last used -and it had been thoroughly washed after last use and twice before the film crew arrived.
An empty and washed plastic bag, which had once held the dust form, was sent to the PSD some years ago with a warning about the fumes given off by it. That bag had been washed with a hosepipe, but then washed again in warm soapy water. It still gave off fumes and so was then thoroughly rinsed, again using a hosepipe and then hung outside overnight to dry - but it rained!
Next morning when it had dried it was placed in a plastic bag, inside another plastic bag, and then in a "jiffy bag" and was posted to another exposed individual because they wanted the instructions printed on the bag.
The recipient, who was wearing a respirator because the parcel had already affected his health, telephoned the sender the next day.
He knew what was in the parcel before the postman could give it to him as he could smell the chemical.
His health was obviously affected.

That is why the extended half-life is dangerous to health.

3. Pirimiphos methyl is approved for use as an insecticide incorporated into grain, which is to be used for human consumption. Are there any plans to ensure that this food additive is declared on food labels?

Pesticides are only approved if data supporting their safety and efficacy are submitted, including data demonstrating that there will be no concern from residues in food, where these are below the Maximum Residue Level. Given that these safeguards exist, there are no plans to declare the presence of pirimiphos methyl, or any other pesticide, on food labels. Pesticide treatments are not classed as food additives.

Comment : The Food Standards Agency also claim that pirimiphos methyl is not a food additive but is a pesticide. In reality it is both and they cannot lawfully deny that fact.
The Food Standards Agency have been referred to the following quotes from the legislation - as yet there has been no reply.

Statutory Instrument 1995 No. 3187
The Miscellaneous Food Additives Regulations 1995

"food" means food sold, or intended for sale, for human consumption and in regulation 6 and for the purposes of regulation 9 includes a food additive; "food additive" means-

(a) any substance not normally consumed as a food in itself and not normally used as a characteristic ingredient of food, whether or not it has nutritive value, the intentional addition of which to food for a technological purpose in the manufacture, processing, preparation, treatment, packaging, transport or storage of such food results, or may reasonably be expected to result, in it or its by-products becoming directly or indirectly a component of such foods; or
(b) a carrier or carrier solvent;

Food Safety Act 1990 (c. 16)
Meaning of "food" and other basic expressions. 1.-(1) In this Act "food" includes-
(a) drink;
(b) articles and substances of no nutritional value which are used for human consumption;
(c) chewing gum and other products of a like nature and use; and
(d) articles and substances used as ingredients in the preparation of food or anything falling within this subsection.


"contact material" means any article or substance which is intended to come into contact with food;


"food source" means any growing crop or live animal, bird or fish from which food is intended to be derived (whether by harvesting, slaughtering, milking, collecting eggs or otherwise);


(4) The reference in subsection (3) above to preparing for sale shall be construed, in relation to any contact material, as a reference to manufacturing or producing for the purpose of sale.
Presumptions that food intended for human consumption.


The above implies that pesticides added to grain in storage are indeed technically food additives and that they should be declared as present on the food labels.

The UK regulators may be "happy" but the scientists in America who called for an immediate ban on these chemicals in 1997 certainly were not and showed real concern. For details about those concerns see the Environmental Working Group publication
"Overexposed - Organophosphate Insecticides in Children's Food"

4. Ministers have repeatedly stated that pesticides will be withdrawn from sale if there is any indication of risk to human health. Pirimiphos methyl is the only pesticide that has been proven in a United Kingdom court to cause long-term harm to human health. Are there any plans to ban the use of this pesticide?

When you talk about proof of harm, I assume you are referring to the Hill v Tomkins case mentioned in your first question. I note that the case arose from the inappropriate handling of the pesticide on the farm concerned.

Pesticides are inherently hazardous substances, and if they are improperly handled or used they may cause harm. The role of the regulatory system is to introduce general and specific controls to minimise the risk of such situations occurring. If PSD obtained findings that indicated that approved pesticides containing pirimiphos methyl were being used in accordance with these controls but still resulted in harmful exposure, then action would be taken to amend or revoke the approvals granted.

Comment : Just because the Hill case involved the abuse of the chemical does not mean that they can now imply that the chemical is "safe".
The effects of the chemical are recognised - and they were reported under oath in court by internationally recognised experts.
The answer admits that pesticides are hazardous substances so why are they permitted to be added in an uncontrolled manner to our food?
Just because only one farmer has been proven in law to have abused the chemical does not mean that others have not. Many cases have been reported including one where a farmer treated stored grain with Actellic D using a leaking knapsack sprayer - an application method now banned because of the risk of overdose.
The farmer would not have been able to make the legally required declaration of use because the methods used are not approved.
MPs and voters are frequently told that if there was any doubt over the safety of a pesticide then it would be withdrawn.
The answer given is not good enough and does not properly address the serious issues involved.

5. The regulatory bodies repeatedly state that no chemical is permitted for commercial use as an agricultural pesticide if it has been shown to cause peripheral neuropathy. Both pirimiphos methyl and chlorpyrifos have reportedly caused this neuropathy. Are there any plans to ban these chemicals?

Negative results have been seen in the regulatory delayed neuropathy studies concerning pirimiphos methyl and chlorpyrifos. At doses in the lethal range, there are published reports that chlorpyrifos can produce delayed neuropathy; such reports were considered in the UK review of chlorpyrifos and the overall weight of evidence was that chlorpyrifos did not present a risk of induced delayed neuropathy. No evidence of delayed neuropathy has been identified in the various reviews of pirimiphos methyl.

Comment : The Government should be aware of the doubts surrounding the testing of those chemicals.
Those doubts were raised during the Hill case when cases of peripheral neuropathy, including that of Mr Hill, were drawn to the attention of the court.
Chlorpyrifos has been implicated in peripheral neuropathy - and there are numerous references to that in the public domain.
The means used for the testing of pirimiphos methyl for peripheral neuropathy was criticised in open court during the Hill trial.
In any event the testing is likely to have involved almost pure active ingredient (it is not declared) and not the commercial formulations which contain co-formulants that may also be nerve toxins.
It is reported that during the testing process the birds RECEIVED PROPHYLACTIC DOSES of 50 mg/kg P2 S and 10 mg/kg ATROPINE SULPHATE PRIOR TO DOSING AND 3, 5 and 21 HOURS AFTER DOSING which kept them alive but must also have reduced the risk of developing peripheral neuropathy.
Regular users of the commercial product do not have that advantage and nor do the consumers who do not have an end to their exposure experiment in sight as yet - and are not given access to the protective treatments or antidotes.

Officials claim that no pesticide is permitted for use if it has the potential to cause peripheral neuropathy.

That is obviously not true.

6. A variety of chemicals are approved for admixture to food grains. It is admitted that little or nothing is known in regard to the potential toxicity created when grain treated with different chemicals is mixed and processed. Has any research been commissioned into the reactions between these chemicals?

A working group of the Committee on Toxicity published a report in September 2002 on the risk assessment of pesticide mixtures. This can be found on The working group concluded that dose additive effects would only be seen with compounds having the same toxic action. Further work and research is being performed to investigate exposures to chemicals with the same mechanism of toxic action. When the United States' Environment Protection Agency performed a combined assessment for all organophosphates the conclusion was that exposures were acceptable if dichlorvos was excluded (dichlorvos is no longer approved in the UK).

Comment : The claims made in this answer cannot be true.
An exposed worker was in contact with the manufacturers and government agencies when he discovered that he was exposed to an illegal mixture of two anticholinesterase OP grain store insecticides and their solvents.
NONE of the official bodies and chemical companies contacted could say how dangerous that mixture was.
One scientist researching mixtures suggested that the toxicity would have greatly increased, especially when the solvent in one of the formulations reacted with the OP in the other.
While we await further work we are eating these chemicals in combination with other true "residues" of pesticides such as glyphosate in the food we eat.

Grain store pesticides are not residues - they are deliberate additions to our food.

Those answering the questions do not know but they are making dangerous assumptions.

7. Contrary to repeated claims by the regulatory bodies scientists demonstrate that glyphosate products inhibit cholinesterase and induce a potentially dangerous synergistic reaction in the presence of other organophosphorus pesticides. Are there any plans to restrict the use of glyphosate on food crops?

Although glyphosate is sometimes classed as an organophosphorus compound, it has a different mode of action and does not inhibit cholinesterase activity unlike typical organophosphorus compounds. It is not therefore capable of producing the same harmful effects as other organophosphorus compounds. PSD is not aware of any evidence that glyphosate produces any significant inhibition of actylcholinesterase in vivo, but would certainly consider any new evidence submitted.

Comment : The question was not simply about glyphosate but products containing glyphosate.
The two cannot be separated. Demerdash et al did show cholinesterase inhibition from glyphosate alone and test results of a woman in the USA showed her cholinesterase levels dropped dangerously after exposure to Roundup Pro many years ago.
Recently research showed that glyphosate is also proven to be an endocrine disruptor but the regulators only measure risk by cholinesterase inhibition it seems - and get that wrong.

8. Due to the extended half-lives of organophosphates in water reports suggest that rain and river water are now being contaminated with these chemicals. What plans are in operation to protect the water supply and the environment?

It is true that commercial formulations of Organophosphate (OP) pesticides often contain a component which specifically protects the OP active substance from breakdown processes during storage and in the spray mixture, so as to extend the active life of the OP. However this extended half-life does not continue on into the period when the pesticide is applied to the open environment. Any mixture of chemical components such as a pesticide formulation, once applied to the open environment, become separate entities and each individual chemical behaves as if it were alone in the environment. Thus the OP active substance is no longer protected from breakdown processes once it is in the open environment, such as the soil or natural waters that it may encounter following application.

OP pesticides dissipate from soil and natural waters such as rain and rivers via a number of different routes, following their field application under conditions of normal agricultural use. The principal routes of dissipation from soil and water are biological degradation and hydrolytic degradation. The organophosphate part of the pesticide molecule is easily broken down in the environment, usually by the action of soil micro-organisms such as bacteria (biological degradation) or by chemical hydrolysis in the presence of normal environmental components (hydrolytic degradation).

Thus these organophosphate compounds are not persistent in the rain or river water -having short to moderate half lives, and they are broken down following normal agricultural application to smaller harmless inactive degradates, not containing the organophosphate part of the molecule, which are then subject to slow natural incorporation into normal natural constituents. PSD has not identified any potential for contamination of natural waters such as rain or rivers by such OP pesticides following their normal use. As such, the water supply and the natural environment remain protected from OP pesticides.

Comment : This is an admission that we have been waiting to see in print for many years.....

They do use a chemical to protect the OP active ingredient.

Why have they denied it for so long?
Could it be because they want us all to believe that Organophosphates are more environmentally friendly than the persistent organochlorines - the only reason why they accepted the greater risk to man from the OPs?
As seen above that persistence remains long after the chemicals are released into the environment.
In 1997 it was reported that freshly prepared grain baits could kill 3.3 crickets per grain but grain baits that had been weathered for 3 weeks, including exposure to rain still killed 1.4 crickets per grain.
That is very effective for a chemical with a claimed half-life of days in water and hours in sunlight....

If OPs are easily broken down why did the Danes find Roundup in their water supply?
Why did the Actellic D sample DOUBLE in concentration after more than 5 years diluted in water?
Why do we get lied to at every turn with the use of untested theory?
Is the Pesticide Safety Directorate the authority for detecting OPs in water?
The laboratory used to test the diluted pirimiphos methyl actually tests for residues in water for the water companies - and the PSD dismissed their findings!

9. It is clear that part of the commercial formulations of organophosphorus pesticides serve to protect the active ingredient from the breakdown process so as to increase the efficacy and extend the effective active period of the chemicals. Has any research been commissioned as to the potential of those protectants to prolong the effects of the chemical within the body?

Most pesticide formulations (including any added protectants) will be tested for acute oral toxicity in rats. If the results of these studies indicate an increased toxicity relative to that expected based on the properties of the components, additional investigations will be performed.

PSD's understanding is that the protectants in pirimiphos methyl products are likely to prevent, rather than increase, the formation of more toxic compounds in the can.

Comment : If the full formulation is tested at all stages then why do the vast majority of results relied upon in the 1997 Evaluation Document involve almost pure active ingredient?
If water is involved it is also pure and pH is controlled.
It is not the real world.
The admission that chemicals protect the OP tend to explain the findings of the 5 year storage period in water with no breakdown. That would have had a significant effect in a UK High Court organophosphorus case when such chemical presence was denied at all stages.
How do they explain the detachment of this chemical from the OP since it remains bonded in water for so long - contrary to claims made in writing by the PSD, ACP, HSE, ICI and Zeneca.
How could non-scientists be be right and all these influential organisations be so wrong for all this time?

10. The safety factors for pirimiphos methyl are determined on No Observable Adverse Effect Levels in animal experiments and measurable cholinesterase inhibition. What effects are known to take place in the body at exposures below those levels? Are those effects reversible or irreversible when exposed to these cumulative poisons?

It is internationally accepted that a 20% inhibition of acetylcholinesterase activity is not associated with adverse clinical signs. The data required to support approval of a pesticide include repeated dosing every day for up to two years; therefore any cumulative effects would be detected and taken into account in the risk assessment.

Comment : They have avoided the issue raised.
They were not asked about cholinesterase inhibition.
It is however interesting that they write about 20% inhibition not being associated with clinical signs since according to figures released to one poisoned patient his plasma cholinesterase levels rose from 5.9 to 8.2 KU/L between July and September 1992, that was between 7 and 9 months post exposure - if we can trust their testing or their reports.
Doctors later denied that he had been poisoned.

The interest and the reason for the question was in respect to all those other actions of OPs mentioned by COT, which they claimed not to understand but admitted to result in the same endpoints....
The cumulative effects of endocrine poisons and those that interfere with vital metabolic processes and DNA do not appear to be properly considered.

11. The dust form of pirimiphos methyl and crop treatments were withdrawn through lack of supporting safety data. Why did the approval for use as an undeclared food additive continue?

These products continue to be marketed and used because there is sufficient data to support their approval. As stated above these pesticide treatments are not food additives.

Comment : We have to wonder if these people actually know how grain store chemicals are used?
Are they assuming that they are only used on the structure of the stores?
It certainly seems that way from the Food Standards Agency correspondence in which concern was expressed regarding "contact with food" rather than incorporation into food.
If a bag that has contained treated grain is too dangerous to then be used to store food then how can it be claimed by the same people to be safe to eat the treated grain that made the bags too toxic in the first place?

Are the "data gaps" forgotten or considered to be unimportant?
As for "not a food additive" Question 3 applies!!

12. We are expected to be reassured by the residue testing programme. How many tonnes of wheat are treated with insecticide admixture annually? How many grammes of bread, flour, cakes, breakfast cereals and biscuits are tested annually? Are abnormally high results investigated or are they discounted in the calculated averages for those residues found?

The most recent survey for wheat grown in Great Britain during 2002 and stored in 2002 to 2003 indicates that 1,242,491 tonnes of home produced wheat were treated with insecticide admixture, which is 7% of stored grain.

A number of staple foods are examined every year as a part of the UK surveillance programme, including bread. Cakes, biscuits and breakfast cereals are sampled as part of the "rolling programme" of pesticide testing and are examined every 4- 5 years. Biscuits were last examined in 2003 and breakfast cereals were last examined in 2001. Cakes were looked at in 1998. Cereal grains are also examined regularly where samples are taken direct from grain stores in the UK.

A total of 216 samples of bread with a total weight of 216kg were tested in 2003. 72 samples of flour with a total weight of 72kg were tested in 2002. 48 samples of cakes with a total weight of 24kg were tested in 1998. For breakfast cereals 96 samples with a total weight of 96kg were tested in 2001. 96 samples of biscuits with a total weight of 48kg were tested in 2003. No adverse residues were found and all occurrences of pirimiphos methyl were within accepted maximum residue levels.

If higher than permitted residues are found in monitoring samples, risk assessments are conducted based on the highest residue found and the most vulnerable consumer (based on body weight and consumption patterns). It is standard practice to follow up higher than expected residues or unusual residues with the supplier. However, as noted above none have been found for these commodities.

Comment : Are we to believe that they tested every 1 kg loaf in its entirety in their 216 or did they take a sample from each loaf?
Either way it is almost no testing at all given the 1.24 million tonnes of the "declared as treated" grain.....?
Calculations indicate that only 0.0000367% of treated grain is tested - and then only if they test the entire loaf and every crumb of their samples of biscuits, cakes and cereals.
It is suspected that they test just a small sample of each loaf, biscuit, and cake!
Is it surprising that they didn't find the illegal or excessive use of pesticides - or Sudan 1?
We had to wait for Italy to find that for us!!!
Nor did they ever find the massive over-doses reported when whole bags were dropped into grain stores or, as has happened, when a mechanical applicator releases enough to treat 50 tonnes of grain into one trailer load after cleaning or adjustments.....

13. Residue testing appears to examine for active ingredients only. The toxicity of many breakdown compounds are admitted to be unknown and the effects of mixing chemicals are also unknown, especially for stored products. Can the Minister explain how we can be confident in a testing procedure when the substances to be tested are unknown and of unknown toxicity?

The toxicity of breakdown products is considered as part of the authorisation process. Animal and plant metabolism studies have to be conducted to identify breakdown products and further toxicity tests of key metabolites may be required. Key metabolites will then become part of the agreed "residues definition" (along with the parent compound). Such metabolites may then be included within the surveillance programme.

The Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment has considered the possible cumulative effects of pesticide residues in food, referred to as 'the cocktail effect'. It concluded that, at the very low levels at which residues occur, it is unlikely that there will be significant interactions between residues and there is no evidence that consumers are being harmed. However, the Committee recognise that mixtures of residues could theoretically present a higher risk than single residues and made recommendations for further action. Together with the Foods Standards Agency and other regulatory agencies, work is already in hand to take forward these recommendations.

Comment : How can they consider all the breakdown products if they are not known?
Internal documents from the Pesticide Residues Section of PSD state that they have no idea if the breakdown products are toxic to insects or mammals - and that is ignoring the co-formulants too.....
All these fine words are designed to impress but they are based on false assumptions and opinions which often come from people with no practical experience at all.

COT is a government agency and could not even find the data used to form the Act of Parliament that admitted the cumulative dangers of OPs in 1958.
They also admitted to not understanding the science of those "other actions" so deliberately avoided in the answers to these questions.
The COT might be the best we have but they aren't very good it seems....
The Food Standards Agency is directly linked to COT, the DoH and Defra so we cannot assume that they are not influenced by those false assumptions and opinions.

If those of us who have been poisoned were experimental animals the scientists watching us would be recording our symptoms as Observable Effects but because we are humans these clever people pretend that those effects are not there and that it is "all in our minds".
Where is the theory that explains how cyanosis and peripheral neuropathy can be "of psychological origin"?

14. Many figures provided by the regulatory bodies are based not on actual scientific tests but on mathematically calculated probability.
Is the Minister certain that the figures relied upon can be scientifically validated?

PSD is content that all data modelling is supported by underlying studies on exposure, food residues and environmental effects. Where there is uncertainty the values used in the models will be conservative.

I trust that the above comments are helpful.

Comment : Should we be in any way pleased to see that the PSD is content?

Those of us poisoned by these chemicals are not content at all and we would very much like to see them declared on the food labels so that we can avoid further dangerous cumulative exposures.

Dated 29/4/2005

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