Pesticides are used both before and after harvest

Pesticides in Food - a brief history.

Our ancestors are reported to have stored grain in pits in the ground. Science suggests that the grain would have been protected from insects by the accumulation of inert gas which is heavier than air.
With the invention of the threshing machine grain was commonly stored in 4-bushel sacks which allowed the storage of relatively moist grain. If insect infestation or hot grain was found sacks were emptied and the contents turned with shovels until the problem was resolved.
The combine harvester produced a revolution in grain handling which moved from bags to the bulk handling of loose grains. Grain drying systems and their augers and conveyors allowed very large tonnages to be stored in giant silos but the real problems of insect control began.

Adulteration of foods with poisons had concerned the Trading Nations for centuries and one of the earliest attempts to prevent the poisoning of food supplies were UK Acts introduced in 1725 and 1730.
Sampling and testing of foods began with the Adulteration of Food and Drugs Act of 1872 in London[1].

The First World war brought the fear of Chemical Warfare and it was realised that entire populations could be at risk from poisons introduced in food. The Food and Drugs Act of 1938 "Prohibited the addition of substances to foods so as to render the food injurious to health"[1].

The Food Drugs and Cosmetics Act of 1938 prohibited the cross-border trade of food adulterated with known Poisons but regulators believed that residues from spray operations could be permitted and thus tolerances were allowed for substances such as lead, fluorine, parathion and benzene hexachloride. DDT was also permitted below certain limits in 1945.[1] This opened the door for the use of such chemicals in grain stores and then to the incorporation of such poisons into the grain itself.

Residues then became undeclared food additives and poisoning food now became lawful.

The end of the Second world War brought the discovery of the organophosphorus Nerve Gas stocks in Germany and I.G. Farben was divided by the allies to form many of the chemical companies now responsible for Agrochemicals.[2] The science was a valuable resource and the allies made use of the expertise the Nazis had obtained by human experimentation in the concentration camps.

Concerns about the safety of commonly used agrochemicals were raised in the 1960s following the publication of Rachel Carson's book "Silent Spring" and with environmental damage proven the organochlorines began to be replaced by OPs which were said to be less persistent in the environment despite the known greater risks to man.

In 1969 Japanese scientists discovered vision problems in children living in areas of high agricultural OP use[3] but by the mid 1970s the OP insecticides were becoming more widely used in grain stores not only treating infestation by fumigation but by admixture during harvest as a preventative measure.

Civil Servants prepared an 80 clause document suggesting curbs on the use of pesticides but the effect would have been to further raise food prices and so the Heath Government shelved the idea[4].

Government agencies[5] advised farmers that grain would not be permitted into intervention stores if any live insects were present and that pesticide treatment was essential to ensure sales.

Rising yields combined with fewer farm staff available to monitor stored grain and the development of resistant insect strains only served to increase the pressure on farmers to incorporate pesticides.

In 1977 it was reported that OPs could damage the frontal lobes of the brain [6] and later that grain workers had a higher than usual risk of contracting lymph cancer.[7]

In the early 1980s the OP herbicide glyphosate was promoted for use on the growing crop to kill weeds which can make harvesting difficult.[8] This systemic herbicide moves through the entire plant so that the roots of even persistent weeds are killed. It also has insecticidal properties.

With the introduction into the UK of foods produced from Genetically Modified crops there was a need to raise the permitted levels of glyphosate residues in the final food by some 200 times the original levels accepted as "safe". All attempts to prevent the contamination of the UK environment with crops designed to withstand the actions of this chemical have failed and the trials continue.

Systemic insecticides used on the growing wheat crop were strictly controlled with pre-harvest intervals of up to 21 days and yet those same active ingredients used as admixture in grain stores had no withholding times. Grain can be eaten immediately after treatment yet product labels warn that sacks which had contained treated grain cannot be used even to contain grain to be used for food - the very grain which made the bags unsafe for re-use[9].

Various methods are advised for applying the chemical to the grain but all can result in excess incorporation rates. Dust formulations may be incorporated "by hand" which entails mixing a calculated quantity of the pesticide into the grain to the depth of a metre with a shovel. The potential for extremely high spot rates by this method is enormous and given the tonnages involved such excesses could effect thousands of humans and animals. Damaged bags containing pesticide have reportedly been found in consignments of grain. Dust can also be applied by a vibrating applicator which must be calibrated to give the correct flow for a predetermined rate of grain transfer. Local experience shows that this too can lead to grossly excessive incorporation rates. Similar methods are used for liquid chemical which is sprayed onto the moving grain through nozzles but excess application is still possible.

Farmers are not the only groups to treat grain in this way. Transport firms have been known to re-treat grain, major grain stores also add pesticides and reports from farmers suggest that some baking companies have even insisted that grain is treated before purchase despite the option to refuse consignments containing insects, presumably to prevent later infestation without additional cost. Intervention stores reportedly also add further treatments in order to establish the 5 year storage protection period. It is no surprise then that the "Grain Passport" system was introduced in the late 1980s in an attempt to reduce the residue levels. Reports suggest that the efforts made by farmers to declare treatments end at the buyers, where the passports are destroyed and grain may still be given additional treatments.
The consumer is never informed that they are purchasing food which contains a "hidden extra"

The regulatory bodies attempt to reassure consumers that monitoring will detect any excess applications and so protect them but this is far from satisfactory. It is claimed that about a million tonnes of grain is treated post harvest with incorporated insecticide annually. That is the equivalent of more than a billion loaves of bread.
Only a few grammes taken from almost 300 loaves have been tested for residues and some of those are organic loaves in which they claim to find OP residues due to "background levels".
It is admitted that up to 50% of the pesticide added to grain can be found in the bread.
A split bag or split container of pesticide can accidentally cause an excess dose to be added to a a few hundred kilograms of grain which may never be detected.
That grain could give dangerously excess doses to hundreds of children in food which they may eat every day for several days.

Even the BMA reported in 1991 that baby's rusks contained grain store OPs and that beer brewed from treated barley might have an "unexpected extra kick"[10]

The writer was a farm manager and had never understood why when using such chemicals he suffered headaches, breathing difficulties with diarrhoea, and stomach upsets, despite wearing more than the recommended protective clothing. After a particularly difficult year, when a pesticide resistant mite infection necessitated repeated applications to the structural surfaces and the first incorporation of pesticide dust into grain destined for cattle feed, his eyes became temporarily sensitive to light.. The cattle had then suffered with apparent shortage of magnesium and had become agitated resulting in the death of one animal until magnesium supplements were used. A copper problem which caused infertility required additional energy foods and mineral supplements.

In 1992 the writer was later poisoned by one of these chemicals to the extent that he is now regarded as permanently disabled. Finding a distinct unwillingness on the part of the authorities and the medical profession to understand and recognise his problems he has become deeply involved in the scientific research and is shocked by what he has discovered.

A major OP insecticide added to grain post harvest had not even undergone a full review until 1997 - a full twenty years after it was first reported as used in grain fed to the people of this country. Despite evidence given to the authorities that commercial OP formulations are actually extremely persistent and remain active many years after dilution the official review[11] still claims half-lives of days in water and hours in sunlight. Adverts by the manufacturer claim that treated grain is protected for "up to 12 months"[12] but more worryingly the official review document[11] admits that the studies reported cannot apply to current commercial formulations. Commercial confidentiality demands that the full ingredients cannot be declared but it is admitted that some co-formulants present health hazards in their own right. The writer was surprised to find that the long-term effects of repeated low dose exposures just as occur when eating treated grain have been recognised for much of the last century[13] and yet officials in Government still deny knowledge of such problems.

More worryingly the known action[14] of these chemicals on the basic biological processes of life itself explains all of the problems reported by sufferers since the energy processes which control our metabolism and upon which our lives depend involve the continuous coupling and uncoupling of phosphorus, oxygen and carbon bonds. DNA itself is regarded as an organophosphate.[15]

Experimentation has shown partially irreversible brain damage, sperm damage in experimental animals at all tested levels, the mutation of bacteria, damage to the proteolytic enzyme system and the mitochondria with the potential for a host of diseases now linked to protein failures, including cancer, hormonal imbalances, asthma, obesity, anorexia, CJD, Alzheimer's, auto-immune disease and ageing.

Interestingly the major foods to which individuals have reported allergic reactions, which can sometimes be fatal, are peanuts, wheat, milk and eggs. Peanuts are known to absorb high levels of pesticides.
Wheat and other grains have pesticides added to them after harvest.
Cows which produce milk are regularly treated with pesticides and the food they eat contains pesticide residues, much of which is excreted in the milk.
Birds are particularly susceptible to some pesticides in food and the environment.

Permitted residues levels are often highest in all these foods.

In 1998 USA scientists called for an immediate ban on OP chemicals[16] which are used in the UK as grain additives because of the vulnerability of children. UK regulators have ignored that call.

The Chairman of the UK Food Standards Agency is aware of the serious flaws in the data for pesticides used on and added to foods.
The Food Standards Agency have a responsibility to ensure that the food we eat is safe and that it is produced to high standards.

Recently he produced a published article on Genetically Modified crops in which he stated that "calls for a worldwide moratorium seem to me to have no moral or practical credibility."
Shortly after that he is reported as having declared that organic food "is a waste of money" and that there was "no evidence" that organic food is healthier or more nutritious than conventionally grown food.

We must ask this regulating body why it is that its members hide that evidence from the general public?
We must also ask why the Government itself has warned the public to peel fruit at vegetables in order to reduce the proven high residues of pesticides.
We might also ask them why pregnant mothers and those treated with chemotherapy are now advised to avoid food containing pesticides where ever possible?

Perhaps the most important question needing an urgent answer is why the Chairman remains in his post as a supposedly independent food safety expert when he holds such obviously incorrect and biased views?

For a study on the inadequacies of pesticide testing click here


[1] Encyclopeadia Britannica 1959

[2] "P" is for Pesticides. Lang & Chutterbuck 1988

[3] Saku Disease. Ishikawa 1971

[4] Anatomy of Agriculture. Wormell 1978

[5] ADAS advice publications for UK farmers various dates

[6] Effects of Chronic OP exposure on the Central Nervous System. Korsak & Sato 1977

[7] Immune surveillance, OP exposure, and lymphomagenesis. Newcombe 1992

[8] ADAS advice publications for UK farmers various dates and current advertising

[9] Chemical company product label Instructions for use and precautions

[10] Pesticides Chemicals and Health BMA publication 1990 / 1992

[11] Pesticides Safety Directorate Evaluation Document 1997

[12] Zeneca Enterprise advertising leaflet February 1994

[13] DSS Notes on the Diagnosis of Prescribed Diseases C3 and Zuckerman report 1951

[14] HSE Medical Series Guidance note 17 1980, 1987 and 2000 versions.

[15] The shocking history of phosphorus, a biography of the Devil's element. Emsley 2000

[16] Overexposed - organophosphate insecticides in children's food.Wiles,Davies & Campbell. 1998

Dated 16/9/2000

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