CHEMICALS IN FOOD


A person doing work might eat twice the amount of bread which a sedentary person might consume and thus get twice the dose of Vitamin D, although the vitamin requirements of both persons might be the same and considerably smaller than the amount supplied in the bread to either. Fortunately there were no deaths.


(Annual Report on the State of the Public Health).

GROSS adulteration has given place to scientific “treatment” of food (sometimes described as ” sophistication”) at the hands of skilled chemists. Whereas fifty years ago it was the rarest thing for a food manufacturer to employ a chemist, now every factory of any consequence is equipped with its research laboratory, and there are actually more chemists employed in the various branches of the food industry than in other single industry in the country.

The result is that every sort of artifice is being used, in competition with rival firms, to “improve” the appearance, colour, taste, keeping qualities, etc., of food. For the most part such artifices are above suspicion and constitute an obvious advance in manufacturing practice, but on the other hand many of them are open to serious question and are causing some uneasiness among those responsible for the wholesomeness of food supplies. This is new problem in supervision and in the administration of the Acts controlling adulteration of food.

It is not a question of any immediate and obvious injury to the health of the consumer. Such cases can be, and are, dealt with effectively under the existing Act. It is more a question of whether practices are likely gradually to affect the digestive and metabolic functions of the human body, and to become, to greater or less extent, a contributory cause of lowered vitality, impaired physique, debased nutrition or indifferent health. It many be argued that it for the physiologist to say what is, and what is not, injurious in food.

But the physiologist is here at a disadvantage. His opportunities of direct experiment on the human body are limited. It is eighty years since the French Government tried the effect of zinc salts in the food of Spanish prisoner. Even where experiments on men are possible, the effects, good or bad, of a particular food or food ingredient are liable to be obscured by an immense complex of variable factors. The experimenter must proceed cautiously, step by step, and draw conclusions by inference, by analogy, by carefully controlled experiments on animals.

Some of the problems may be quite insoluble until physiological science has advanced into a new era of fundamental discovery, and guidance must be sought from the experience and intuition of those who must about the internal economy of the human body. Meanwhile, is it the manufacturer of the consumer who should have the benefit of the doubt–the manufacturer whose interest in the matter is purely financial, or the consumer whose interest in the matter is personal and vital ?.

Much of what has been written and said about modern treatment of food is undoubtedly prejudiced, abetted by food cranks, faddists and interested parties, but it will be conceded by everyone that if there is a reasonable doubt as to whether a particular process is liable to reduce in any way the nutritive value of a food affect adversely the health of the consumer, it is the consumer who is entitled to the benefit of the doubt.

As instances in which there exists a legitimate suspicion that a commercial process may involve a definite risk to health or debasement of nutritive value I may cite (a) the fumigation of food with toxic gases to destroy insect pests, (b) the presence of heavy metals in food due to the materials or containers used in the manufacture and storage, (c) the increasing used of poisonous insecticides and fungicides in agriculture and horticulture, (d) the treatment of flour with bleaching and “improving” agents, (e) “fortification ” of food by artificially added vitamins, (f) the uncontrolled and unregulated exposure of food to ultra-violet rays, or (g) the introduction of new synthetic colours and flavours.

It is not on the score of possible direct injury to health that present-day scientific treatment of food is raising difficult questions. Innumerable processes have been introduced in which the danger lies not in any direct menace to he health of the individual, but in the possibility that the nutritive value of the food has been adversely affected, or that the food has been so treated as to give a totally false impression of its nutritive value.

This tendency must be considered not from the individual but from the collective viewpoint. The possible loss to the individual consumer, where a particular food is concerned, may seem unimportant or even trivial, but the sum total of loss when all such food are considered may be considerable. The effect on the individual may be difficult to gauge, but the nutrition of the people as a whole may be seriously affected.

Colour in foods is recognized as being an important factor from the salesmans viewpoint. This is seen more especially in confectionery, where the colours used are mainly reds, oranges and yellows associated with different fruit flavours. It is fairly widely known and generally accepted that all these colours and flavours in confectionery, and many of these in preserve, jellies, etc., are artificial, and it is doubtful whether many purchasers are really led to believe that fresh fruit has been used in their manufacture.

There is, however, another aspect of colour in food which is of primary importance to the public. For instance, the bleaching of flour may involve the partial destruction of the yellow colouring matter, carotene, which is one of a large family of “lipochromes”, yellow and orange fast- soluble colours occurring widely in nature. They are present in all green vegetation, where their colour is masked by the green of chlorophyll.

Butter and egg-yolk owe their yellow colour to these substances. Carotene has been shown to be a most valuable foodstuff, in that it is probably the primary source from which the body obtains most of its Vitamin A, and it is highly probable that the lipochromes of butter and egg-yolk have similar properties.

The public knows by long experience the value butter and eggs, and subconsciously associates the rich yellow colour of certain food with the presence of butter or eggs. This preference for a certain colour as indicating superior nutritive value was taken advantage of many years ago by margarine manufacturers, and it was found necessary to impose a rigid system of labelling for margarine. At that time, no doubt, the motive for restrictive action was partly the safeguarding of the public health, and partly the protection of agricultural interests. It is only lately that thee public health aspect has become more obvious.

Logically the labelling system adopted for margarine should be extend to custard powders, coloured a rich golden-yellow but otherwise consisting only of starch and sugar with a little artificial flavouring material. Egg powders, again, possessing the visual appeal of the genuine article, may contain absolutely no egg at all. The public does not understand the trade distinction between “egg powder” and “powdered egg”.

There is no objection to these articles as wholesome foods, but they are coloured and labelled in such a way as to lead the consumer to believe that he is getting an article of superior nutritive value.

There is a difference in nutritive value between summer and winter butter. The former is strongly yellow, due to plentiful grass feeding, ad is more nutritious than the pale-coloured butter of stall-fed cow in winter. Normally the consumer would show preference for rich colour as indicating a higher quality of butter, but it is now customary to add artificial colour to winter butter.

Where the nature of a food does not admit of artificial colour being used as an indication of high quality, the food is often advertised as being of specially high vitamin content. Instances abound where the name of the product or its description in advertisement implies the possession of high nutritive properties which have little of no foundation in fact.

These thing are not quite in the same category as the ordinary commercial advertisement which habitually exaggerate the value of its wares. they must be looked upon as likely to disturb the normal intake of special ingredients and so bring dietetics or education propaganda into disrepute, making more difficult the dissemination of sound knowledge on nutrition.

There is a tendency at present time for manufacturers to avail themselves of the publicity value of recent vitamin research by adding vitamins empirically to a variety of food without due consideration of the results which may accrue from such haphazard practices.

If a halt is not called to this indiscriminate dosing of foods with vitamins, there is a possibility of a disturbance in the balance of nutrition which may have wide-reaching effects and which it is not unreasonable to contemplate with some uneasiness.

As an example of this attempt to “improve” the nutritive value of a food (and incidentally its selling appeal to the consumer) the addition of irradiated ergosterol (Vitamin D) to bread may be mentioned. Such bread is already on the market and recently an important firm of bakers contemplated the addition of irradiated ergosterol to their bread in amount sufficient to make its Vitamin D content equivalent to that of bitter, weight for weight.

This would mean an unusual ingestion of Vitamin D by the consumer when it is considered that many pounds of bread are eaten for each pound of butter consumed. A further objection is that all consumers of the bread would take the Vitamin D which it contained whether they required it or not. The Purpose of bread is mainly to supply energy and a certain amount of protein an the quantity of bread in the diet varies in accordance with these requirements. Consequently, consumers would not only be compelled to take vitamin D, but would actually have their dose regulated not by their requirements of Vitamin D but by their energy requirements.

A person doing work might eat twice the amount of bread which a sedentary person might consume and thus get twice the dose of Vitamin D, although the vitamin requirements of both persons might be the same and considerably smaller than the amount supplied in the bread to either. Furthermore, the body requirements of Vitamin D differ according to age. The needs of an adult are less than those of a growing child, yet an adult, who probably consumes more bread than a young child, might well be getting a larger dose of the vitamin than the child, a complete reversal of what should be the case.

Another aspect of the matter is the risk of hypervitaminosis. Although, if diet is normal and contains a sufficiency of milk, the danger from hyper-vitaminosis in children would not appear to be great, there is evidence which suggests that under certain conditions (especially when the diet is lacked in milk or when the calcium intake is high and the phosphorous intake low), the risk of hyper-vitaminosis has to be seriously considered.

It is not impossible that such condition might occur in children receiving a faulty diet poor in milk and consuming appreciable quantities of bread dosed with irradiated ergosterol.

It is desirable, therefore, that the administration of Vitamin D should be capable of control and this could certainly not be ensured if Vitamin D were continually being administered in a staple daily food like bread which is eaten in varying quantities and the consumption of which is governed by needs entirely different from Vitamin D requirements. If the practice of adding irradiated ergosterol to bread became at all general, it might become impossible in some districts at any rate to obtain ordinary bread free from this substance.

A further outbreak of lead poisoning from the drinking of cider was reported in September from Devonshire and clinical notes on ten or twelve cases have been published. The outbreak was, as in former cases, traced to the use of lead pipes for conveying cider from barrels to the engine at the public house bar.

Cider that had remained all night in the pipes was found to contain appreciable amounts of lead. It was stated that the pipes were tin-lined and that the publicans had been assured by the makers that such pipes could not possibly lead to contamination of cider.

In any case the practice of allowing cider and beer to come into contact with lead is reprehensible. Unavoidable sources of lead in foods and drinks are sufficiently numerous without being multiplied unnecessarily. Injury to health from traces of lead dose not necessarily begin only with obvious symptoms of lead colic. there may be, and probably are, lesser degrees of lead poisoning, manifested only in generally impaired health and vitality, and not obviously attributable to any definite cause. Pipes properly lined with a thick coating of are available.

Another case has occurred of antimony poisoning from the use of enameled vessels. At a Christmas dinner to the staff of a well known London hospital, lemonade was served which had been prepared in new enamelled iron jugs. During the progress of the dinner, and subsequently one after another of the hospital staff was seized with violent sickness, until eventually sixty-five out of seventy were more or less seriously affected.

It was found that acid lemonade had attacked the enamel of the jugs and had become highly charged with soluble compounds of antimony. Fortunately there were no deaths.

George Newman