This much-publicised aspect of food production is well provided for in food legislation. A number of specific regulations exist to control any additives and contaminants that may be present in foods, either by direct addition or through indirect absorption. The adding of
colourants is an example of direct addition. Colouring can only be added to a food if the legislation for that food permits it, and only one or more of the colours listed in the regulations can be added. It may not be added in greater quantity than prescribed and it must comply with the standard of purity laid down in the regulation.
An example of indirect absorption is the maximum amount of lead that may be present in food, irrespective of the source. If you're about to argue that there shouldn't be any lead in your food at all, consider that the word 'source' includes the soil in which the plant is grown, the food consumed by an animal used for meat, or equipment in which a food is processed.
Chemicals- cause for concern?
An increasingly large number of additives and processing methods are used to produce the food we eat every day and understandably, public concern is once again on the increase. The amount of chemical substances used in food processing is possibly the major source of worry. Yet the use of these chemicals has been given the green light by legislators, or they would not be present in just about every food on our supermarket shelves.
Why are chemicals necessary in foods? In the simplest terms, because food itself is nothing but chemicals. In fact, the common foods we eat every day are such complex mixtures of chemicals that it would take a brash scientist indeed to assert that the composition of any single food is completely known. Even mother's milk - the only product designed by nature exclusively as a food for mankind - is known to contain more than 140 chemicals!
Perhaps it is worth pointing out that many of the chemicals which man produces are exact copies of those already found in nature. Just one example of this is vitamin C, a vital nutrient which of course occurs abundantly in foods such as citrus fruit and tomatoes. The vitamin C produced by man is identical to the natural chemical, both in terms of chemistry and efficacy, and its widespread use is the only reason scurvy is no longer the scourge of many populations whose normal diets do not provide sufficient of/this essential vitamin.
Interestingly, only a small proportion of pest resistance in plants is manmade. Plants develop their own defence mechanisms against pests and these include the use of natural toxins. Indeed, breeding crops for pest resistance may actually increase their natural toxin levels. For example, it is known that a pest-resistant potato had to be removed from the marketplace in the USA when its natural solanine and chaconine concentrations were found to have reached highly toxic levels. Similarly, a pest-resistant celery had to be discarded when workers handling it suffered outbreaks of dermatitis. It was belatedly discovered that the concentrations of 8-methoxypsoralen (a carcinogen) had inadvertently been increased ten-fold! Unfortunately, since new `disease-resistant' crops are not subjected to the same regulatory scrutiny imposed on man-made pesticides, we may never know how the risks and benefits of reducing pesticide use versus natural toxin consumption ultimately balance out.
To a large extent, the assumption that nature is benign has become ingrained in consumers' minds and even embodied in our regulatory codes. Biological materials are regarded as innocent until proven guilty, while man-made ones are assumed guilty until proven innocent. Without a proper body of balanced scientific scrutiny to back them up, assumptions such as these are not only simplistic - they could bedangerous.
However, solutions to problems such as the above will no doubt be found as more and more research is done in this area; there is no doubt that biotechnology will have an increasingly dramatic impact on the agriculture of the future. The genetic improvement of agricultural crops so that they become more resistant to disease, viruses and drought is clearly an important goal in a world already struggling to feed its billions of inhabitants. While the development of pest-resistant plants may never totally replace the need for agricultural chemicals, it could certainly help to decrease our dependence on them and so lessen the level of contamination to the environment - one of the majorconcerns of our times.