Many of the European Union's schemes to unite its member countries have involved standardisation of products and services. By creating specific standards for items such as foodstuffs, toys and electrical equipment, standardisation informs consumers, protects their safety and allows the free movement of goods throughout the European Union. However, the finer details of the standards have often been held up for ridicule (particularly by the British tabloid press) when, for example, some definition is proposed for what can be marketed as a sausage, or ice-cream1.

One thrust of European policy has been to tell consumers the ingredients of the products they buy. This allows consumers to make informed choices, such as avoiding products containing something they are allergic to. Many modern foodstuffs contain natural or synthetic food additives. The code of E-numbers was adopted as a sensible method of listing these additives, while avoiding the issue of translating them into the wide range of languages used in Europe.

European legislation laid down in the Council Directive of 21 December, 1988 on 'the approximation of the laws of the Member States concerning food additives authorized for use in foodstuffs intended for human consumption' states that:

For the purposes of this Directive 'food additive' means 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 be reasonably expected to result, in it or its by-products becoming directly or indirectly a component of such foods.

This could be paraphrased thus: A food additive is something deliberately added to food which isn't usually considered a normal ingredient, and which is likely to still be in the food (in some form) when you eat it.

Food additives such as vinegar, salt and sugar have been used for centuries to assist in flavouring, colouring or preserving food. Up until the 20th Century there were relatively few kinds of additives, but during the last hundred years there has been a massive increase both in their number and usage. It has been estimated that there are now over 2500 food additives in use around the world and about 100 more being proposed every year.

Many of the E-number additives are artificially produced, but there are also quite a few natural ones refined from various sources. The natural additives include several that vegetarians might wish to avoid (as they are, or may be, derived from animals), for instance E441 Gelatine2 or E120 Cochineal3.

E-numbers are used to indicate permitted food additives in the European Union. The numbers start with E100 (turmeric, a colouring) and most have three figures (eg, Exxx), though some go into the thousands, for example E1520 (Propylene glycol, a humectant4). Although the numbers can go this high there are numerous gaps, and there are only between 300 and 400 E-numbers specified in total. Each number specifies a particular additive, with blocks of numbers allocated to categories of additives with particular purposes.

The table below covers most of the larger groups of additive functions and their numbers, and must be read with the caveat 'lie mostly between'.

E-numbers were first introduced in Europe to help regulate the use of food additives, but are now used worldwide after the scheme was adopted by the Codex Alimentarius Committee5. Each number specifies a particular additive, but only ones permitted in Europe need to be prefixed by an 'E'. For example, additive 103, Alkanet6 isn't permitted in the EU, but is in Australia and New Zealand.

There is another European-inspired 'e' often seen on packaging, and associated with a number. This is the lower case e that appears after the volume or weight. It is the e-mark, and has nothing to do with additives.

Food additives are only permitted if they are deemed safe and perform useful functions (and many additives frequently have more than one function). There are about thirty main functions, from acidity regulators to thickeners, not all of which legally require the additive to be specified on labels or possess an E-number. For instance, many flavourings do not require an E-number.

Each additive is expected to be of a standard composition, and to this end JECFA7 provide specifications for every additive. It should be stressed that rigorous tests are carried out before an additive is passed as permitted for use in food, including the calculation of the Acceptable Daily Intake (ADI) - the amount of the additive that could be consumed safely each day throughout your life. This is usually done by finding the level at which no effect is observed and then dividing by a safety factor of typically 100. The purpose of the safety factor is to provide additional security in case some people are more sensitive than others.

Some may wonder why there are fewer E-numbers on packaging than there used to be. The reason is not that there are fewer additives, but rather that there has been a backlash against certain additives that have proved troublesome for some people. The most well-known of these is Tartrazine (E102) which has been linked to hyperactive disorders in some children. This bad press has tarnished the whole culture of concise E-number labelling.

While it is true that a small market has been created for products which are now 'additive free' (and which have a premium cost due to their shorter shelf-life), other products avoid the negative connotations of the E-number, and simply give the full name of the additive. There is no doubt in many people's minds that changes in dietary habits in the second half of the 20th Century have had dramatic effects on people's physical and mental health. These changes, particularly in the developed world, have included a move toward far greater reliance on processed and pre-packaged food. This kind of food has often relied heavily on a proliferation of additives which are used to ensure that the food has a long and attractive shelf-life. Whether the additives are themselves good for consumers is far from certain.

More information on what E-numbers are, what they are supposed to do, and what the possible downside of consuming them might be can be found from several websites:

• E Number Index at the UK Food Guide - a fairly comprehensive summary.
• Food Additives and Ingredients Association - 'pro'-food additive site.
• York College Hospitality and Catering Dept - 'anti'-food additive site.

As with any information garnered from the Internet, some of the assertions made should be taken with a pinch of salt (E251).