This topic is indeed a maze in itself. Apart from thousands of chemicals deliberately and legally added to foods, cosmetic and personal care, and of which the consumer is made aware by ways of labelling, there are many thousands of others that can be present in products, whether by accident or design, of which the consumer is unaware.

Hidden additives can include (but are not limited to) the following: indirect food additives; contaminants such as pesticide residues, nitrosamines, dioxane, ethylene oxide, formaldehyde; disclosed additives and ingredients; arsenic, lead, nanoparticles and products of irradiation and microwave cooking.

Indirect food additives are those that have accidentally entered foods in very small amounts during the processing, packaging or storing of food items. For instance, minute amounts of packaging substances may find their way into foods during storage. These include plasticisers used to make packaging films, to make canisters watertight and to protect cans from erosion. They also include a range of compounds that make machinery work efficiently. By law, manufacturers must document that the amounts present are considered to be so insignificant as to be safe and are within good manufacturing practice guidelines.

In the USA, over 3000 indirect additives are documented. They include chemicals such as acetone, acrylamide, benzene, formaldehyde, kerosene, styrene and toluene. Formaldehyde is used in modifying starch, in grocery bags and waxed paper.

Other chemicals called plasticisers are used to make plastics flexible and assist in processing. Plasticisers can migrate into foods, especially oily foods and those containing alcohol or acids. Migration can be speeded up by heat, so cooking foods in a plastic container in a microwave oven is not a wise thing to do. Some plasticisers called phthalates (pronounced thalates) are highly suspected of causing cancer, infertility and birth defects. Dibutyl phthalate (DBP) may be found in foods as a result of migration from plastic wrap, although food wrap produced in Australia apparently no longer contains it. Apart from their use in plastics, phthalates can be found in some hairsprays, hair gels, nail polishes, perfumes and fragrances. Phthalates are not listed on product labels. The European Union passed a law in 2004 that cosmetics and personal care should not contain phthalates.

Some hidden additives can be created during the manufacture of certain ingredients or be the result of an interaction between ingredients in the finished product. The contaminant, nitrosodiethanolamine or NDELA found in some cosmetic and personal care products is one example. It is one of a group of contaminants known as nitrosamines. Nitrosamines have been recognised for at least thirty years and are created when nitrosating agents, such as nitrates and nitrites, react with amino acids (the building blocks of protein). Althugh they can be removed from ingredients during manufacture, this is not always done. Other types of nitrosamines can be found in cigarette smoke, car interiors, processed meats and industry. All nitrosamines have the potential to cause cancer in many parts of the body.

Another carcinogenic contaminant that may be foundin cosmetics and personal care is 1,4-dioxane. It can occur in products such as hair shampoos and conditioners, cleansers, soaps and lotions containing detergents or particular types of surfacants and is easily inhaled or absorbed through the skin. Dioxane is unintentionally created during the manufacturing process howeever it can be removed in the final stages of manufacturing by a process known as 'vacuum stripping'.

Although mosts reputable companies do produce products that are largely free of diooxanes and nitrosamines, there is no way of knowing whether a chosen product is safe by simply reading the label. Few people will argue that toxic synthetic pesticides and herbicides serve any useful purpose in or on the foods we eat after they leave the farm. Debate however surrounds the levels of contaminant residues permitted and the extent to which these 'traces' of chemicals can be harmful. Regulations dictate the maximum levels of each pesticide allowed in or on foods. Some scientists believe that the daily consumption of foods containing even minute traces of pesticides, such as organophosphates, can lead to the accumulation of dangerously high levels in body organs. Brief exposure of salmon to 1 part per billion of certain carbamate or organophosphate insecticies is known to affect signalling pathways leading to alteration in homin behavious with obvious implications for predation, feeding, mating and olfactory imprinting.

In the USA in the late 1990s, the Environmental Working Group, using relevant data on food consumption and pesticide residues in food, concluded that 9 out of 10 American children from the age of 6 months to 5 years ingest organophosphate pesticides in their food each day (Our Bodies, Our Landfills by Francesca Lyman, 2003). Kris Thayer, a scientist with the Environmental Working Group and one of the studies authors, pointed to new evidence showing that simple dietary changes can reduce one's exposure. She cited a study that found that feeding children organic food reduced their exposure to pesticides by 6-9 times. Some of the chronic effects of pesticide exposure include cancer in both children and adults; birth defects; genetic damage; neurological, psychological and behavioural effects; blood disorders; chemical sensitivities; reproductive effects; and abnormalities in liver, kidney and immune system function. These chronic health effects can develop following either an accute poisoning or low-level exposure over a period of time. According to a 2003 report by the organisation Health Care Without Harm, pesticide poisonings are frequently misdiagnosed or unrecognised, largely because most health care providers recieve minimal training in environmental illnesses and few people even know when they have been exposed to a pesticide.

One of the relitavely new technologies expolding into the 21st century is nanotechnology. Nanotechnology is engineering at the atmic level and works on a scale of up to 100 nanometres. One nanometre is a billionth of a metre, or about 1/80,000 the width of a human hair. A grain of sand is one million nanometres across, the same as one millimetre. Nanotechnology is said to be the next thing in cosmetics and skincare. Very small particles of titanium dioxide are already being used in sunscreens and moisturisers because they disspear completely into the skin, providing an invisible protective layer. Product labels do not inform consumers that some ingredients are present as nanoparticles and are therefore hidden. As you read on you will learn that this may have potential effects on health. There are currently over 100 commercial products based on nanotechnology including selfcleaning glass, synthetic bone, odour eating socks, tyres, pharmaceuticals, and anti-ageing cosmetic creams.