Chemicals in our food – what are they?
There’s a lot that’s been written about why we should – and for that matter why we shouldn’t – be eating organic food these days. I don’t intend to go into a monologue covering off on every one of these arguments. Instead, I thought it might be worthwhile taking a quick look at some of the chemicals that can find their way into our food chain. But first, let’s consider why they’re there in the first place.
Fertilizers and pesticides are the two main sources of introduced chemicals into our food chain. Fertilizers are intended to increase plant foliage and generally to make plants appear larger and more healthy. Research has found that synthetic fertilizers lower the nutritional content of fruits and vegetables and also have the potential to reduce human reproductive capabilities.
Pesticides are designed to control and kill unwanted organisms. A wide range of pesticides exists. The more commonly known pesticides include:
- Herbicides, which are used to destroy, prevent, or limit the spread of vegetation
- Insecticides, which are used to destroy or prevent unwanted insects; and
- Fungicides, which are used to destroy or regulate the effect of a fungus.
Pesticides of concern due to their toxicity and the environmental hazard they pose include:
Organophosphates – a family of highly toxic pesticides that work by killing the brains and nervous systems of insects. Organophosphates are still widely used and have been found in disturbingly high quantities on many fruits and vegetables. Research has found that these chemicals can also harm the brains and nervous systems of human beings.
Dieldrin – an organochlorine insecticide which, although now banned in the United States, is highly persistent and still present in many soils. It was introduced to control insects in cotton, corn and citrus crops, and also to limit the spread of diseases carried by insects, such as mosquitoes and tsetse flies. Classified as a persistent organic pollutant (POP), it has the capacity to remain in the environment and in human body fat for long periods of time.
Lindane – a broad spectrum organochlorine insecticide that kills insects by stimulating their central nervous systems causing trembling, hyperexcitation, loss of coordination, paralysis, and eventually death. Although banned from use in agriculture in the United States, it is still used in many pharmaceutical products, for example in shampoo formulations designed to treat head lice in children. It is persistent in the environment, tends to bio-accumulate along food chains and has been linked with breast cancer and Aplastic anaemia. A campaign aimed at removing lindane from pharmaceutical products, which you can get involved with, is currently being waged by the Pesticide Action Network of North America.
Methomyl – a broad-spectrum insecticide from the carbamate group used to control insects in a wide range of crops. As a carbamate, it works by inhibiting cholinesterase, an essential enzyme for proper functioning of the nervous system. This acutely toxic insecticide is found in many fruits and vegetables. It is also a suspected endocrine disruptor and a potential groundwater contaminant,
Maleic Hydrazide – a herbicide used to prevent crops such as onions and potatoes from sprouting. It contains small quantities of hydrazine, a known toxin, which has the potential to leak into water reservoirs.
It’s important to remember that as time passes new knowledge comes to hand. Many chemicals that were once considered acceptable for use within the food chain are now specifically banned. Unfortunately, many of these are not banned until such time a positive correlation exists between the specific chemical in question and an adverse human health impact.
And although many of the more toxic chemicals have, due to our more enlightened frame of reference, been banned in much of the developed world, increasingly we’re sourcing our food from a range of countries that do not necessarily practice the same standards required of farmers in developed nations. Not all of these countries have phased out the use of chemicals many of which are now known to be carcinogenic and are banned in developed nations.
Is organic food entirely free from chemical additives? Well, it certainly aims to be. But, it’s important to realize that organic agriculture is a system. While no system is infallible, organic farming practices specifically precludes use of the pesticides, herbicides, fungicides, fumigants and defoliants routinely used on conventional farms. And that’s a pretty good starting position.
I’ll leave you with something I’ve always found fascinating. And that is, while it isn’t that difficult to find people advocating the use of fertilizers and pesticides to facilitate industrial agricultural pursuits – and even research concluding that agricultural chemicals don’t pose any risk to human health – you won’t find too many people (and certainly no research) claiming that these chemicals are good for your health. So, I for one will stick with the organic approach. It’s simple and it’s uncomplicated. And I think that’s just the way nature intended it to be.
- Moses, Marion, Pesticides and breast cancer, Pesticides News 22, December 1993, 3-5
- International Programme on Chemical Safety, Environmental health criteria 124, Lindane, World Health Organization, Geneva, 1991.
- Gosselin, R. E., et al. 1984. Clinical toxicology of commercial products. Fifth edition. Baltimore, MD: Williams and Wilkins.
- Dickens, F. , and Jones, H. E. H. , Brit. J. Cancer, 19, 392 (1965).
- Davies, D.R., Organophosphates, affective disorders and suicide, Journal of Nutritional & Environmental Medicine, 1995, 5:367-374.
- Parron, T., et. al., Increased risk of suicide with exposure to pesticides in an intensive agricultural area: A 12-year retrospective study. Forensic Science International, 1996, 79:53-63.
- Pesticides News No 31, March 1996, p11.