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Troubled waters
Now, we could regale you with a series of cliches about water being the VERY substance of life, but we all know that. The human body is made up of 70% water, and it's essential to all of our basic body processes. World health standards tell us that every human being requires a minimum of 24 litres of the stuff daily. We can't get away from it. So what if our water contains things that are detrimental to our health and the environment? What then?
There is increasing worldwide concern about the presence of environmental oestrogens in water supply. An environmental oestrogen is a substance which mimics the structure and action of oestrogen, the female hormone. Oestrogen is a hormone created in the body, which is responsible for the development of many secondary female characteristics in women. These include the maturing of the uterus, the development of breasts and the onset and regulation of menstruation. Oestrogen is also present in small quantities in male testes, although its use there is less clear.
Substances that mimic the structure of oestrogen occur naturally, in plants such as clover, soybeans and other legumes, whole grains and many fruits and vegetables. Clearly, humans and animals have been exposed to these substances for as long as we've been eating these foods, without too many adverse effects. However, there are artificial oestrogen mimicking substances in by-products of any number of industrial substances: pesticides, batteries and certain plastics and paints. When these substances enter the water supply, they can have effects on the environment, and on human and animal health.
Liesl van der Merwe wrote her master's thesis on the effects of oestrogen and EMS's in the South African water environment. "Animals are used in research as models to which one can extrapolate to humans, there has been increased incidents of testicular cancer, sperm abnormalities, viability, morphology, motility that has decreased," says Liesl. "There has also been increased incidents of breast cancer in women. DDT is a classic example, where it bio-cumulates in the environment in sedimentations and eventually higher up in the food chain humans get effected. If you have a lot of minute quantities in the environment, you get bio-cumulation via the food chain". So those are the potential effects, but how real are our risks of exposure, and just what exactly IS coming out of your tap? Karl Lubout from Rand Water comments: "The drinking water quality on the Rand is determined by two different issues; firstly the raw water supply that we get from the Vaal Dam which is an excellent source of supply and has a very high quality, secondly the purification process which then brings the water(3.4) quality up to international standard for drinking purposes." Raw water is pumped to the Zuikerbosch purification works from the Vaal Dam and in the first phase of purification - called sedimentation - lime is added to it, causing the bigger, visible particles to join and sink to the bottom as sediment.
Up here on the Rand, we seem to be in the clear for now, as are other areas served by water boards where water is not recycled. But what about those areas that re-use water, or those people living in informal settlements, and using unprocessed water? Many of us have these water jugs in our homes, and we trust that they're removing impurities from our water. But are they? "In the South African contexts, water purifiers are used to remove things like taste and odour specifically the chorine taste in water which some people don't like, but from a health point of view, no improvement in the quality or status of that water can be achieved," says Karl Lubout.
If you're really concerned about EMS's, there's a lot of information at www.tmc.tulane.edu, the website of the University of Tulane. But take heart, research is ongoing, and we're a long way from Samuel Taylor Coleridge's nightmare, "Water, water everywhere, nor any drop to drink!."
Contacts
Liesl van der Merwe. Medical Natural Scientist |
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Contents and images © 1998 All rights reserved |
As with all hormones, the levels of oestrogen in the body are crucial. Too little will have a detrimental effect on female reproduction and characteristics, and too much can cause disease, reproductive abnormalities and even cancer. It can also cause feminisation of males.
While research into the effects on humans are in the early stages, well-documented research shows a detrimental effect on fish, both male and female, as well as other aquatic animals from oestrogen mimicking substances, or EMS's.
Once PH balance of the water has been stabilised, Chlorine and Ammonia are added to kill off the bacteria, ensuring that the water is safe to drink. Quality control is exercised throughout this process to ensure a high level of clarity.
So if you're really concerned, the trusty old kettle may be your best defence. Boiled water may taste a little flat, as it has had the oxygen removed from it, but the act of boiling water not only kills bacteria, but it will break down many chemical compounds, including some EMS's.