by Eugene Bezuidenhout
1. What is the endocrine system?
- The endocrine system is also referred to as the hormone system. Hormones in humans and animals have an important function. They regulate the body’s various processes, such as metabolism, growth, and reproduction. An example of a hormone is insulin, excreted by the pancreas which breaks down sugar. Another is adrenalin, excreted by the adrenal glands and pumps us up to handle stress or danger. The endocrine or hormone system is made up of the endocrine glands:
- Hormones are part of the endocrine system. Hence, hormone disruptors are also called endocrine disruptors. This concern originated with oestrogen, the female hormone which is also sometimes referred to as oestrogen mimics. Recent studies also include the male hormone androgen and androgen disruptors.
What are endocrine disruptors?
Endocrine disruptor chemicals – EDCs (sometimes referred to as gender benders ) are chemicals which mimic oestrogen or other important hormones in humans and in wildlife. They can cause endocrine disruptive effects at exposure levels up to a million times lower than carcinogen exposure levels of concern.
Disruption may occur in various ways: 1. Some chemicals my mimic natural hormones which “fools” the body in either over-responding or under-responding to the stimulus at the wrong time. 2. Other may block the effects of hormones. 3. Some may directly stimulate or inhibit the production of hormones causing overproduction or underproduction.
In the mid-seventies an EPA (Environmental Protection Agency) chemist found excreted aspirin, caffeine, and nicotine in sludge at a sewage plant in America. At this stage they didn’t think it worthwhile to pursue the matter. Ten years later German environmental scientists discovered clofibric acid, a cholesterol lowering medicine in groundwater downstream from a German sewage plant. Further investigation lead to the discovery of two different medicines which control the lipid concentration in blood, as well as analgesics in local surface water. In the late nineties Swiss scientists found cholesterol drugs in their groundwater, lakes and streams. Between 1999 and 2000 the United States Geological Survey analysed the water of 139 streams across the US and found hormones in 80% of the samples analysed. In Canada researchers found cancer drugs and anti-inflammatory drugs, while in the UK everything from Ibuprofen to antibiotics was found in sewage and streams.
Scientists around the globe soon realised that pharmaceutical products posed a new environmental pollution. Pharmaceutical industries, hospitals and clinics are all involved. Even households are not innocent. Many unused medicines are disposed of via toilets, contaminating sewage systems. Not all ingested medicines taken by humans are always metabolised completely by the body. The rest passes through and is flushed down the toilet and ends up in sewage systems. Sewage wastewater is treated before it is discharged into reservoirs, rivers or lakes. A portion of this water is treated at drinking water treatment plants and distributed to consumers, but most treatments do not remove all drug residue.
Ingredients/constituents of antibiotics, antidepressants, birth control pills, cancer tablets, tranquilizers, analgesics and hormones were found in various concentrations in water. Not only is medicine a serious concern, but cosmetic products are also posing a threat. The last decade proved that agricultural pesticides and DDT caused serious reproduction problems in animals and humans.
Although scientists are still pursuing research on EDCs, the following conditions have already been described:
1. Drugs in the environment cause bacteria to become resistant to antibiotics resulting in super-resistant bacteria. 2. The United States Geological Survey’s fish pathologists revealed in a study that due to pollution, 80 percent of male largemouth and smallmouth bass in the Potomac River produce eggs. 3. There is ample evidence from research conducted during the past decade that some chemicals have potent effects on wildlife at concentrations far below parts per billion. For example, estradiol, the female sex hormone (and a common water pollutant), can alter the sex characteristics of certain fish at concentrations of 20 parts per trillion. 4. British researchers suggest that oestrogen, the female sex hormone, is primary responsible for deforming reproductive systems of fish. Male trout living below sewage treatment plants had the female egg protein vitellogenin. U.S. researchers came to the same conclusion after studying carp in Las Vegas and Minneapolis. 5. The World Heath Organisation reports that the health effects witnessed in wildlife species may vary from subtle changes in the physiology and sexual behaviour of species to permanently altered sexual differentiation. 6. It is assumed, however, that since these chemicals are affecting animals, they must be effecting humans too. A number of reproductive health effects in the human population have been observed in which EDCs can play a role. 7. The abovementioned findings lead to the following report of the World Wildlife Foundation: The effect of endocrine disruptors on animals are varied – ranging from alligators born with abnormally small penises and birds with cross beaks, to the sudden disappearance of entire populations. Wildlife researchers over the last few years have unearthed a variety of endocrine disruptor-related effects: • interrupted sexual development; • thyroid system disorders; • inability to breed; • reduced immune response; • abnormal mating and parenting behaviour. Species such as terns, gulls, harbour seals, bald eagles, beluga whales, lake trout, panthers, alligators, turtles, and others, have suffered more than one of these effects.
At present in South Africa, large quantities of EDCs are being released into our atmosphere, soil and groundwater through the manufacture, use and waste disposal of EDC containing products. Of particular concern is the use of highly toxic endocrine disrupting chemicals in their direct form such as DDT.
The presence of EDCs in South African waters systems may have an impact on the health of the South African population and wildlife. In related studies EDC effects have been noticed in animals (fish, birds and eland).
South Africa realised this vast problem, but research only started late. The South African EDC research programme was initiated under the leadership of the Water Research Council (WRC) in 1999. Alarming discoveries were made. A pilot study was conducted in an urban nature reserve in Gauteng lead by Prof Riana Bornman of the University of Pretoria’s Department of Urology. This reserve was selected because it receives effluent from small sewage treatment plants, industries and informal settlements. The water was analysed over a period of two years – and the findings: The study concluded that wildlife in the area is already affected. Wildlife exposure seems to manifest in femination of fish and amphibian species, and on conditions such as intersex (forming of eggs in the testes).
A further WRC funded investigation was done in three drinking plants in Gauteng. The outcome: The bio-assays showed estrogenic activity in source and drinking water, while chemical analysis also indicated the occasional presence of EDCs in water samples.
Table 1 Hormone content at four sites
|1||Nov 2003||Mhakatini flats||56.98||3.73||ND|
|Vaal River Barage||73.2||6.73||ND|
|2||Mar 2004||Mhakatini flats||19.1||423.27||380.0|
|Vaal River Barage||25.78||411.13||321.0|
|3||Jul 2004||Mhakatini flats||15.93||ND||ND|
|Vaal River Barage||65.00||ND||ND|
|Vaal River Barage||43.83||ND||ND|
[i] ng/l = ppt (parts per trillion)
Estrone was detected at all the sited and during all the sampling events. The Estrone content varied quite extensively between sampling points as well as events. The Estrone values found were significantly higher than values reported in water in Europe. We will need to take notice of the warning from Dr Willem Serfontein with reference to hormones. In his book Feel Better, Live Longer he warns against hormone residues in meat, hormone disrupters in soft plastic, insecticides and heavy metals. These substances can cause hormone changes, even in minute quantities. There was an increase in hormone-related illnesses in the past 50 years. In a study which was published in the British Medical Journal in 1992 researchers found a 50% reduction in men’s sperm counts.
Dr. David Carpenter, who directs the Institute for Health and the Environment of the State University of New York at Albany writes: We know we are being exposed to other people’s drugs through our drinking water, and that can’t be good.
Professor Robert Morris, an environmental health consultant from Tufts University writes in August 2004: … treatment systems were all initially designed to get rid of bacteria and viruses. They have filters and use chlorine, but that doesn’t do a whole lot to get rid of chemical contaminants.
The only way to be sure that you and your family don’t ingest any EDCs is to purify your drinking and cooking water. Reverse osmosis is the most advanced and cost effective method of purifying water. Contact Absolutely Pure Water Head Office at 011-907-8377 for more information on reverse osmosis water purifiers and Endocrine Disruptive Chemicals.
BE WISE – DON’T COMPROMISE!
- Serfontein W (2003). Feel Better, Live Longer. Tafelberg Publishers, Cape Town, p.56.
- Internet: Fiona Wellby in CRC for Water Quality and Treatment.
- http://www.nrdc.org: NRDC: Endocrine Disruptors FAQ
- Associated Press Probe Finds Drugs in Drinking Water: www.breitbart.com
- The Straight Dope: www.straightdope.com
- San Diego Earth Times: Drugs in the water: www.sdearthtimes.com
- Pharmaceuticals In Our Water Supplies: http://ag.arizona.edu
- Life Streams International Manufacturing Co. Drugs in Our Drinking Water: www.wholly-water.com
- Endocrine Disrupters: http://whyfiles.org