Endocrine disruptors Ref. - http://www.nrdc.org/health/effects/qendoc.asp
1. What is the endocrine system?
The endocrine system is a complex network of glands and hormones that regulates many of the body's functions, including growth, development and maturation, as well as the way various organs operate. The endocrine glands -- including the pituitary, thyroid, adrenal, thymus, pancreas, ovaries, and testes -- release carefully-measured amounts of hormones into the bloodstream that act as natural chemical messengers, traveling to different parts of the body in order to control and adjust many life functions.
2. What is an endocrine disruptor?
An endocrine disruptor is a synthetic chemical that when absorbed into the body either mimics or blocks hormones and disrupts the body's normal functions. This disruption can happen through altering normal hormone levels, halting or stimulating the production of hormones, or changing the way hormones travel through the body, thus affecting the functions that these hormones control. Chemicals that are known human endocrine disruptors include diethylstilbestrol (the drug DES), dioxin, PCBs, DDT, and some other pesticides. Many chemicals, particularly pesticides and plasticizers, are suspected endocrine disruptors based on limited animal studies.
3. What are some likely routes of exposure to endocrine disruptors?
Exposure to endocrine disruptors can occur through direct contact with pesticides and other chemicals or through ingestion of contaminated water, food, or air. Chemicals suspected of acting as endocrine disruptors are found in insecticides, herbicides, fumigants and fungicides that are used in agriculture as well as in the home. Industrial workers can be exposed to chemicals such as detergents, resins, and plasticizers with endocrine disrupting properties. Endocrine disruptors enter the air or water as a byproduct of many chemical and manufacturing processes and when plastics and other materials are burned. Further, studies have found that endocrine disruptors can leach out of plastics, including the type of plastic used to make hospital intravenous bags. Many endocrine disruptors are persistent in the environment and accumulate in fat, so the greatest exposures come from eating fatty foods and fish from contaminated water.
4. How do we know that endocrine disruptors are dangerous?
Many plant and animal species are showing signs of ill health due to exposure to endocrine disrupting chemicals. For example, fish in the Great Lakes, which are contaminated with polychlorinated biphenyls (PCBs) and other man-made chemicals, have numerous reproductive problems as well as abnormal swelling of the thyroid glands. Fish-eating birds in the Great Lakes area, such as eagles, terns, and gulls, have shown similar dysfunctions.
Scientists have also pointed to endocrine disruptors as the cause of a declining alligator population in Lake Apopka, Florida. The alligators in this area have diminished reproductive organs that prevent successful reproduction. These problems were connected to a large pesticide spill several years earlier, and the alligators were found to have endocrine disrupting chemicals in their bodies and eggs.
5. Should humans be concerned for their health based on evidence that fish, birds and alligators have been affected?
Yes. All vertebrates (fish, amphibians, reptiles, birds, and mammals, including humans) are fundamentally similar during early embryonic development. Scientists can therefore use the evidence acquired on other species to make predictions about endocrine disrupting effects on humans.
6. Is there direct evidence that humans are susceptible to endocrine disruption?
Yes. In the 1950s and 1960s pregnant women were prescribed diethylstilbestrol (DES), a synthetic estrogen, to prevent miscarriages. Not only did DES fail to prevent miscarriages, but it also caused health problems for many of these women's children. In 1971, doctors began reporting high rates of unusual vaginal cancers in teenage girls. Investigations of the girls' environmental exposures traced the problem to their mothers' use of DES. The girls also suffered birth defects of the uterus and ovaries, and immune system suppression.
7. Are children at greater risk from endocrine disruptor exposure?
Yes. Because endocrine disruptors affect the development of the body's vital organs and hormonal systems, infants, children and developing fetuses are more vulnerable to exposure. And as was the case with DES, parents' exposure to certain chemicals may produce unexpected -- and tragic -- effects in their children, even decades later.
8. These days don't chemicals have to be safe to be allowed on the market?
No. The majority of the more than 2,000 chemicals that come onto the market every year do not go through even the simplest tests to determine toxicity. Even when some tests are carried out, they do not assess whether or not a chemical has endocrine interfering properties.
9. What can I do to reduce my risk of exposure?
* Educate yourself about endocrine disruptors, and educate your family and friends.
* Buy organic food whenever possible.
* Avoid using pesticides in your home or yard, or on your pet -- use baits or traps instead, keeping your home especially clean to prevent ant or roach infestations.
* Find out if pesticides are used in your child's school or day care center and campaign for non-toxic alternatives.
* Avoid fatty foods such as cheese and meat whenever possible.
* If you eat fish from lakes, rivers, or bays, check with your state to see if they are contaminated.
* Avoid heating food in plastic containers, or storing fatty foods in plastic containers or plastic wrap.
* Do not give young children soft plastic teethers or toys, since these leach potential endocrine disrupting chemicals.
* Support efforts to get strong government regulation of and increased research on endocrine disrupting chemicals.
News Article - Evidence of poison
http://www.mg.co.za/articlePage.aspx?articleid=301375&area=/insight/insight__national/
Fiona Macleod
08 March 2007 11:59
A Limpopo medical doctor has documented a string of physical abnormalities -- including breasts on a five-year-old girl -- that he believes are directly linked to the unregulated use of agricultural chemicals.
Dr Johan Minnaar (44) has produced evidence of serious illnesses and disorders among his patients in Groblersdal, where commercial farmers are spraying large amounts of pesticides on crops.
Horrific cases include teenage boys temporarily “growing breasts” during spraying seasons, miscarriages, partial facial paralysis, cancers and ear malfunctions. Many of his patients suffer from milder poisoning symptoms, such as asthma, sinusitis, headaches, dizziness and depression.
Minnaar, who has been practicing as a doctor in Groblersdal since 1997, took the unusual step of coming forward with his evidence after unsuccessful attempts to get government and regulatory authorities to intervene.
He said: “Groblersdal is surrounded by farms growing mostly citrus and grapes, but also cotton, vegetables and maize. Throughout the year there is constant crop spraying with pesticides containing organophosphate's and carbonates. No one has informed the community what pesticides are being used, even though the law states people must be notified before spraying.”
Minnaar started investigating after realizing that symptoms he had experienced over six years followed a pattern.
“I experienced chronic fatigue, nausea, muscle aches and pains, skin rashes and arthritis, particularly from August till November, when there is a noticeable increase in the spraying. On investigation, it became clear that other people had these symptoms at the same time.”
Last August, he became so ill that he had to stay at home for two weeks. His wife and three children also showed symptoms. He began regularly testing his and his spouse’s blood and the tests showed they were exposed to organophosphate's and carbonate pesticides.
Minnaar laid complaints with the registrar of the national agriculture department, the water affairs department and the labour and health departments of the Limpopo government. He also tackled the farmers, chemical companies and crop sprayers.
The spraying continued and, on two days in February this year, large amounts of carbamate were released during the aerial spraying of citrus orchards. Residents were not warned beforehand. Among those who later showed signs of poisoning were pupils of two schools located in the orchards.
Minnaar said pupils regularly played on the sports fields during spraying. The teenage boys who had consulted him about “growing breasts” in the spraying seasons attended the schools.
In late January, a woman brought a five-year-old girl who had developed breasts to his consulting rooms. Minnaar suspected it could be linked to poisoning and referred her case to Limpopo government officials, who he met two days later.
“As with many patients, she had no access to medical facilities or funds. The authorities undertook to get her medical testing and treatment, but we’ve heard nothing,” he said.
According to Professor Leslie London of the University of Cape Town’s health sciences faculty, premature puberty and other hormonal abnormalities are symptoms of contamination by pesticides containing “endocrine disruptors”.
A 2005 study of girls in Mexican farming areas, titled Altered Breast Development in Girls, indicated that pesticides could affect breast development and lead to early puberty.
Said London: “It has been shown that endocrine disruptors can also affect sexual maturation and differentiation. A study in Sri Lanka of a pesticide called endosulfan found that boys living in villages below cashew nut plantations sprayed with endosulfan had impaired sexual maturity and other reproductive impairments.”
London researched aerial crop spraying around Groblersdal in 2005, with a focus on risks to small farmers rather than health impacts. Last year, he published research on possible links between aerial organophosphate spraying in the Northern Cape and Guillain-Barré Syndrome, a neurological disorder.
“The problem of rural towns affected by agricultural application of pesticides is ubiquitous,” he said. “Present regulatory and safety management methods really don’t address this problem sufficiently.
“I think there is a view that if you choose to live in the country, you should accept this as a way of life. That is a societal value decision, not a matter of science.”
The health department’s directorate of environmental health has announced plans to launch a chemical safety programme in Groblersdal at the end of March. According to its draft concept document, “the aim is to launch the programme to inform provinces that national [government] is willing to assist them in the management of chemicals”.
The draft programme identifies schoolchildren, women, farmers and farmworkers, shack dwellers, informal traders and manufacturers as the “most vulnerable communities in municipalities that lack capacity to properly and satisfactorily deal with chemical safety issues”.
South Africa is a signatory to international conventions aimed at promoting chemical safety, and the labour ministry said in October that chemical safety was “high on the minister’s agenda”. But crop spraying is a highly technical industry, and pinpointing contamination is difficult.
London said it was almost impossible for applicators in planes to control the drift of chemical sprays. “Aerial application has been shown in some studies to drift more than 2km, even in the absence of strong winds.”
European countries strictly regulate the industry through buffer zones around residential areas and warning systems, he added.
Gerrit van Vuuren, an aerial application consultant at Croplife South Africa, blamed mist-spraying of crops on the ground. “It is absolutely wrong to conclude that because there is a yellow aircraft spraying agrichemicals in an area, it must the reason for ill health effects,” he said.
Van Vuuren said mist-blowers apply more than 1 000 liters of spray mixture a hectare, compared to 30 to 40 liters in the case of aerial spraying. They also blow a significant volume of the spray higher than 6m into the air.
“A couple of mist-blowers spraying thousands of liters of spray mixtures at night are less visible than an aircraft spraying a couple of hundred liters in the morning.”
He said it was up to farmers to notify inhabitants and issue warnings. They were also supposed to ensure no one entered their fields during spraying.
The environmental health unit at the Elias Motsoaledi municipality, under which Groblersdal falls, said it was “busy investigating the usage of pesticides being sprayed from aero planes, as nuisances do occur from these activities”.
But Minnaar is frustrated by government promises to investigate. “For all practical purposes, the supposed controls are not working. While they keep promising to sort it out, we are getting poisoned,” he said.
