Boys in Taiwan exposed to PCBs while in their mothers' womb develop smaller penises as they mature, compared to normal boys in Taiwan.
The boys in Taiwan were born to mothers who unwittingly consumed PCB-contaminated rice oil during a 10-month period in 1979. As many as 2000 people consumed the contaminated oil. The children consumed no contaminated oil themselves; they were exposed before birth to PCBs that were carried by their mothers' blood and crossed the placenta; they may have also been exposed shortly after birth by drinking their mothers' milk. The rice oil contained 100 parts per million (ppm) PCBs and 0.1 ppm PCDFs [polychlorinated dibenzofurans, a potent dioxin-like poison].
The information from Taiwan about male genital development tends to confirm that PCB exposure in the womb has effects different from, and more powerful than, those caused by PCB exposure in later life. The same seems to be true in wildlife as well.
Alligator eggs exposed to DDT or a related pesticide, dicophol, produce male alligators with abnormal sex hormones (estrogen and testosterone) in their blood, leading to growth of penises one-third to one-half normal size, and subsequent reproductive failure.
The Florida panther, an
endangered species, is also failing
to reproduce itself. There are only 30 to 50 panthers
and the reason for the decline has been a mystery. Now
have reported that between 1985 and 1990, 67 percent of male
were born with one or more undescended testicles, a condition known as
cryptorchidism. In England and the U.S., cryptorchidism has
than doubled in men during the last four decades.
Florida panthers are sterile and others produce abnormal or deformed
It was reported last year that sperm count in men in industrialized
has dropped 50% during the past 50 years.
Children are maturing much earlier
One in six girls show early signs of puberty by the time they are eight-years-old, researchers have found.
This compares to one in 100 girls a generation ago, the Observer newspaper reported.
The research carried out at Bristol University's Institute of Child Health tracked the development of 14,000 children from birth as part of their "Children of the Nineties" study.
It also found that one in 14 eight-year-old boys had pubic hair, an early indicator of puberty, compared with one in 150 boys of their father's generation.
The research showed that, from a sample of 630 girls, one in six had started to show early signs of puberty by the time they were eight.
It was the first study into puberty to take place in Britain since 1969.
A study in the early 1990s gave an average of between 12 and 13 years.
Boys, Like Girls, May Be Starting Puberty Earlier
A new study suggests that boys in the United States, like girls, are entering puberty slightly earlier than previously thought, with blacks the most likely to develop the first signs by age 10.
Early puberty may increase a boy's chances of developing testicular cancer later in life because it may mean longer exposure to sex hormones, said University of North Carolina researcher Marcia Herman-Giddens, the study's lead author. If boys are truly maturing earlier, then sex education classes should begin earlier, she said.
The study - an analysis of a 1988-94 federally funded national health survey - found the average age for developing pubic hair was 12 in white boys, 11.2 years in blacks and 12.3 years for Mexican-Americans. That's up to half a year earlier than in earlier studies, Herman-Giddens said.
Premature puberty link to DDT
DDT is still used in countries like India Scientists believe the controversial pesticide DDT is responsible for premature puberty in girls in developing countries.
Researchers in Belgium, who carried out the study, found children who had emigrated from countries such as India and Colombia were 80 times more likely to start puberty unusually young.
Three-quarters of these immigrant children with "precocious" puberty had high levels of a chemical derivative of DDT in their blood.
This chemical, DDE, mimics the effects of the oestrogen hormone, which plays an important role in controlling sexual development.
The girls in the Belgian study began developing breasts before the age of eight, and started their periods before they were 10.
The team, led by Jean -Pierre Bourguignon from the University of Liege, discovered that children emigrating to other European countries also had an increased tendency to begin puberty early.
They did not believe this could be entirely attributed to a better diet.
The team tested the children for a range of
pesticides and found
that 21 out of 26 immigrant children with precocious puberty had high
of DDE in their blood.
David Buffin from the Pesticide Action Network said: "We have known for a while, the chronic problems associated with DDT.
"And we have been concerned about its chronic effects in terms of cancer and its effect on reproduction.
"It's a known carcinogen and is suspected to disrupt the endocrine system."
Friends of the Earth (FoE) is equally worried that DDT used in foreign countries is entering the food chain closer to home with the increase in imported food.
FoE's food campaigner Sandra Bell said: "This certainly seems to add to the weight of growing evidence that hormone disrupting pesticides could be having a very serious long term effect on our health and adds to our demand that we should be banning all hormone disrupting pesticides which are turning up in our food."
DDT has been banned in the European Union (EU) and US for decades, but is still used in many developing countries, mainly to control malaria.
A three year study in the US, 20 years ago, found that the children of pregnant mothers whose blood and breast milk contained high levels of DDT, reached sexual maturity earlier.
Scientists monitored the physical growth and maturity of 600 offspring from these women and discovered girls with the highest pre-natal exposures to DDT and another hormone altering chemicals entered puberty 11 months earlier than girls with lower exposure.
The mouse study should "serve as a guide for human research"
US scientists claim to have found evidence that some of the reproductive and weight problems seen in western societies in recent years may be the result of exposure to a chemical used to make everyday plastics.
The researchers exposed unborn mice to bisphenol A (BPA) which is employed in the manufacture of polycarbonate plastic products such as baby bottles, tin can linings, some toys and certain types of food storage containers.
The chemical leaches out of the plastic at a rate that increases with use. In the human body, it can mimic the effects of the sex hormone oestrogen. It is one of a number of so-called endocrine disrupters that can upset the hormonal system and are causing concern among environmentalists.
The team of scientists from the University of Missouri-Columbia and North Carolina State University say the mice experienced premature puberty and an increase in body weight shortly after birth.
In their experiments the researchers used quantities of BPA typical of the levels to which humans are routinely exposed. The mice were exposed only during pregnancy, not after birth. The exposed mice weighed 20% more than normal when examined at puberty.
The conclusion of the researchers is that BPA somehow programs post-natal growth.
"We found that the largest effects happened to the babies of the pregnant mother," says Kembra Howdeshell, one of the lead researchers.
"The chemical did not affect the mother, but
instead it altered the
babies' growth patterns and accelerated timing of sexual maturity.
The team, who have reported their work in the journal Nature, are now calling for more human research.
"We're not offering an answer concerning effects in humans with these findings; instead, the findings pose a question regarding human health," says co-researcher Professor Frederick vom Saal.
"This study should serve as a guide for human research.
"We believe that the medical community should take a long look at this study and consider looking at BPA as a possible cause for the changes in growth, sexual maturation and reproductive abnormalities that have been reported in the humans."
In both humans and animals, the team says there is significant variability in responsiveness to environmental estrogens, and that one source of this variability may be the amount of sex hormones to which the foetus is exposed.
Severe pollution has caused a dramatic rise in male infertility in Shanghai, a new study published in the Shanghai Daily has found.
The study, by the Shanghai Family Planning Research Institute, found that sperm counts among men in the city have dropped 12% since 1987.
In a survey of 1,000 donors at the city's main sperm bank last year, only 20% had a sperm count that was highly fertile, the Shanghai Sperm Bank said. Health officials have blamed pesticides which contaminate vegetables and other foods as well as higher stress levels, the paper reported.
The Shanghai survey follows a report last month in the China Daily newspaper, which claimed between 20% and 30% of Chinese men now suffer from some form of sexual dysfunction, including infertility and impotence.
Fertility problems are said to affect about 15% of all married couples, and of these cases, are third are down to the male partner.
Experts from the East China University of Science and Technology have pointed to a toxin found in pesticides and laundry detergents for the problem.
The toxin, called an "environmental hormone", is linked to impotency and premature puberty in both sexes, the experts told the paper. The hormone disrupts the endocrine system, upsetting the balance of the body's natural hormone levels, the experts said.
"Domestic pollution, including the use of
plastic containers and
chemical additives in foods, has
About 1% of children in Shanghai reach puberty early.
Rapid economic growth in recent years in the country has been followed with a sharp increase in all types of pollution.
A survey of 46 major Chinese cities found only eight meet government standards for water and air pollution.
Many rivers are also said to be dying and about
a third of the country
suffers from acid rain.
|Endocrine disrupters may cause reproductive
and developmental problems.
Alligators living in Florida's Lake Apopka were exposed to the estrogenic pollutants dicofol, DDT and its metabolites, DDD, DDE and chloro-DDT, when a nearby chemical plant had an extensive spill in 1980. Ten years later, researchers trying to find out why alligator populations were dropping in the Lake, found higher than normal mortality among eggs and newborn alligators. They also found that adolescent females had severe ovarian abnormalities and had blood estrogen levels two times higher than normal. The male juvenile alligators were feminized, that is, they had smaller than normal penises, had abnormal testes and had higher estrogen levels and lower testosterone levels in their blood than normal males of the same age. The researchers concluded that chemicals from the spill not only killed developing eggs outright but also altered the embryo's endocrine system (hormone levels and sexual development), which severely limited the alligator's ability to reproduce.
Daughters of mothers who took the synthetic estrogen DES (diethylstilbestrol) during pregnancy to prevent miscarriage have higher rates of reproductive problems, reproductive cancer (vagina, cervix) and malformed reproductive organs (uterus, cervix). Sons may also face higher rates of malformed or small penises, undescended testicles and abnormal sperm. However, a recent study found no evidence of reduced fertility in DES sons.
DES is not only a potent estrogen, similar in strength to the natural estrogen estradiol, but it also has the unique ability to concentrate in target tissues, such as the reproductive tracts of birds, reptiles and other animals, during development and cause abnormalities. This drug serves as an example of what potent estrogenic compounds can do and may illustrate the health effects that other environmental estrogens can produce.
Many studies find that sperm counts in men are falling worldwide, that rates of testicular cancer are increasing and that environmental estrogens may be responsible for these trends
Fetuses and embryos, whose growth and development are highly controlled by the endocrine system, seem especially vulnerable to exposure, as detailed in the previous examples. Mothers can pass contaminants to their offspring prenatally in eggs (amphibians, reptiles, birds) or the womb (mammals) and after birth by breastfeeding newborns. So, even though adult animals exposed to contaminants may not show any ill effects, their offspring may have lifelong health and reproductive abnormalities including reduced fertility, altered sexual behavior, lowered immunity and even cancer.
Studies looking at mammals, reptiles, birds and fish, as well as laboratory studies using rodents, primates and cultured cells, have linked exposure of a developing embryo to environmental contaminants with many permanent health effects in the adult. These effects include:
altered sexual behavior
modified immune system
masculinization of females;
feminization of males (reduced testicles and penis size);
cancers of the female and male reproductive tract;
malformed Fallopian tubes, uterus and cervix
altered bone density and structure.
Atrazine, the top selling weed killer in the United States, disrupts the sexual development of frogs at concentrations 30 times lower than levels allowed by the U.S. Environmental Protection Agency. The researchers who uncovered the problem join environmentalists in expressing concern about heavy use of the herbicide on corn, soybeans and other crops in the U.S. Midwest and around the world.
University of California at Berkeley developmental endocrinologist Tyrone Hayes and his colleagues report that exposing male tadpoles to atrazine in the laboratory, using levels often found in the environment, demasculinizes the tadpoles, preventing male characteristics from fully forming. The atrazine exposure turns the tadpoles into hermaphrodites - creatures with both male and female sexual characteristics.
The herbicide also lowers levels of the male hormone testosterone in sexually mature male frogs by a factor of 10, to levels lower than those found in normal female frogs.
As Hayes later discovered, many atrazine contaminated ponds in the Midwest contain native leopard frogs with the same abnormalities.
"Atrazine exposed frogs don't have normal reproductive systems," Hayes said. "The males have ovaries in their testes and much smaller vocal organs," which are essential in calling potential mates.
In an article in today's issue of the "Proceedings of the National Academy of Sciences," Hayes and his colleagues note that it is unclear whether these abnormalities lead to reduced fertility. Hayes now is trying to determine how the abnormalities affect the frogs' ability to produce offspring.
"The use of atrazine in the environment is basically an uncontrolled experiment - there seems to be no atrazine free environment," Hayes said. "Because it is so widespread, aquatic environments are at risk."
More than 60 million pounds of atrazine were applied last year in the United States alone. Manufacturer Syngenta estimates that farmers use the herbicide to control weeds on about two-thirds of all U.S. farm acres planted with corn and sorghum. On average, atrazine improves corn yield by just over four percent.
Aquatic species, however, swim and breed in atrazine contaminated field runoff. Though previous studies showed deformities and abnormalities in adult amphibians only at very high doses, no one had looked in detail at hormone levels in frogs or at effects on tadpoles, the larval stage of frogs.
The findings come at a time when the Environmental Protection Agency (EPA) is reevaluating allowable levels of atrazine in drinking water, which stand today at three parts per billion (ppb). The EPA has drafted new criteria for the protection of aquatic life, limiting four day average exposures to 12 ppb.
Hayes found hermaphroditism in frogs at exposure levels as low as 0.1 ppb. Levels of 40 ppb of atrazine have been measured in rain and spring water in parts of the Midwest, while atrazine in agricultural runoff can be present at several parts per million.
The herbicide also contaminates drinking water supplies in many communities in the Midwest, leading some environmental groups to voice concern about its effect on children, infants and the developing fetus. France, Germany, Italy, Sweden and Norway are among the nations that have already banned the use of atrazine.
Though Hayes initially received funds from Syngenta for the studies, all the current published studies were conducted independent of Syngenta.
For his laboratory tests, Hayes used the African clawed frog, Xenopus laevis, a popular research subject that, like many frogs, is very sensitive to hormones that mimic the effect of their own sex hormones. If raised in a pond with estrogen, for example, all Xenopus tadpoles turn into females. In the presence of androgens, frogs grow larger voice boxes, or larynges.
In laboratory experiments at various concentrations of atrazine, the researchers found that exposure to the chemical affected the sexual development of frogs at concentrations of 0.1 ppb and higher. That is 30 times lower than the EPA's allowable limit of three ppb in drinking water and 120 times lower than the proposed chronic exposure limit for aquatic life, 12 ppb.
At these concentrations, as many as 16 percent of the animals had more than the normal numbers of gonads - including one animal with six testes - or had both male and female organs: testes and ovaries. None of the control animals, which were not exposed to atrazine, had such abnormalities.
"The current data raise new concerns for amphibians with regard to atrazine," the researchers wrote in their paper. "If such effects occur in the wild, exposed animals would suffer impaired reproductive function."
Atrazine has been in use for 40 years in some 80 countries around the globe. The authors of the report note that the herbicide's effect on sexual development in male frogs could be one of many factors in the global decline of amphibians, he added.
"This is very important and elegant work," said Theo Colborn, PhD, a senior scientist at the World Wildlife Fund and an internationally recognized expert on endocrine disrupting chemicals. "Tyrone's work demonstrates the need to do research on the safety of chemicals in the field where the animals live and at the levels to which they are exposed."
"The changes he found in the gonads were not discovered with the traditional high dose atrazine experiments used in the past," Colborn explained. "In addition, microscopic examination of the internal organs of the frogs is required to detect the hidden effects from low dose exposure."
To date, atrazine's effects on mammals and amphibians have been tested only at large doses, not at doses commonly found in the environment.
"The effective doses in the current study," Hayes and his colleagues write, "demonstrate the sensitivity of amphibians relative to other taxa, validate the use of amphibians as sensitive environmental monitors/sentinels, and raise real concern for amphibians in the wild."
But the effects of atrazine on frogs could be a sign that the herbicide is subtly affecting human sex hormones, Hayes said, interfering with androgens such as testosterone, which control male sex characteristics.
"Atrazine is obviously affecting frogs," Hayes said. "We have shown serious effects on their sexual development. We need to ask the questions, 'What are the environmental costs of using atrazine? What diversity have we lost?'"
Recent findings by the U.S. Geological Survey document that atrazine is found in U.S. surface waters, fog and rainwater. Millions of Americans drink tap water laced with atrazine, which is at peak levels in the spring, when corn farmers apply tens of millions of pounds of the chemical on their fields.
"This rigorous scientific study reinforces what we and other scientists have been saying for years: atrazine is a dangerous pesticide," said Dr. Jennifer Sass, a senior scientist at the Natural Resources Defense Council (NRDC), one of several conservation groups that have called for a U.S. ban on atrazine. "The fact that doses of atrazine - at a fraction of the federal tap water standard - disrupted frog reproductive organ development has frightening implications for humans, especially pre-pubescent children."
The NRDC argues that farmers have access to affordable, safer alternatives to atrazine.
"Farmers have found
that modern cultivation practices
allow them to slash the amount of pesticides they apply to their fields
- or dispense with them altogether - without cutting production," said
Jon Devine, an NRDC senior attorney. For example, Devine said, Iowa
discovered they can plant their corn crops in elevated ridges and
weeds mechanically, increasing their profits and eliminating the need
Member of the European Commission, responsible for Environment
"Introduction to debate on Chemicals and Children"
Green Week 2002
Brussels, 16 April 2002
Ladies and Gentlemen,
The fact that the number of frogs has drastically diminishing all over the world has for a long time been a cause of alarm to scientists. But, they have not been able to provide a clear reason for this.
However, in an article in the recent issue of PNAS, the American Academy of Science publication, researchers report that low dozes of atrazine, which is one of the most commonly used herbicides, make male frogs more feminine. They develop lower testosterone doses and the bags that they blow up when they croak (possibly to impress on potential girl friends!) become much smaller. Atrazine also affects the frogs' reproduction capacity. In a test, frog larvae were exposed to this chemical and some of the adults male became two-gendered. Interesting enough, the researchers also notice that the reduction level of frogs is substantially lower in countries where atrazine is forbidden.
This is a scary example from the animal world how chemicals affect the ecological balance. What then about human beings? This, of course, is the subject of a number of discussions here at Green Week.
This morning endocrine disrupters were in the spotlight. In Denmark today 5 % of all children are now born after assisted reproduction. Professor Skakkebaek from Denmark and his research team are of the opinion that environmental factors influence pregnant women carrying male foetuses, who eventually will show poor semen quality and develop testis cancer. What is even more alarming is that we will not see the full scale of the problems until 30-40 years from now when yet unborn boys may wish to reproduce themselves.
Special thanks go to Mark Danzon from the WHO and Domingo Beltran of the EEA who at the inaugural session yesterday launched their joint publication "Children's health and environment: A review of evidence". This report will undoubtedly be a standard reference work and point of departure on what we know and do not know and as a consequence on where we need to focus research attention. for having provided us with such an excellent platform for discussion not only here this week but for years to come when we all will be much more focussing on children's environment and health.
We are today focussing on chemicals, but there are of course, and tragically, other environmental factors that affect children's health. With all these experts around and the most recent scientific results available, it would be presumptuous of me to providing you here today with data. But, let me at least repeat some of the facts that have made a very strong impact on me, and lead me to draw the conclusion that something more and concrete needs to be done:
The Commission's White Paper on a new chemicals strategy outlines two major objectives; first and foremost to safeguard a healthy environment and eliminate threats to public health, but also to ensure the internal market and stimulate innovation and competitiveness in the European chemical industry. The one does by no means exclude the other.
Both Council and the Parliament have come with their opinions, and we are now preparing new legislation. The Commission will present a proposal later this year, and following regular co-decision procedure the new legislation will enter into force in 2004.
Why then do we need a new system? For many reasons, but mainly to overcome the unacceptable present information gap. The present regime differentiates between products that have been placed on the market before and after 1981. The former, i.e. "old" chemicals are not subject to rigorous control and can continuously be used without testing, whereas new ones have to undergo an extremely demanding process which is much too slow.
Worth pointing out is also that the "burden of proof" whether a substance is hazardous or not now fall on the public authority. Consequently, as long as a substance has not undergone the heavy risk assessment procedure and been deemed as explicitly hazardous and forbidden to use, it is OK to market it.
The result is that we today have between 30,000 and 70,000 existing substances on the market, the majority of which (actually 99.1 % of the total market value) we do not know that much about. Worth pointing out is that of the new substances that are tested as many as 70 % are deemed as dangerous!
This is huge lack of information is of course totally unacceptable. In what other industry sector are the majority of the products marketed and used without the most basic information available about their inherent dangers?
This we want to change. Consequently, the revised system will put the responsibility for generating and assessing data on the industry. This will be done step-wise. We propose a registration for all chemicals with only limited information (and the only step) for 80 % of the chemicals. More rigorous evaluation will apply to chemicals used in high volumes or chemicals of great concern some 15 % of the market.
I am convinced that industry indeed can come up with the basic information that we request for the 80 % of the products and this at reasonable costs. Our own estimates indicate a testing cost of 2.1 billion Euro for the industry over 11 years phasing in the "existing" substances. This corresponds to only 0.05 % of the yearly turnover for the chemical industry!
A new chemicals strategy is thus a centrepiece in our efforts of reducing environmental causes to public health in general and children's health in particular.
Launching a new chemicals strategy is also one of the most important decisions the Commission has taken in the context of sustainable development. The step-by-step approach to phase out and substitute the most dangerous substances is crucial for future generations.
I take the opportunity of bringing this up because we notice a campaign from industry in some MS alleging that the Commission proposal will put an end to European chemical innovation, limit the competitiveness and lead to job losses. I can reassure you that these allegations are not founded at all.
On the contrary, making sure that we provide the basic facts about the substance hazards and making this information available will create a demand by consumers and downstream users for "safer" products, and foster innovation of substitutes to dangerous substances. The winner of market shares in the future will be the one who can supply safe products that is the case for all kinds of products we are trading with, including chemicals.
It is important that we get the facts and correct conditions on the table both about the risks in continuing with the "old" system and the opportunities provided in our "new" chemicals strategy.
With this perspective in mind, I very much look forward to listening to the panel discussion on children and chemicals.
Thank you for your attention.
were target compounds for
National Reconnaissance of Emerging Contaminants in US Streams
Paroxetine (antidepressant, antianxiety)
Dehydronifedipine (antianginal metabolite)
Digoxigenin (digoxin metabolite)
Ibuprofen (anti-inflammatory, analgesic)
1,7-Dimethylxanthine (caffeine metabolite)
Cotinine (nicotine metabolite)
Octylphenol monoethoxylate (OPEO1)
Octylphenol diethoxylate (OPEO2)
p-Cresol (wood preservative)
Phthalic anhydride (used in plastics)
Bisphenol A (used in polymers)
Triclosan (antimicrobial disinfectant)
19-Norethisterone (ovulation inhibitor)
Equilenin (hormone replacement therapy)
Equilin (hormone replacement therapy)
Stigmastanol (plant sterol)
DO PICIA W OCENIE
"Woda to produkt najbardziej masowy i najmniej
Z. Hałat, szmaragdowa książeczka "WODA DLA CIEBIE", Warszawa 2000
naukowe dowodzą bezspornie,
że zanieczyszczona woda
jest przyczyną nieprawidłowego rozwoju i zaburzeń czynności ciała,
wywołuje ciężkie choroby, skraca życie ludzi, zwierząt i roślin
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