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Toxic Estrogenic Chemical Sunscreens
Even worse for your health is the fact that many common free radical generating sunscreen chemicals also have estrogen like-effects. Such effects can increase cancers, cause birth defects in children, lower sperm counts and penis size in men, plus a plethora of other medical problems. These effects are similar to many banned chemicals such as DDT, Dioxin, PCBs.
Estrogenic chemicals can mimic hormonal (or real) estrogen, the key female sex hormone. When the body's hormone receptors recognize the estrogenic chemical as estrogen, the result is feminization of the tissue.
Some of these effects may be more subtle than physical abnormalities and may manifest themselves as behavioral changes1, such as aberrant behavior of birds during nesting, which can have significant effects on their nesting success.
Government regulations require that new chemicals pass screening tests to determine that they do not cause cancer. But no rules yet require similar testing of chemicals for effects on reproductive hormones.
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| Estrogenic Toxins | Intended Uses |
| DDT (Dichloro, diphenyl, trichloroethane) | Insecticide, especially for mosquitoes |
| Dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin and similar chemicals) | Chemical by-product during manufacturing of insecticides and plastics |
| PCBs (Polychlorinated Biphenyls) | Insulating oil for electrical transformers |
| 2,4-D | Broadleaf weed killer |
| Diethylstilbestrol (DES) | A potent synthetic estrogen |
| Chemical Sunscreens | Blocking ultraviolet rays on human skin |
Expected Effects of Estrogenic Chemicals in Humans
In Women:
- Endometriosis
- Migraine
- Severe PMS
- Erratic periods
- Increased breast and uterine cancer
- Fibrocystic breast disease
- Uterine cysts
In Men:
- Lowered sperm counts
- Sexual identity confusion
- Breast enlargement
- Smaller than normal penis size
- More testicular cancer
- Undescended testicles
- Block or reduce fetal imprinting of male behavior pattern in brain
Discovery of Gender-Bending Estrogenic Chemicals in the Environment
In the 1950s, the effect of estrogenic toxins such as DDT was linked to eggshell thinning in many bird species. Chemicals with estrogen-like actions can also cause severe developmental problems such as turning fish into hermaphrodites. Over the past 50 years, studies on estrogenic toxins have greatly expanded our knowledge of these effect - some of which is detailed below.
Many hormone affecting chemicals remain in widespread use. 2,4-D, and similar products, are the largest-selling broadleaf herbicides in North America and some 60 million pounds of such chemicals are applied annually in the USA alone. Three widely used pesticides are estrogenic: dieldrin, toxaphene, and endosulfan. While dieldrin and toxaphene have been banned, endosulfan remains the USA's most heavily used pesticide.
Not all environmental gender-benders are estrogenic. Benomyl, a fungicide used on crops such as rice, tomatoes, apples, and grapes, has toxic actions on the testes where it causes the premature release of cells that would have become sperm.
Also, the greatest increases in human cancers over the last 30 years have been those of the breast, ovaries, testes, and prostate, all tissues that are sensitive to sex hormones.
Many Common Sunscreen Chemicals are Strong Estrogens
Margaret Schlumpf and her colleagues (Institute of Pharmacology and Toxicology, University of Zurich, Switzerland) have found that many widely-used sunscreen chemicals mimic the effects of estrogen and trigger developmental abnormalities in rats.
Her group tested six common chemicals that are used in sunscreens, lipsticks and facial cosmetics. Five of the six tested chemicals (benzophenone-3, homosalate, 4-methyl-benzylidene camphor (4-MBC), octyl-methoxycinnamate and octyl-dimethyl-PABA) behaved like strong estrogen in lab tests and caused cancer cells to grow more rapidly.
Uterine Growth and Endometriosis
One very common sunscreen chemical, 4-MBC, was mixed with olive oil and applied to rat skin. This caused a doubling of the rate of uterine growth well before puberty. "That was scary, because we used concentrations that are in the range allowed in sunscreens," said Schlumpf.
Three of the six caused developmental abnormalities in animals. The major cause of sterility in women in the USA is endometriosis, a condition afflicting 5.5% of American women. Exposure to excessive estrogen, that may have come from such sunscreens, is felt to be the primary cause of endometriosis.
Breast Milk
Schlumpf's group also found estrogenic sunscreens in the breast milk of mothers at levels of nanograms per kilogram of fat. This is the about same level as other known environmental contaminants such as PCBs. Schlumpf commented that this exposure could be dramatically increased in childhood by the large amount of sunscreen used by bathers, especially children. Her group is following the offspring of 4-MBC exposed rats to see if they develop health problems.
Based on these results, the Swiss researchers concluded that the impact of sunscreens containing these "endocrine disruptors" should be investigated more closely, in particular their penetration through human skin.
Estrogenic Synergies May Multiply Toxic Effects
Combinations of estrogenic sunscreens and other pollutants may act together to intensify their effects. Researchers at Tulane University in New Orleans believe that a mixture of estrogenic toxins -- such as sunscreens, PCBs, DDT, etc., are more harmful if mixed together. The Tulane researchers found one mixture of estrogenic toxins to be 160 to 1600 times more toxic than the individual chemicals in the mixture.
Gender-Bending Effects are Most Severe During Early Development
Current evidence points to early development (embryo, fetus, juvenile) as the time when children's organs are the most sensitive to estrogen exposure and developmental abnormalities. However, some effects may not become apparent until later in life, when normal sexual maturity is expected.
The basic human form is female. Early in fetal development, the genes must signal if a fetus is to be male. The secretion of male hormones is the signal that activates genes that cause male development. If this does not happen, the human has female imprinting - regardless of whether the person's cells have male (XY) or female genes (XX). If a mother has been exposed to a natural estrogen or estrogenic toxin during the crucial period when genes normally activate masculine patterns, the seventh and 14th weeks of pregnancy, then there is not the proper switching from female to male. If the estrogenic toxins only appear sporadically (such as when the mother uses an estrogenic sunscreen, the disruptions may not trigger a complete reversal of a male's gender, but may exert subtle physical (such a reduced penis size) and mental changes (such as sex role confusion) that become apparent later in life. Conversely, if a synthetic compound blocks estrogen actions, this can produce the sex organs of a male in a fetus that is genetically female.
After using chemical sunscreens, a pregnant woman mother may unwittingly pass some hormone-mimicking pollutants to her child before birth through her placental blood supply and via her breast milk with which she later feeds her newborn.
Some currently used pesticides have been found to interfere with male development, producing undescended testes, nipples on males, hypospadias, decreased sperm counts, and altered mating behavior. When a widely used insecticide, methoxychlor, was fed at low doses to pregnant mice, it caused permanent increases in prostate weight in male offspring of females.
Loss of Libido in Men
Estrogenic chemicals block testosterone actions. This can reduce sexual arousal and sensation and contribute the a loss of libido.
Testicular Cancer
Many industrialized countries have witnessed recently a sharp rise in testicular cancer, according to Dr. Skakkebaek, (Department of Growth and Reproduction at Rigshospitalet, Copenhagen, Denmark). Some of the first data reporting this increase emerged in Denmark, which has maintained a national cancer registry since 1947.
In Denmark, the incidence of testicular cancer has more than tripled over the past 50 years and the rate of increase continues to grow. Similar increases have also been reported in Scotland, the United States, and other Scandinavian countries.
Human Sperm Counts Decline
The sperm count in men in industrialized countries has dropped 50% during the past 50 years, and the exposure to endocrine-disrupting compounds is the most likely cause. Skakoebaek and his group conducted an analysis of previously published studies on semen quality. The international data, from studies involving 14,947 men, indicate that the average density of sperm has fallen from 113 million per milliliter of semen in 1940 to just 66 million per ml in 1990.
Skakkebaek's group also noted that because the volume of semen available in these men at any given time has also dropped an average of 19 percent, the 50-year drop in sperm count has been larger than sperm density alone would indicate.
Undescended Testicles (cryptorchidism)
Though formed near the kidneys, both testicles should migrate down into the scrotum by birth. Undescended testicles usually complete their migration within a year or two after birth, but some never do. Men with undescended testicles are unable to make sperm.
Only a few countries maintain registries on this condition, but Skakkebaek found that two British studies documented a near doubling of the number of boys born with at least one undescended testicle from about 1.6 percent in the 1950s to 2.9 percent in the late 1970s.
Other studies have reported that in England and the USA, cryptorchidism has more than doubled in men during the last four decades.
In young boys living in an area of heavy agricultural activity on the Spanish Mediterranean coast, there was found an association between pesticide exposure and undescended testicles.
Hypospadias in Men
Hypospadias are congenital abnormalities of the urinary tract. During fetal development, the penis possesses an open groove down its length that normally closes before birth. Boys born with only partial closure of the groove need surgery to correct the problem.
Birth registries in England and Wales record that hypospadias more than doubled between 1964 and 1983. Further studies found link between undescended testicles at birth and testicular cancer in adulthood. Low sperm counts or abnormal sperm also are associated with testicular cancer.
All these changes may be the consequence of fetal exposure. Testicular cancer, undescended testicles, hypospadias, and poor-quality semen have been found in the male offspring of women who, during pregnancy, were treated with diethylstilbestrol (DES), a potent synthetic estrogen. Research at the National Institute of Environmental Health Sciences in Research Triangle Park, N.C. found many environmental contaminants can mimic the reproductive effects of estrogen and DES in male animals.
Estrogenic PCBs and Insecticides Diminish Penis Size in Humans and Animals
Boys in Taiwan exposed to PCBs (polychlorinated biphenyls) while in their mothers' womb developed smaller than normal penises as they matured.
The boys in Taiwan are called the "yucheng" (or "oil disease") children. A similar PCB contamination ("yusho") occurred in Japan in 1968. When 115 yucheng children were examined, they were found to be delayed when compared to controls. The delayed development effects in the children's behavior that were most noticeable were the age when they first (1) talked with sentences, (2) turned pages of books, (3) carried out requests of parents, and (4) were able to hold pencils and catch balls.
The boy's mothers had eaten PCB-contaminated rice oil in 1979. The children consumed none of the oil but they were exposed before birth to PCBs in their mother's blood and after birth to PCBs in their mother's milk. The rice oil contained 100 parts per million (ppm) PCBs. A new mother in the USA has an average of one ppm PCBs in her breast milk.
Researchers at University of Wisconsin found low exposures before birth to dioxin, another toxic estrogen, feminized the behavior of male rats during adulthood, and sharply reduced their sperm production. The researchers concluded that the fetal male reproductive system was more sensitive to dioxin than any other organ-system studied."
Feminized Male Alligators
Male alligators exposed to pesticides in Florida have difficulty reproducing, partly because their penises are not developing to normal size. Effects attributed to estrogenic environmental toxins have produced male American alligators with underdeveloped sex organs and vitellogenin (an egg and yolk protein normally found only in females) in male animals.
Also, alligator eggs exposed to DDT or another pesticide, dicofol, hatch male alligators that grow penises only one-third to one-half normal size, and fail to breed.
In addition, males of of many other wildlife species in the same areas of Florida (birds, fish, amphibians, and mammals) are being "feminized" by exposure to low levels of pesticides and other toxic chemicals released into the environment.
Florida Panthers
The Florida panther, an endangered species, is failing to reproduce itself. There are only 30 to 50 panthers remaining, and the reason for the decline has postulated to an effect of environmental estrogens. Between 1985 and 1990, 67 percent of male panthers were born with one or more undescended testicles (cryptorchidism). Some Florida panthers are sterile and many others produce abnormal or deformed sperm.
Santa Barbara's Lesbian Seagulls
Dr. Michael Fry at University of California, Davis, reported that Western gulls on Santa Barbara Island are often in recent years becoming lesbian gulls, with female pairs building nests and trying to hatch eggs and raise offspring. Fry attributes this as partly due to male seagulls' increasing indifference to sex. Examinations found that the male gulls often have feminized sex organs, attributed to the males being "chemically castrated" by DDT and other estrogenic other environmental pollutants.
Orcas of Pacific Northwest Dying from Estrogenic Toxins
Every summer, I spend many happy weekends fishing for salmon off the coast of American Camp National Park on San Juan Island in Washington State. Normally, when we are fishing, we get a visit from the San Juan Orca Pod. Usually Orca just check out the area around the boat for salmon but at times they stop for hours and fish around the boat. The smaller Orca spend a lot of time with their heads out of the water or "spying" to see what happens above water. In the picture, my wife is watching two Orca immediately to the right of her head (but not easy to see in this photo) who were fishing around our boat. The Orca are friendly and very inquisitive.
Every summer, I spend many happy weekends fishing for salmon off the coast of American Camp National Park on San Juan Island in Washington State. Normally, when we are fishing, we get a visit from the San Juan Orca Pod. Usually Orca just check out the area around the boat for salmon but at times they stop for hours and fish around the boat. The smaller Orca spend a lot of time with their heads out of the water or "spying" to see what happens above water. In the picture, my wife is watching two Orca immediately to the right of her head (but not easy to see in this photo) who were fishing around our boat. The Orca are friendly and very inquisitive.
However, the resident Orca pod of Washington State and British Columbia is severely contaminated with organic pollutants like PCBs. The pod has suffered a drastic reduction in numbers in the past 10 years. Scientists have used a light-weight dart system to obtain small samples of skin and blubber from Orcas and these were analyzed for PCBs and other contaminants.
The samples obtained from individually recognizable Orcas that have been the subjects of studies and photo identification since 1973 and were analyzed in relation to sex, age and subpopulation. The Orcas in this region are separated into two groups: the resident Orca that feed primarily upon salmon, and "transient" Orca that feed mainly on other marine mammals. Samples were obtained from 47 individuals: 15 samples from transients and 32 from residents (subdivided into individuals from a northern and a southern pod).
| Group | Males PCB Concentration |
Females PCB Concentration |
| Transient | 251 mg/kg | 59 mg/kg |
| Northern Residents (Mainly British Columbia) |
37 mg/kg | 9 mg/kg |
| Southern Residents (Mainly Washington State) |
146 mg/kg | 55mg/kg |
The concentrations of PCBs in all groups were high, especially in transient males. The sexual differences in contaminants are similar to other whales. Females transfer accumulated PCBs to their offspring, first in the womb and then via lactation. Males have no no way to remove the contaminants.
The greater PCB concentrations observed in 'transients' is a result of dietary differences. By eating other marine mammals, the 'transients' are one level higher in the food chain. They eat predators of salmon who have already accumulated PCBs, in contrast residents eat salmon directly.
Wider Social Effects of Estrogenic Sunscreens 
In countries where sunscreens have been extensively used over the past 50 years, there have also been profound changes in sexual attitudes and conduct. Many scientists are of the opinion that some of these changes have been induced by the widespread exposure to estrogenic chemicals. These effects include sexual confusion, unhappiness, and a difficulty in bonding with others. This is exemplified by falling or negative birth rates in most culturally advanced societies.
The texts from classical Greece and Rome indicate that while the ancients may have been guilty of sexual excesses, trying just about anything that humans could think of, but they seemed to have never suffered the types of sexual insecurity and sexual gender confusion that typifies our current society. Today we think in terms of various types of rigid sexual life styles but the ancients viewed all variants of sexual attraction as aspects of one common theme. It may be that environmental estrogenic toxins (in sunscreens and the wider environment) are altering normal brain development during fetal development and this alters subsequent thought patterns and desires and produces the subsequent confusion.
If you have questions about this assertion, you might read the The Satyricon of Petronius by Gaius Petronius (~27-66 A.D.) who was the emperor Nero's advisor in matters of luxury and extravagance (his unofficial title was arbiter elegantiae). He is recorded to have slept his days and partied nights. A lover of style, manners, and literature, and his personality was characterized by freedom, a lack of self-consciousness, a loose tongue, and was capable of writing the most literate and creative prose in Latin. He focused on satire that could be written about some social arenas written today. An example (non-sexual) is as follows, " We reached the dining room. Boys from Egypt poured cooled water on our hands while others ministered to our feet, removing the hangnails with precision. I began chatting with my neighbor. Who was that woman running here and there? "The host's wife," he replied. "She counts her money by the bushel. But take care you don't scorn the other freedmen here. They're oozing wealth too. See that one reclining at the end of the couch? Today he's worth 800,000. He's newly freed. Not too long ago, he carried wood on his back."
An alternative is to watch Frederico Fellini's film " Satyricon" released in 1969. The film is toned down from the book but you will get the general idea.