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From the Townsend Letter
August / September 2012

The False Promises of Sunscreens: The Real Consequences of Their Use Part 2
by Elizabeth Plourde, CLS, NCMP, PhD  

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Part 1 is also online.

Note: In Part 1 of this article, in our July 2012 print magazine, there was an error in the e-mail address for Dr. Plourde. The correct address is

Could This Be One of the Factors Creating the Explosion of Autism and ADHD?
It is critical to research whether sunscreen chemicals, as well as sunscreen use resulting in lower vitamin D levels in mothers and children, could be part of the many environmental factors responsible for the rapid increase in the numbers of children with autism and ADHD in the last several decades. In the US, according to the Centers for Disease Control (CDC), autism spectrum disorder is being diagnosed at younger ages. Their findings reveal that the prevalence in 8-year-old children increased an average of 57% just between the years 2002 and 2006.28

Hormonally, many of the sunscreen chemicals act as potent antitestosterones, which means that the fetal development of boys would experience a much greater impact. The gender difference in autism incidence in the US today shows a ratio of 4 boys for every 1 girl diagnosed.29 More whites use sunscreens, since they do not have the protective melanin in their skin, and a higher percentage do show sunscreen chemicals in their blood compared with those with darker skin. Therefore we would expect to see more autism in the white population, and that is exactly what the statistics reveal – the incidence of autism is in fact higher.30 Additionally, sunscreen chemicals have been identified as thyroid disrupting chemicals (TDC).31 TDCs can create a disruption of the proper signaling of thyroid hormones in the brain during crucial times of cell migration and establishment of neuronal networks, creating permanent alterations in the developing human brain that could result in deficits in mental development.32Research is also revealing that prenatal exposure to thyroid toxic chemicals could be one of the reasons for the current surge in numbers of autistic children.33

Adding pieces of this puzzle together is the research of Dr. George Bartzokis, professor of psychiatry at UCLA's David Geffen School of Medicine. Bartzokis has been researching the role of the myelin sheath in neuropsychiatric disorders such as schizophrenia and Alzheimer's disease. More recently he has extended the idea that autism could be arising because of defective development of the myelin sheath in the nerve fibers in the brain during infant and childhood development. He reasons that toxins combined with genetic vulnerabilities could result in any of the ADHD and autistic spectrum of disorders. Which disorder develops would depend on the stage of brain development that was occurring in the child at the time of exposure to the insult to the myelination process, which heavily depends on cholesterol and nutrients such as vitamin D.34

Another theory being developed by MIT researcher Dr. Stephanie Seneff, along with others, is that autism is in part caused by a severe deficiency in sulfate throughout the body.35 They propose that this deficiency comes about in part due to inadequate sun exposure to the skin, because the synthesis of vitamin D3 sulfate and cholesterol sulfate in the skin depends upon sun exposure. Sunscreen likely interferes with this natural process. Seneff has also argued that both cholesterol and vitamin D have to be available in sufficient quantities for the signaling of the necessary apoptotic pruning to occur in a child's brain, which usually takes place around age 2. This represents removal of irrelevant connections and unproductive neurons during the first years of development, which need to be systematically weeded out as they are no longer useful.36 This weeding does not occur unless there are adequate levels of cholesterol and vitamin D. Such weeding out is essential, and researchers are finding that this process does not occur in autistic children.37

A third possibility for sunscreens' contributing to autism is their potential for introducing aluminum into the body. Increasingly, sunscreens contain aluminum hydroxide and other aluminum salts, which are deemed necessary to produce the small nanoparticles that make the texture more satisfactory (more on this topic shortly). It has recently been argued that the aluminum that is often present as an adjuvant in vaccines may be a contributor to autism, as aluminum has highly toxic properties in the brain.38 It is also conceivable that aluminum in sunscreen disturbs the body's natural protection mechanisms in the skin.

The identification of these many correlations of sunscreen use to autism underscores the need to look deeply into sunscreen's chemical effects. This includes the result of using them – too little vitamin D for proper growth and development – as part of why autism has reached such epidemic proportions. With all the chemicals that our bodies are subjected to today, the increase in autism is most likely due to several chemicals, combined with the possibility that combinations of chemicals create more toxicity along with greater vulnerability. However, researchers need to make this a priority, as 1 in 58 boys' being diagnosed with autism in America in the first part of the 21st century is a burden to society in every way. This includes the strain and stress on the families, resulting in many broken homes, the staggering additional medical and educational costs, and the question of whether these children will be able to function as contributing adults who are needed for a flourishing society.39

It is important to enjoy the sun sensibly, as we need the benefits that it generates. Researchers are recommending that people expose their skin to the sun routinely for the amount of time that does not result in sunburn.**

The Birth of the Nanosized Generation
In addition to the hormonally active chemicals, another major constituent in most sunscreens that has far-reaching consequences results from utilizing materials that are relatively new to humanity. The metals titanium dioxide (TiO2) and zinc oxide (ZnO) are being incorporated into sunscreens as they block out UVA as well as UVB rays. ZnO covers the full long and short range portion of the UVA spectrum, while titanium dioxide filters primarily only the short UVA portion. These metal oxides in their natural form are thick opaque pastes that look like white "goo" on the skin (e.g., white-nosed lifeguards from years ago). To make them more acceptable to the public, manufacturers decided to shrink them down to infinitesimally tiny nanometer-size particles, which results in making them transparent to the eye. To do this, they need to add aluminum salts, which, as mentioned earlier, may penetrate the skin and cause harm in unpredictable ways.

These newly developed nanoparticles are derived from metal oxides that have been considered relatively safe in their full natural state, or bulk form. Due to this reasoning, in 1998 the FDA approved titanium dioxide nanoparticles for use in consumer products without requiring new testing to be performed to determine whether the nanosized metal was as safe as its parent compound. However, research articles state that the radically reduced size results in radically different behavior. The reactivities that they exhibit are so different that researchers still have not been able to develop testing techniques which can adequately determine how these new materials may be toxic to life.

Over the last few years, more and more published articles are sounding alarms over the use of these tiny particles. A 2009 article published in Small Journal demonstrated that TiO2 nanoparticles create cellular damage due to the impairment of cell function, as the nanoparticles result in:

  • decreased cell size.
  • decreased cell proliferation
  • decreased mobility
  • decreased ability to contract collagen.
  • penetration of cell membranes
  • sequestering into vesicles that continue to swell and rupture40

Researchers have also identified that TiO2 nanoparticles:

  • create oxidative stress
  • reduce glutathione and increase hydroperoxide levels
  • kill epidural cells
  • cross both cell and nuclear membranes
  • damage DNA and disrupt normal cell division41
  • cross the protective blood–brain barrier42
  • create reactive oxygen species (ROS) that result in brain neuron death43
  • in exposed mice offspring, large DNA deletions44

This crucial damage could arise in human babies exposed in utero to these microscopic-sized metals.

Nanoparticles Harm Aquatic Life
The promotion of sunscreen use has been so successful that sunscreen chemicals are now found in the oceans, lakes, and rivers of the world even though studies to verify that they do not harm aquatic life have still not been completed.45

In 2011, 12 years after FDA approval, a study published in Aquatic Toxicology concluded that the long-term risks of titanium dioxide nanoparticles are currently unknown. Their results identified that TiO2 caused obvious harm to the zebrafish that they were studying and found accumulation of the nanoparticles in the gills, liver, and heart, as well as the brain of the fish.46

A 2011 review of studies that examined the effects of TiO2 nanoparticles on zebrafish published in Environment International identified sublethal physiological effects including respiratory toxicity, trace element disruption in tissues, inhibition of the cellular sodium and potassium enzyme pump, and oxidative stress. These researchers also highlighted the inability to accurately assess the metabolism of nanoparticles owing to lack of adequate testing methods available to measure the nanoparticles in the tissues.47

ZnO nanoparticles kill plankton. A study published in 2010 in Environmental Toxicology and Chemistry showed that ZnO nanoparticles are toxic to phytoplankton.48 Also in 2010, Toxicology published that ZnO and TiO2 nanoparticles, respectively, are rated as "extremely toxic" and "harmful" to marine life.49

This aspect of killing off marine life is gravely important to the planet. Phytoplankton are not only critical to the beginning of the marine food chain, they are also estimated to be responsible for producing possibly as much as 90% of the world's oxygen supply.50 Researchers have calculated that today there is 40% less phytoplankton in the world's oceans than in 1950. This decline has been seen everywhere except in the Indian Ocean, and in coastal zones where fertilizer runoff from agricultural land has increased nutrient supplies and therefore has supported their growth.51

In the oceans, the chemicals at very low concentrations (same as after showering off the sunscreen) completely bleach (i.e., kill) coral in 96 hours. The chemicals identified that cause the die-off are BP3, octylmethoxycinnamate (OMC), 4-methylbenzylidene camphor (4-MBC), and butylparaben (BP), which is used as a preservative.52 Sunscreens marketed with labels stating that they are safe for coral reefs often contain the above chemicals, as well as TiO2.53

In sampling aquatic life forms, toxic changes are seen in the offspring of fish exposed to the chemical sunscreens. The offspring show reproductive harm by exhibiting a combination of male and female sexual development in their testicle and egg compartments. This occurs to such a strong degree that researchers have coined the term intersex for these chemically affected offspring. The damage is so great to some that they even stop spawning.54

This much reproductive disruption in fish identifies the possibility that this could be happening in all species of life, including human fetuses that are exposed to mixtures of great quantities of the potent hormonally active sunscreen chemicals.

Finally, there is complete ecosystem toxicity, as they are finding these chemicals and metals in all aquatic and marine species tested, and are seeing an accumulation of them as they move up the food chains in both environments.55 In 2010 in Marine Environmental Research, the researchers state that their environmental risk assessment calls for more testing to be done, as they found that combinations of the chemicals on the surface of the waters are putting sensitive species at risk.56

Mother Nature's Solar Radiation Antidote: Antioxidants
Amazingly, the antidote to solar radiation has been with us forever: our naturally abundant antioxidants. These powerful molecules not only work well in preventing cellular damage throughout the body, they also protect the skin from radiation damage, no matter which form, whether it is in the UV or the NIR range. This alone makes their use provide far greater protection than the narrow spectral UV coverage provided by individual chemical sunscreens, or even a fuller UV coverage when several are added together. Studies show that many antioxidant foods prevent the harmful changes that occur at the cellular level when we stay in the sun too long.*** Solar protective antioxidant products can also be purchased.

When shopping, it is important to be aware as well of what products may be harmful, and to read the labels of everything that you buy, because most cosmetics, body lotions, and shampoos contain sunscreens. Titanium dioxide is approved in the US by the FDA as a food additive and as a result is added to many food products, including those sold in health food stores.57 Look at all labels, from perfumes to soaps to puddings, as sunscreens are being utilized to protect the color of many products. Perfume presents a particular problem, however, because their formulations are proprietary information and manufacturers are not required to disclose every component.

Bring Back Protective Clothing
Covering up from the sun completely is not a good idea, because it not only decreases the body's ability to manufacture vitamin D, but also prevents tanning that can be a beneficial sunscreen owing to the protection created from the increased melanin. Fashions have changed much over the years, and it can become fashionable to protect our skin by wearing clothing with longer sleeves and skirts or pants, as well as hats and gloves, which were fashionable for women only a half a century ago.

We can learn from Australia's SunSmart program, which used public service television messages to encourage more clothing cover-ups for children and to bring covering-up styles back into fashion again. The SunSmart promotion has resulted in a reduction of melanoma incidence and mortality rates in Australia's younger population.58 Because of this promotion, Australian businesses offer more protective lines of clothing for children than can be found in other countries.

Some manufacturers have designed UV cloth and clothing that is impregnated with TiO2 or ZnO nanoparticles. This impregnation results in the material's being antimicrobial and therefore it is being promoted for hospital use. These nanoparticles wash off into the water, as shown by the fact that they no longer offer this protection after approximately 20 washings. However, it is not necessary to resort to this material, as tightly woven cloth keeps out the sun. This would be a better solution than to have these metals grinding into the skin and entering either the body's ecosystem or our planet's ecosystem through the wash water runoff.

There is no need to keep contaminating our planet. Many environmental programs have been initiated to protect it, yet simply changing from toxic chemicals to helpful antioxidants for sun protection will help restore the oceans' corals, the plankton population, and the reproductivity in our fish, and protect our health and that of our newborns and children for the future generations to come.

** Helping readers identify what is best for them, Sunscreens – Biohazard sorts through the various and confusing recommendations present today in the medical community regarding sufficient vitamin D blood levels, the amount of time needed to be spent in the sun to manufacture adequate levels of vitamin D, and the appropriate supplemental dosage required to achieve optimum levels. Most important, this book brings awareness to the action steps that the world population needs to take to reverse the present vitamin D deficiency pandemic.

*** Sunscreens – Biohazard has a complete chapter covering the numerous types of antioxidant foods that studies show prevent these harmful changes. It also includes handy shopping reference guides for both the solar protective antioxidants that are discussed in the book, and the multitude of sunscreen chemicals to avoid. These will make shopping for any product easier and help avoid the many sunscreen chemicals that are in countless products today, including those that you have not considered in the past to contain sunscreen chemicals.

Dr. Elizabeth Plourde
P.O. Box 14133
Irvine, California 92623-4133

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Dr. Plourde is a clinical laboratory scientist, medical researcher, author, and international speaker who specializes in hormones and hormone balance, especially at menopause. Certified by the North American Menopause Society as a Menopause Practitioner, her expertise in this field became essential to explain the full impact that sunscreens have on humans and other life on the planet, as they act as potent estrogens and antitestosterones. More information on Sunscreens – Biohazard: Treat as Hazardous Waste is available at:


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