I have said for over a decade, just about every day, that most sunscreens are neither SAFE nor EFFECTIVE. My “undesirables” singled out for strict avoidance were avobenzone, oxybenzone, homosalate, octisalate, octocrylene, 4-methyl-benzylidine camphor, and regular (non-encapsulated) octinoxate, present in most brand name, drug store, or doctor dispensed sunscreens. I cautioned that consumers should avoid these soluble Polycyclic Aromatic Hydrocarbon (PAH) sunscreen filters that enter blood and tissue through the skin, and are implicated as hormone disruptors and carcinogens that mutate DNA. Most parents and pregnant women are unaware of these established facts.
The FDA now agrees with me. Zinc oxide and titanium dioxide are the only two UV filters proposed to receive a Category 1 or GRASE (Generally Regarded As Safe and Effective) designation. The FDA has placed virtually all the PAH filters used in typical brand name sunscreens on a “watch” list – insufficient data to support a positive GRASE label – safety and efficacy need to be established – to be known as Category III. These include cinoxate, dioxybenzone, ensulizole, homosalate, meradimate, octinoxate, octisalate, octocrylene, padimate O, sulisobenzone, oxybenzone or avobenzone at this time.
While the statutory process is underway, it is very clear is that the prevailing scientific evidence led the FDA to declare that the 12 filters above, including my 7 undesirable, cannot now be considered as safe and effective. In 2008 the Centre for Disease Control confirmed that oxybenzone, the most popular UV filter at the time, was found in 96.8 % of Americans, both genders, ages 6-70. Other studies confirmed that 85.2% of nursing mothers had one or more UV filters in breast milk, and 99% of patients having amniocentesis in the 3rd trimester had oxybenzone in amniotic fluid. The golden rule in endocrinology is “isoform function”, same structure – same actions – where permeation and hormone disruption are concerned. For two decades, I have said that if oxybenzone reaches blood, all PAH filters will do so at different rates, and take varying times to attain steady state and peak levels. The FDA did their own permeation and bioavailability studies, which confirm that all in the group (including avobenzone) attain blood levels. This led to their new proposals when they also decided that the sunscreen issue was very similar to that of BPA. I still ask – why is there not a WARNING label on permeation and a CAUTION to pregnant women, as there is for anything sold in a pharmacy with the potential to reach the unborn.
It is still not clear whether a regulatory framework will emerge that is easy for the consumer to understand and actually leads to safe and effective sunscreens. The new generation of sunscreens must have the ultra UVA protection that contemporary science proves is necessary to prevent skin cancer and photoaging. The FDA finally accepts that better methods are needed to confirm the UVA protection afforded by a sunscreen and a BROAD SPECTRUM claim. They also discuss for the first time that many of the PAH filters like oxybenzone may be estrogenic or act as Endocrine Disrupting Chemicals (EDC), which can adversely affect human and wildlife health. They act by hormone disruption of reproductive and other endocrine systems.
The industrial alliance still argue that there is no real evidence of hormone disruption in humans. Many physicians must not read Endocrine and human or Ecotoxicology literature. This literature is replete with evidence of diverse hormone disruption in humans and wildlife over the past 20 years. A recent statement from an Australian/New Zealand Policy Group again repeated the old and inaccurate claim based on outdated studies in rodents and humans. Humans are not large rodents and endocrine receptor function in humans is unique. A 2016 review of 85 scientific papers in humans and lower species concluded that aromatic hydrocarbon UV filters are generally involved in the disruption of the hypothalamic–pituitary–gonadal system. More recent studies in 2018 confirm that UV hydrocarbon filters, other phenols including the preservative parabens, clearly change levels of virtually every sex hormone, pituitary hormones, thyroid hormones and certain growth factors in both pregnant and non-pregnant women. A change in a hormone level is evidence of HORMONE DISRUPTION. The numerous clinical consequences are another matter, and may not be evident for up to 40 years or more. A 2019 publication showed evidence that the PAH UV filters can affect the timing of puberty in boys and girls. Physicians must remember the first precept or sacred trust in medicine “first do no harm”. Our regulators, policymakers, and legislators must apply the Precautionary Principle.
UV hydrocarbon filters clearly permeate into your blood and attain various levels – reason enough to avoid them. They belong to a group of 1000 plus hormone disruptors, for which the WHO and The Endocrine Society provide scientific data showing the strong evidence for links to adverse effects in humans. These include female reproductive disorders (infertility, uterine fibroids, endometriosis, PCOS), male infertility, reproductive cancers (uterine, breast cancer, and prostate), thyroid cancer, Hirschsprung’s disease and hypospadias in the newborn, childhood disorders (asthma, ADHD, and autism), neurodegenerative problems (Parkinson’s and Alzheimer’s disease), and metabolic disorders- obesity and type 2 diabetes.
Prudent people, especially nursing and expectant mothers, parents of young or adolescent children, and couples trying to conceive will mostly agree with our philosophy as physicians and that of the Sunscreen Company – https://thesunscreencompany.com/ – to apply the Precautionary Principle – err on the side of caution – and the sacred trust in medicine – first do no harm.
It may take awhile for a sensible set of rules and enforcement to emerge and be validated by the test of time. This will become evident when the new ultra UVA sunscreens consistently prevent sunburn and begin to lower N. American skin cancer rates for the first time. In the meantime one easy approach to use in everyday life is as follows:
A GENERAL PHOTOPROTECTION PLAN:
- Practice sun avoidance as much as you can. The usual caution to stay out of the sun between 10 am to 2pm is more a way of lowering your UVB exposure as UVA does not vary much with time of day or latitude. Modern science suggests that UVA is the main driver of skin cancer and photoaging. Use an ultra UVA sunscreen which will also have high UVB protection. High UVB or high SPF sunscreens may have little UVA protection even when labelled as BROAD SPECTRUM. The new rule proposed by the FDA that UVA has to be measured not inferred and that the ratio of UVA1/UV protection has to be > 0.70 are similar to existing EU and Australian requirements.
- Wear sun/UVR protective clothing when outdoors and cover as much skin as you can. It is a very efficient way of providing broad spectrum protection and it reduces the amount of sunscreen you use each day. Dermatologist Sharyn Laughlin uses Solumbra™ for outdoor or vacation sun exposure – it is a tried and trusted brand of UV protective textiles. Wear a hat with a 3-5” brim and use UV protective sunglasses to shield your eyes.
SPECIFIC BUT EFFECTIVE DAILY PHOTOPROTECTION:
- Use SPF 25-50 but bear in mind that most sunscreens have a Real Life SPF in sunlight of 10-15 even if labelled at 50 or more. Reason – the lamp used for the SPF test emits light in a spectrum bearing no resemblance to actual sunlight. Real sunlight has 5X more UVA than the lamp. If you are very fair, assume that the SPF in popular brands may be actually only 10, and adjust your exposure time accordingly. If your unprotected skin burns in 5 minutes, only stay out for 5 times 10 = 50 minutes, and not use 30 or 50 as the multiplier for safe exposure time. The particle sunscreens with zinc oxide from https://thesunscreencompany.com/ do achieve Real Life SPF closer to their label values because of the special nature of the dispersion using proprietary technology.
- A Broad Spectrum label as regulated in Canada and the USA is likely to be untrue. Zinc oxide and avobenzone are the two common UVA filters used. 3% avobenzone or < 14% zinc oxide will only achieve a UVA-Protection Factor (UVA-PF), measured by a valid method of 5-8 – not adequate for any real prevention of skin cancer or photoaging. Avobenzone is unstable and forms nasty complexes with chlorine. I consider it an “undesirable” like its structural cousin oxybenzone. Both are now on the proposed FDA watch list. Mexoryl SX™ and XL™ are patented to L’Oreal and are good broad spectrum filters but they are always mixed with undesirables on the FDA watch list.
- Visit https://thesunscreencompany.com/ for unique ultra UVA zinc oxide sunscreens with patent pending biodegradable dispersing agents that give our sunscreens better Real Life SPF and the best UVA protection in N. America. Our 25 % zinc oxide Simply Zinc Ultra (SZU) affords unmatched UVA protection for everyday as a makeup base or for outdoor and any vacation exposure. Ultra UVA protection is able to prevent the UVA damage that drives cancer. SZU achieves the highest UVA-PF of 20.4 compared with the 5 to 8 or less of virtually all the brands available in N. America. We advise all Canadians to apply a high UVA sunscreen everyday to face, neck and back of your hands or any other exposed areas, every day in every season. A computer derivation shows that if you use a sunscreen with this level of UVA protection daily from a young age, when you are 70 years old you may look like you are only age 45. Daily application of a sunscreen like SZU is a good way to reduce your need for rejuvenation procedures, and to protect your investment after facial rejuvenation (subject for my next blog). Melanoma occurs more commonly in white Americans and Europeans that work indoors and assume they do not need a sunscreen. For most of us, 65% of lifetime UV radiation is ambient, and not from outdoor or vacation exposure
Harm to human health and the environment, particularly the coral and marine habitat, occurs through the same pathway – first permeation then hormone disruption and DNA mutation. Visit my blog https://thesunscreendoc.wordpress.com/2019/02/14/your-march-break-vacation-endangers-the-marine-ecosystem/ . Given the human and environmental harm from typical brand name sunscreens – there is a serious irony present. We use sunscreens to prevent cancer – the undesirable filters give UVB-BIASED protection that cannot prevent skin cancer. They apparently do not, as global rates have doubled since 1960, despite the increasing use of these sunscreens.
Adult exposure to an EDC may have different consequences from fetal or infantile exposure. Endocrinologists use the term “the developmental basis of adult disease”, where developing organisms – the fetus (eutherian mammals), the egg (other vertebrates), and the external environment (such as EDC exposure), interact with an individual’s genes to determine later onset of disease. The latent period may be considerable – the disease may not be apparent early in life but may only become evident in adulthood or senescence.
Since 1991, I have cautioned that UV filters with a benzene ring resembling DDT, petroleum and other phenols, which have estrogenic and other hormone actions – however minimal – cannot be regarded as safe for anyone. It took the FDA over 20 years to agree with me. Better late than never.
© Denis K. Dudley MD, FEB 2019. All rights reserved.