9 Reasons Why Oxybenzone Might be One of the Most Dangerous Chemicals in Your House

As a former specialist in Maternal Fetal Medicine (MFM) and Reproductive Endocrinology, I believe the Endocrine Disrupting Chemicals (EDC’s) are already affecting human health and I stopped exposing my family some 30 years ago. Even if they were not harmful, soluble filters gain entry to blood, tissue and brain. In pregnancy they pass through the placenta and bind to the various hormone receptors in the embryo and fetus. This is a bad idea. The World Health Organization report confirms the serious threat that hormone receptors pose to humans and wildlife. What it does not say is the obvious corollary that in our society, soluble sunscreen filters and other small Molecular Weight (MW) sized chemicals smaller than 500 Daltons, like the preservative parabens, are the single most important source of exposure to EDCs.

Sunscreens and their role in our Health

Although hormone disruptors are affecting human reproductive and other endocrine systems, there is a simple way to avoid a major source of EDCs.   There is also a simple way to protect this and the next generation from rising skin cancer rates.

There is a growing list of adverse effects linked to hormone disruptors that must include the soluble sunscreen filters – oxybenzone, avobenzone, homosalate, octisalate, octocrylene and others.

Some of these adverse effects include the following reproductive disorders:

  • infertility
  • polycystic ovarian syndrome
  • endometriosis
  • fibroids
  • breast and uterine cancer
  • prostate cancer
  • oligospermia
  • male infertility

Non-reproductive disorders include:

  • ADHD
  • asthma
  • Parkinson’s
  • Alzheimer’s
  •  thyroid cancer

Each person should make their own choice between two classes of sunscreens. Either use a sunscreen with small molecular weight (MW) soluble filters less than 500 Daltons. They are absorbed through the skin to reach blood, tissue, and bind to some receptors in the brain. They also give incomplete or UVB-biased protection that may prevent sunburn but affords little (if any) protection against skin cancer and photo-aging, where UVA1 rays play the major role. Lack of efficacy is compounded by the risk of serious and often permanent adverse effects, due to hormone disruption and carcinogenicity.

Alternatively, you can choose a balanced sunscreen with insoluble particle type filters with  a MW greater than 500 Daltons.  This prevents entry into the skin as the filter remains within the outer dead layer of skin. A short list of UV Filters meet this criteria: zinc oxide, titanium dioxide, encapsulated octinoxate, Mexoryl SX™, Tinosorb S™, Tinosorb M™, Parsol SLX™, iscotrizinol, octyl triazone, and bisdisulizole disodium.  Only the first 3 are readily available in North America. Often formulas with a good filter are ruined by use of a soluble filter. These particles give more UVA1 protection with balanced UVB/UVA or better protection, and have no possible adverse effects. A balanced sunscreen can lower your melanoma and non- melanoma skin cancer risk and is the best anti-aging measure.

It defies any sensible logic that a parent or expectant mother would select soluble filters if they knew that they attain blood levels and reach the fetus. It is perplexing to me that many physicians continue to recommend their use. Even industry and regulators cannot deny that they attain blood levels. They use the absurd defence that only a small amount is absorbed. No comfort for a small child or unborn fetus. They also ignore the critical fact that these organic compounds are fat soluble and will bioaccumulate in tissue. These filters also come with the instruction to re-apply them several times per day- this can only add to their bioaccumulation in our bodies.

The Oxybenzone Black List

Benzophenone, otherwise known as oxybenzone, gives context to how the danger exists in our everyday lives. Here is an evidentiary blacklist of reasons why this chemical should be banned from personal care products:

#1: It’s Ubiquitous

A 2008 CDC study showed that this chemical is found in 97% of Americans tested, both genders between age 6-70 years (Calafat 2008).  It is still used in 65% of sunscreens in N. America and in over 950 cosmetics, which may explain why it is so pervasive. Women and girls had higher levels of oxybenzone in their bodies than males likely due to differences in use of body care products including sunscreens.

#2  It’s In Our Bodies and Our Children’s Bodies

Other studies confirm the CDC report on this insidious and alarming  concern that this  chemical absorbs through the skin in significant amounts. A previous biomonitoring study reported that 96% of 6 to 8 year old girls had detectable amounts of oxybenzone in their urine (Wolff 2007). An earlier study detected oxybenzone in the urine of all 30 adult participants (Ye 2005).

#3 We Absorb More than You Would Think

Studies on human volunteers indicate a wide variation in the level of oxybenzone absorbed into the body, with some individuals absorbing at least 9% of the applied dose, as measured in excretions in urine (Hayden 1997; Janjua 2004; Sarveiya 2004; Gonzalez 2006). Volunteers continued to excrete oxybenzone many days after the last application of the chemical, an indication of its tendency to accumulate in fatty tissues in the body (Gonzalez 2006).

#4 It Increases Absorption Rates of Other Potential EDC’s

In addition to its ability to absorb into the body, oxybenzone is also a penetration enhancer, meaning it’s a chemical that helps other chemicals penetrate the skin (Pont 2004).

#5 It Has Potential Safety Concerns for Pregnant Women

Mothers with high levels of oxybenzone in their bodies were more likely to give birth to underweight or small for gestational age baby girls (Wolff 2008).

#6 It Could Be Affecting Our Fertility

It was also cited in a NIH report last year as being an important factor in male infertility, according to a study by the National Institutes of Health and the New York state Department of Health’s Wadsworth Center. This study merely underscores what the Endocrine Society, The WHO and The United Nations Environmental Program, have been saying for a decade- that the entire group of about 1000 known hormone disruptors have adverse effects on human reproduction, along with other effects on endocrine function and neural signalling. None of these reports follow through with the deductive analysis that given the patterns of human exposure, it is likely that soluble UV filters represent the most important source of EDC exposure in a developed society.

#7 It’s a Potential Carcinogen

Sunlight also causes oxybenzone to form free radical chemicals that may be linked to cell damage, according to 2 of 3 studies (Allen 1996; Serpone 2002; Hanson 2006). Hence this generation of reactive oxygen species (ROS) could be carcinogenic to skin- this filter could be involved with causing the cancer it is supposed to prevent.

#8 It has Environmental Effects

December 2015 blog.jpg

The Hawaiians Knew- Sign from 2001 from beach in Maui, Hawaii

#9 It’s an AllergenOxybenzone is contaminating  marine environments – washing off swimmers and in  municipal, residential, and wastewater effluent from marine vessels. A 2015 report (Downs et al) confirms other studies over the past decade that oxybenzone is genotoxic, kills larvae of reproducing coral, and converts the planula from a motile to a sessile state by ossification, due to its action as a skeletal hormone disruptor. Coral reef contamination of oxybenzone in the U.S. Virgin Islands ranged from 75 µg/L to 1.4 mg/L, whereas Hawaiian sites were contaminated between 0.8 and 19.2 µg/L.  Oxybenzone poses a hazard to coral reef conservation and threatens the resiliency of coral reefs to climate change.
Oxybenzone and its structural cousin avobenzone are now the leading causes of photocontact allergy (Warshaw 2012). Although this is an infrequent problem, it is just one more reason why this chemical should be banned from personal care products. Consumers and physicians should question its continued use.  In most cosmetics, it’s only used to prevent discolouration in the product. It is still used in over 950 cosmetics and sunscreens.

Are All Sunscreen Actives Created Equally?

All of the organic soluble filters with small molecules (MW in the 250-500 Dalton range or < 1 nm)  should be viewed with the same concern . Many physicians still spread the myth that nanoscale zinc oxide usually 70- 300 nm and titanium dioxide 20-140 nm are so small they should concern us. In the world of sunscreens nano is large – usually  40-600 X larger than the soluble filter group, and nanoscale or micronized particles never penetrate beyond the outer layer of skin. There is a principle in endocrinology – isoform function – whereby chemicals with the same structure likely bind to the same hormone receptor and generally have the same effects. Hence avobenzone and octisalate very likely exert the same toxic effects as oxybenzone and homosalate, known to be hormone disruptors.  Why would anyone defend their  continued use? They enter the blood and brain of any person , including the most vulnerable – the unborn fetus and young children. They give you incomplete protection that could be a factor in rising skin cancer rates, and there is ample evidence that they are hormone disruptors and carcinogens in some cases. Finally, there is the evidence they also affect the health of lower species and destroy our reefs.

The WHO published a 250 page evidence based review entitled “ State of the Science of ENDOCRINE DISRUPTING CHEMICALS 2012 “ representing a broad scientific consensus among the leading experts in related fields. This echoes the warnings in scientific reviews  from The Endocrine Society,  The European Commission and the European Environment Agency. These documents implicate EDCs as a concern to public and wildlife health. In addition, the European Society for Paediatric Endocrinology and the Pediatric Endocrine Society have put forward a consensus statement calling for action regarding endocrine disruptors and their effects. “Of special concern are effects on early development of both humans and wildlife, as these effects are often irreversible and may not become evident until later in life.  The Endocrine Society stated : The evidence for adverse reproductive outcomes (infertility, cancers, malformations) from exposure to endocrine disrupting chemicals is strong, and there is mounting evidence for effects on other endocrine systems, including thyroid, neuroendocrine, obesity and metabolism, and insulin and glucose homeostasis.

The WHO list about 800 possible hormone disruptors, most of whom have never been studied for their possible human effects. Avoiding exposure to the extent you can is important in protecting our children and their children.

As a follow up, my daughter Sara recently posted a reasoned discussion on why all consumers need to be concerned about hormone disruptors on our company blog (click here to read). She presented a persuasive argument on why a prudent person would try to reduce their exposure to these chemicals that now intersect with our daily lives. She is a new mother, and I take comfort from knowing that our precious new person will have little or no exposure to the permanent, serious, and even transgenerational adverse effects of these chemicals. As parents and grandparents, we will be vigilant and do our utmost to prevent her having any exposure.  She also blogged about sunscreen use in her pregnancy (click here to read).


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Dr. Dudley, M.D., FRCS(C) completed his residency in OB-GYN at the University of Ottawa in 1978. He went on to complete joint fellowship in maternal-foetal medicine and reproductive endocrinology at the John Radcliffe Hospital (Oxford University) and the Royal Free Hospital (University of London) respectively. From 1979-1991, he was the Director for the High Risk Pregnancy Unit at the Ottawa Civic Hospital, University of Ottawa. During this time, he was a member of the academic teaching staff for the department of obstetrics and gynaecology. Laserderm was created in 1987 to provide innovative laser treatment for benign vascular lesions including port-wine stain birthmarks and hemangiomas. Dr. Laughlin was the Medical Director and Dr. Dudley the Executive Director while both physicians provided clinical expertise to create a first in Canada program for this type of laser treatment. In 1990, Laserderm became the first Independent Health Facility within Ontario. Dr. Dudley decided to retire from his position at the Civic Hospital in the High Risk Pregnancy Unit and work full time at Laserderm in 1991. He completed a fellowship in Cutaneous Laser Medicine in 1993 and worked alongside Dr. Laughlin in the continued research and development of many of the protocols and laser systems that are now the standard of care. The Laserderm team became renowned for their expertise in all aspects of cutaneous laser medicine. Over the next two decades, Laserderm worked with industry to research and develop new laser technology for several new applications. Laserderm played a role in the research and development for virtually all of the advances made in cutaneous laser medicine. Each new treatment method was pioneered in Canada at Laserderm. Meanwhile, after a patient asked him about the safety of using a sunscreen during pregnancy- Dr. Dudley began investigating the safety of many of the personal care products that are commonly used, paying specific attention to sunscreens. His experience with foetal-maternal health and his time spent in the dermatology clinic led him to create Cyberderm Laboratories with Dr. Laughlin and a Toronto-based chemist Tom Heinar in 1996. His axiom of creating sunscreens and cosmetics that are ‘safe enough for even a pregnant woman to use’ has led him in a life long pursuit of continuous research and development of leading edge skincare products. The company became operational in 2008 with the launch of its first sunscreen and cosmetic products. The product line under the brand name The Sunscreen Company TM is now available nation-wide, including within Laserderm. It continues to grow while Dr. Dudley continues his research and pushes for the commercialization of the most safe and effective sunscreens in the world. Dr. Dudley continues to publish his latest thinking on the industry, sunscreens and the creation of safe cosmeceuticals on his blog The Sunscreen Doc.

2 thoughts on “9 Reasons Why Oxybenzone Might be One of the Most Dangerous Chemicals in Your House”

  1. There needs to be a warning label on all sunscreens that include theses chemicals in order for individuals to make an informed decision.


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