“We were very pleased with the attendance and we had some really excellent speakers,” observed FLSCC Chair Marisa Bailey-Furlonge. “We had presentations by the FDA, presentations on alternative testing methods, effects of microbiome, and many other relevant topics on the safety and efficacy of sunscreens. Overall, it was a great conference and we thank everyone for their support.”
The opening session, chaired by former SCC President Perry Romanowski of Element 44, included presentations on the skin microbiome, natural approaches to repairing damage caused by sunburns and a dermatologist’s perspective on sunscreens.
The doctor’s opinion on sunscreens? Use them! Dr. Loretta Ciraldo, MD, a dermatologist based in Aventura, FL, reviewed research into how well SPF protection prevents skin cancer in the US. For example, in 2006, JC van der Pols reported that basal cell carcinoma tumor rates tended to decrease but not significantly in people formerly randomized to daily sunscreen use compared with those not applying sunscreen daily. Corresponding squamous cell carcinoma tumor rates were significantly decreased by almost 40% during the entire follow-up period.
Armed with supporting data such as these, Ciraldo tells her patients to:
- Purchase multiple SPFs;
- Decide which you like best and stick with it;
- Find a formula that goes on easily, evenly and leaves skin looking and feeling comfortable; and
- If swimming, use waterproof; if exercising, get sweatproof.
Yun Shao, VP-R&D, Kobo Products, presented a paper evaluating metal oxides for full spectrum solar protection from UV, HEV to IR. He noted that titanium dioxide with a primary size in the range of 30-60nm can be used to block HEV light. Furthermore, 35nm TiO2 was found to be most effective and provide 30-50% of attenuation at 5% use levels. According to Shao, micron size TiO2 can block IR effectively. It can provide up to 50% attenuation and good aesthetics at a use level of up to 5%.
“Use of transparent iron oxide or extra fine earth tone pearl mitigates blueing associated with a high level of TiO2 and, therefore, enables higher HEV attenuation,” he explained. “Using TiO2 of properly selected sizes and shapes, high level of full spectrum protection against UVB, UVA, HEV and IR can be achieved. Combining HEV IR TiO2 with organic sunscreen actives will also provide the same high performance to sun care products.”
Sanam Fazilova, technical marketing manager at Active Concepts, detailed how the skin microbiome may provide a solution to UV-induced skin cancer. She noted that certain strains of Staphylococcus microorganisms produce secondary metabolites that are beneficial to the host in calming inflammation, preventing pathogenic invaders and preventing the synthesis of damaged DNA. Moreover, production of 6-Hap in S. epidermis species is universal, these bacteria species reside in human skin, according to Fazilova.
“The observation suggests that certain skin commensal bacteria may help potentially defend the host against skin neoplasia,” she said.
Fazilova maintained that skin commensal bacteria exhibit potential carcinogenesis preventative properties. Based on this evidence, the skin microbiome may contribute to aspects of host defense that include prevention of DNA synthesis in UV-induced damage. However, she noted that daily use personal care products contain preservatives and additives to uphold formulation integrity, but cause damage to skin commensal bacteria.
“Non-viable postbiotic secretions v. viable probiotic cells support these claims without compromising the integrity and safety of a formulation,” concluded Fazilova. “Probiotic-derived natural antimicrobial peptides capture a sustainable fermentation technology with controlled postbiotic approach which is gentle on both the environment and the skin.”
Get an Education!
Prior to the symposium, the Society of Cosmetic Chemists (SCC) held a continuing education program entitled “Modern Sunscreen Formulation—Is It Possible To Please Everyone?” The course was instructed by Mark Chandler, ACT Solutions Corp., and Julian Hewitt, JPH SunCare Technologies Ltd. The presenters provided a brief history of the Sunscreen Monograph, followed by an update on “reef-safe” sunscreens.
Chandler noted several destinations are just saying “no” to oxybenzone and octinoxate, including Hawaii, Key West, US Virgin Islands, Bonaire, Palau and some Mexican resort areas. Chandler told attendees that 4,000-6,000 tons of sunscreen enter reef areas annually and that 90% of snorkeling/diving tourists are concentrated on 10% of the world’s reefs. What’s the issue with oxybenzone and octinoxate? Oxybenzone leaches coral of its nutrients and damages DNA, bleaching it of its fluorescent color, according to Chandler.
In addition, organic UV filters can induce the lytic viral cycle in zooxanthellae with latent infections. Zooanthellae are single-celled dinoflagellates that live in symbiosis with corals and other marine invertebrates.
In regard to inorganics, researchers found no link to star coral mortality; furthermore, nanoparticle zinc oxide is less toxic toward crustaceans and fish. And while at high enough concentrations, ZnO encapsulated nanoparticles are shown to be toxic to mussels, these levels are unlikely to be reached in natural marine waters, according to Chandler.
What does the data mean for sun care formulators? If all organics were to be banned, zinc oxide and titanium dioxide can still be used to achieve high SPF, according to Hewitt, who pointed out that zinc oxide is typically less whitening than titanium dioxide and is capable of SPF50 protection in optimized formulations. He told the audience that the most elegant systems are usually based on a combination of zinc oxide and titanium dioxide.
Hewitt detailed how formulators can create elegant sun protection products whether they select organic or inorganic UV filters. He explained desired aesthetic properties for rub-out, including high spreadability, low waxiness and whiteness and warned attendees that “oiliness and greasiness should be low, but not excessively so,” while at the same time, “absorbency should be fast, but not too fast.”
After-feel properties should include low gloss, whiteness and stickiness and greasiness, but at the same time, “consumers are looking for a smooth feeling on skin after application,” he advised.
For more on the Sunscreen Symposium, visit Happi.com for a roundup video as well as Nadim Shaath’s column on the presentation by FDA’s Theresa M. Michele, MD.