A Great Forecast for Sun Care

The sun care industry limped into 2021 after a COVID-marred 2020 sun care season. US sales fell nearly 9% in food, drug and mass merchandisers, according to IRI Worldwide. Furthermore, the US FDA continued to raise questions regarding the efficacy of some UV protectants. Under these circumstances, organizers couldn’t know what to expect when putting together the Sunscreen Symposium sponsored by the Florida Chapter of the Society of Cosmetic Chemists. Happily, it exceeded all expectations.

The event attracted nearly 500 attendees; that’s down from 600 at the last Symposium due to fewer international attendees, explained FLSCC Sunscreen Symposium Chair Peter Toth of McCullough & Associates, Atlanta, GA.

“It was a great turnout. We worked very closely with Disney to provide a safe environment for everyone,” he explained.

A highlight of the presentations was a strong presence by the FDA, which had four speakers.

The Symposium started with a full-day continuing education course presented by Wen Schroeder of Seki Cosmeticals, Westminster, CO. She opened with a review of the most common skin cancers in the US, and the rising incidence of and declining death rate from melanoma.

“The highest rate of increase in melanoma is among women age 40 to 50,” said Schroeder. “Melanoma diagnosed in young adults aged 18-39 is climbing at an alarming rate.”

She attributed the melanoma increases to vanity—consumers think they look fit if they have a tan. And yet, the $12 billion global sun care market is growing 4-5% a year. While North America and Europe are the biggest markets, Schroeder said the greatest growth is in Asia, where the category is expected to grow 7.4% a year through 2024. She reviewed organic and inorganic sunscreens and warned that zinc oxide can be difficult to work with, due to agglomeration issues. Schroeder reviewed the different regulations around the world, noting that in vitro safety testing is gaining in popularity. She also detailed several formulation trends improving sunscreen efficacy.

“The market is robust with ongoing research and development and a complicated global regulatory environment,” she summarized.

Despite some better chemistry options, Schroeder isn’t optimistic that good science will prevail in a science-illiterate society.

“After a year-and-a-half of living with COVID, I am losing faith that we will be able to educate consumers,” Wen concluded. “Science is messy. We learn something new today and tomorrow.”

Consultant George Deckner tackled the zinc oxide agglomeration issue by noting that a good dispersant will keep particles separate by adsorbing onto the particle and providing a barrier against reagglomeration.  In evaluating dispersants, Deckner said the best were Polyglyceryl 6 Polyricinoleate, PHS and several proprietary blends. The optimum dispersant level for SPF six-month (+) stability using PHS was 5% by weight of the zinc oxide in the formulation.

Deckner had several recommendations for attendees:

• Develop in vitro SPF testing capabilities;
• Always in vitro SPF test aged vs. fresh batches and stability samples (top and bottom of samples);
• Analyze production batches using in vitro SPF as a quality control test;
• Powdered zinc oxide is preferred to using commercial dispersions. It reduces costs and increases formulation flexibility;
• Making and storing uncoated zinc oxide premixes is not generally recommended. Silicone coated are preferred;
• Use silicone coated or uncoated zinc oxide dispersed in the oil phase or uncoated in the water phase for water-in-oil emulsions;
• Use silicone-coated zinc oxide dispersed in oil for oil-in-water emulsions;
• Use 5% dispersing/wetting agent based on the weight percent of zinc oxide used in formulation;
• Formulate SPF boosters in the same phase as the zinc oxide;
• Use 1-2% poly C10-30 alkylacrylate or polyethylene as SPF booster when dispersing zinc oxide in the oil phase of a water in oil emulsion. They can also thicken the oil phase to help stabilize the water in oil emulsion and keep the zinc oxide from settling and possibly agglomerating;
• Use free radical quenchers like ethylhexyl methocrylene or trimethoxybenzylidene pentanedione as SPF boosters when dispersing zinc oxide in the oil phase or water phase of a water-in-oil emulsion; and
• Use styrene/acrylates copolymer (and) acrylates copolymer dispersed in water as an SPF booster when dispersing zinc oxide oxide into the water phase of a water-in-oil emulsion.