According to the article abstract, while formulations such as sunscreens containing titanium dioxide and zinc oxide protect in the UVA and UVB wavelengths, they provide limited protection against high energy visible (HEV) light, also referred to as blue light, to which consumers are frequently exposed through the use of electronics such as smart phones and tablets.
As such, a formula was developed by Colorescience combining red, yellow and black iron oxides, each with different attenuation profiles, and tested for its attenuation of blue light. In addition, it comprised zinc oxide, titanium dioxide and patented skin care ingredients.
The percent of HEV light (400 nm to 490 nm) filtered by the formula was measured using diffuse transmittance spectroscopy. Results revealed 71.9% to 85.6% attenuation across the 415 nm to 465 nm wavelengths.
Co-author on the study, Patricia Boland, VP of Research and Development for Colorescience, said “We formulate Colorescience products using iron oxides because they offer both therapeutic and color-corrective benefits. They are excellent at mitigating the white cast sometimes seen in all-mineral SPF products while also protecting skin from high energy visible (HEV) light, or blue light."
She continued, "Maximum protection potential is determined not only by the total concentration of iron oxides, but also the color combination and processing methods used. Our test method allows us to directly measure the amount of blue light protection each product provides across the entire HEV spectrum, so we can share actual and not theoretical data.”