Researchers from Mblue Labs and the University of Maryland have identified Methylene Blue as a promising broad-spectrum UV blocker with anti-ageing properties that pose minimal threat to marine life.
A summer’s day spent swimming at the beach could only mean one thing – lathering ourselves with bottle and bottles of sunscreen. While the bright sun rays are known for supporting the production of vitamin D, many are now aware that excessive exposure to UV rays can lead to a number of harmful effects including but not limited to premature ageing, skin damage, and cancers.
To protect ourselves, we turn to using sunscreens to prevent skin damage. However, 80 per cent of chemical sunscreens today contain oxybenzone, a chemical UV blocker that ultimately makes its way into our oceans and is absorbed by corals, causing permanent DNA damage. In a bid to prevent further destruction of the marine ecosystem, oxybenzone and its associated derivatives have been banned in several countries and US states, sparking the search for a safer alternative.
Researchers from Mblue Labs and the University of Maryland investigated the UV shielding powers of Methylene Blue, a known salt used for medication and dye, on human skin cells and corals. Using human keratinocytes and skin fibroblasts from young and old donors, the team assessed the effectiveness of Methylene Blue as a UV blocker and compared it with oxybenzone. They found that Methylene Blue not only showed promising results in absorbing both UVA and UVB like traditional sunscreens but also in assisting repair of damaged DNA caused by UV irradiation.
"We are extremely excited to see that skin fibroblasts, derived from both young and old individuals, have improved so much in terms of proliferation and cellular stress in a methylene blue-containing cell culture medium," explained the study's senior author Dr Kan Cao, Founder of Mblue Labs, Bluelene Skincare and a Professor at the University of Maryland Department of Cell Biology and Molecular Genetics.
The team proceeded to investigate the impacts of Methylene Blue on corals, specifically a soft coral species called Xenia umbellate. Based on their findings Methylene Blue easily surpassed oxybenzone which caused severe coral bleaching and death in less than 7 days. Methylene Blue was found to pose significantly fewer adverse effects on coral health at low or high concentrations.
"Our work suggests that Methylene Blue is an effective UVB blocker with a number of highly desired characteristics as a promising ingredient to be included in sunscreens. It shows a broad-spectrum absorption of both UVA and UVB rays, promotes DNA damage repair, combats reactive oxygen species induced by UVA, and most importantly, poses no harm to coral reefs," said Dr Cao.
Additionally, this UV-bocking salt has appeared to be a powerful antioxidant, demonstrating potent benefits to reduce cellular oxidative stress even when contrasted with Vitamin A (Retinol) and Vitamin C.
"Most surprisingly, we found that the combination of Methylene Blue and Vitamin C could deliver amazing anti-ageing effects, particularly in skin cells from older donors, suggesting a strong synergistic reaction between these two beneficial antioxidants," explained Dr Cao.
The team concluded that Methylene Blue has shown promising potential to be a highly effective alternative to oxybenzone, offering broad-spectrum UV protection against both UVA and UVB without compromising coral health and marine ecosystems. Providing added benefits of anti-ageing and DNA repair, this discovery is expected to propagate the use of Methylene Blue as an environment-friendly substitute for harmful chemical sunscreens.
Source: Xiong et al. (2021). Ultraviolet radiation protection potentials of Methylene Blue for human skin and coral reef health. Scientific Reports, 11(1), 1-9.