In the sun care industry, zinc oxide (ZnO) is a popularly used ingredient in sunscreens and sun blocks. Over the years there have been many medical studies pointing to the notion that a number of commonly used ingredients in sun care products have been shown to be potentially toxic or hazardous to humans. Although products like sunscreen and sun block are applied to the skin and are not ingested, some studies have found that certain ingredients have the ability to become absorbed into the skin, allowing it to become present inside the human body.
As the list continues to grow for which ingredients the public should be wary of, the sun care industry has sought other means of developing sunscreen and sun block with ingredients that carry a good reputation. Zinc oxide is one of them, along with titanium dioxide. Now becoming one of the main ingredients in many sunscreen formulations, ZnO has become increasingly popular with both organic, or natural, sun care brands.
Although ZnO is able to successfully filter out both UVA and UVB rays, it also causes an unsightly white, chalky appearance when applied to the skin. Many people are familiar with this when used by sportsmen such as cricketers or surfers on their noses and lips. Luckily, with time the formulations have become much more advanced and new technology has been able to reduce the size of the ZnO particle through a micronized process. This means that the actual size of the ZnO particles are small enough that it won't leave a white residue on the skin but is still potent enough to protect the skin from ultraviolet and free radical damage.
The ideal sunscreen would be a physical block using titanium dioxide or ZnO. Titanium dioxide is derived from titanium, a highly reflective white chalky mineral. In addition to being nonirritating and non-allergenic, titanium dioxide is non-comedogenic, meaning that it doesn't produce or aggravate acne.
However, ZnO also provides physical protection from the damaging rays, absorbing primarily UVA light rather than scattering or reflecting it. The UVA rays are the ones that penetrate the skin deeper, causing premature aging as well as potential skin cancers, including melanomas. They do not help the skin to produce Vitamin D, as do UVB rays. Zinc Oxide is also a mild antimicrobial and wound healing substance and is considered to be non-comedogenic.