Research by the Environmental Working Group (EWG) into the safety of 783 name-brand sunscreens has revealed that many products on the market are either ineffective or actually unsafe.

Overall the review has revealed that 84% of the 783 sunscreen products examined contain ingredients with significant safety concerns, or which do not offer adequate protection from the sun. In fact, one out of every eight high-SPF sunscreens does not adequately protect from UVA radiation, the sun rays linked to skin damage, ageing, immune system problems, and potentially cancer. Instead they protect only from sunburn (UVB radiation).

It was also found that many sunscreen ingredients actually degrade when exposed to the sun, thereby letting all the UV radiation into the skin. Over half (54%) of the products on the market contain ingredients that are unstable alone or in combination. This raises serious questions about the length of time sunscreens are actually effective once applied.

Another cause for concern is the nano-scale ingredients now found in many sunscreens. Little is currently known about the health effects of nanoparticles on the environment and human health. It has been suggested that insoluble particles could penetrate into the skin, and that their high surface to volume ratio could give the nanomaterials unique toxic properties.

Already, it has been shown that some sunscreen ingredients release skin-damaging free-radicals in sunlight. Others have been linked to allergic reactions, or have been shown to act like oestrogen, which has the potential to disrupt hormone systems.

Finally, misleading and false marketing claims are common. The labels on many bottles include untrue statements such as “all day protection”, and “blocks all harmful” rays.

EWG’s analysis is based upon US government and academic sources and an extensive review of technical literature for sunscreens. An online consumer safety assessment tool has been launched alongside the study, according to which out of the products analysed, the use of only 128 products is recommended. A list of them can be found on the Cosmetics Database.