With the start of sunnier days and more UV exposure, you may be thinking about what sunscreen to use this year. Every year, an estimated 6,000 -14,000 tons of sunscreen is discharged into the ocean (Downs et al, 2006). As an outdoor swimmer, you may be concerned about the environmental impact of what you are putting on your skin when entering the water.
What is the problem with sunscreen?
Sunscreens often have ingredients which damage coral reefs and ocean ecosystems. Chemical offenders include oxybenzone, octocrylene and octinoxate, which have been linked to coral bleaching and the disruption of marine life. In 2018, Hawaii passed a law to ban sunscreens containing oxybenzone and octinoxate from 2021. Others have followed, including the U.S. Virgin Islands, Key West Florida and Palau.
In addition to damaging chemicals within the sunscreen, particle size is a consideration. The majority of sunscreens are manufactured using particles which are less than 100 nanometres "nanotised", to prevent a white sheen being left on your skin. As well as being more harmful to aquatic life, nanotised particles are so small that they can enter our bloodstream through the skin, whereas non-nano sit on the surface of the skin. The effect of this on humans is yet unknown. Larger "non-nano" particles are thought to be safer as they sink to the bottom of the ocean and become ocean sediment, causing less risk to marine life and they are also too large to permeate the skin.
Mineral based sunscreens can take a bit of getting used to and some people don't like the white sheen appearance that they can give. A tinted sunscreen can help to avoid this.
What is reef safe sunscreen?
More products are becoming available that class themselves as "reef-safe" sunscreens. The difficulty is that "reef-safe" doesn't have a specific definition or classification. Often, if a sunscreen does not have oxybenzone or octinoxate, it states that it is reef safe, however these aren't the only two chemicals to be damaging to coral or marine life.
The Haereticus Environmental Laboratory (HEL), a not for profit organisation based in USA, provides Protect Land + Sea Certification of products tested for a list of damaging chemicals. Rather than asking companies to self certify to gain the certificate, each product is tested by the laboratory. Products available in the UK that have the certification include Stream2Sea and Tropic.
The current HEL list of damaging chemicals include:
- Any form of microplastic sphere or beads.
- Any nanoparticles like zinc oxide or titanium dioxide.
- 4-methylbenzylidene camphor
- Para-aminobenzoic acid (PABA)
- Methyl Paraben
- Ethyl Paraben
- Propyl Paraben
- Butyl Paraben
- Benzyl Paraben
What should I look out for in a sunscreen?
If you are starting to look out for a more environmentally sunscreen, here are some things to look out for.
- Broad spectrum UVA and UVB protection.
- Water resistance - less likely to come off in the water and provide better protection swimming.
- Avoid harmful chemicals, especially oxybenzone, octinoxate and parabens.
- Non-nano particles.
- Rub on sunscreen rather than spray will avoid excess sunscreen ending up on the sand and in the sea.
- Sustainable packaging - some manufacturers are turning to innovative packaging such as sugar cane resin.
What else can I do?
Reduce the amount of sunscreen you need to use by covering up with a hat, long sleeved swimsuit or a rash vest (UPF rated). Avoid spending time in the sun when it is most intense in the middle part of the day.
We were excited to see that the University of Sheffield and Imperial College London have found a more sustainable way to make zinc oxide using 95% less energy. They hope that this will pave the way for more affordable eco-friendly sunscreens and are hoping to find an industrial partner to take the product to market.
Downs, C.A., Kramarsky-Winter, E., Segal, R. et al. Toxicopathological Effects of the Sunscreen UV Filter, Oxybenzone (Benzophenone-3), on Coral Planulae and Cultured Primary Cells and Its Environmental Contamination in Hawaii and the U.S. Virgin Islands. Arch Environ Contam Toxicol 70, 265–288 (2016). https://doi.org/10.1007/s00244-015-0227-7