High-factor sun cream is a holiday essential, but there’s more than the SPF to consider when choosing one. Formulas have a big impact on marine life, so it’s important for the ingredients to be ocean-friendly as well as kind to skin. Avoid chemical sun creams, which are often full of preservatives and parabens that wash into the water and contribute to coral bleaching. Instead, reach for mineral formulas with non-toxic ingredients such as zinc oxide, which effectively blocks UV rays without causing any harm. These are the four sea-safe sun creams you’ll find in our suitcases.