The Best Sunscreens For Boaters: Our Top 5 Picks

Reef-safe,” “all-natural,” “non-greasy,” “chemical-free” … the bottles of goop we buy to protect ourselves from the sun and its damaging ultraviolet rays all make bold (and sometimes indecipherable) claims. Yet most sunscreens look nearly identical once they leave the packaging and get smeared onto your skin. So what’s the difference? We did the research to find the best sun- screens for your health – which won’t leave stains on your seats or leech toxins into the water – so you can spend less time afflicted by decision paralysis in the sunscreen aisle and more time enjoying sunburn-free boating.

SPF what?

One of the first things that stands out on any sunscreen label is SPF, which stands for Sun Protection Factor. SPF offers a number rating, typically from 15 up to 50 or more. The rating is based on solar exposure, which is a factor of both time and intensity. One hour in the sun at 9 a.m. could produce the same amount of solar exposure as 15 minutes at 1 p.m. It also takes less time to receive the same amount of exposure at lower latitudes, on clearer days, and in reflective environments such as on the water.

SPF ratings apply only to UVB radiation, which is the kind of radiation most closely associated with sunburn, skin damage, and cancer. Overall, a higher SPF rating indicates higher levels of protection. But the scale is not linear. An SPF 15 sunscreen will block 93% of UVB radiation, while an SPF 30 sunscreen will block 97%, and SPF 100 will block 99%. There is ongoing debate among dermatologists about the “right” level of SPF protection, but most agree SPF 30 is usually enough, although there’s nothing wrong with going higher.

In addition to the SPF rating, you’ll also want to look for “broad-spectrum” sunscreens. As well as protecting against UVB radiation as indicated by the SPF rating, broad-spectrum sunscreens also protect against UVA radiation. UVA radiation is less associated with sunburn, but it is associated with premature skin aging, wrinkles, and some cancers. Broad-spectrum sunscreens ensure you have all your bases covered.

Whatever sunscreen you choose, the real key to getting the most out of it is using it as suggested. Reapply at least every two hours (or as recommended), and more often if you’re sweating or jumping in and out of the water because no sunscreen is truly “waterproof.” Store your sunscreen in a cool, shaded location, and discard after its expiration date.

Overall, the best thing you can do for your skin health is to think of sunscreen as just one tool, as it’s rarely enough when spending full days on the water in the blaring sun. Sunscreen should be used in combination with sun-protective clothing, polarized sunglasses, and breaks in the shade. And – it can’t be emphasized enough – reapply, reapply, reapply!

For the love of the water

Recently, scientists have raised questions about the impact that sunscreens may be having on the marine environment, especially coral reefs. Some states, notably Hawaii, have even banned certain types of sunscreens due to these concerns. But terms like “reef-safe” and “reef-friendly” aren’t regulated, so there’s no guarantee that the “all-natural, reef-safe, ocean-lover’s” sunscreen you just picked up is any different than the generic one next to it. Additionally, boaters may have noticed (and complained) that some sunscreens seem to leave stains or residues on fabrics. So what else should boaters be looking for on that label, besides SPF rating and broad-spectrum coverage?

This will disappoint some, but for more boat-friendly and environmentally neutral sunscreens, opt for creams or lotions instead of sprays. A well-applied sun cream is likely to offer more protection than a spray, simply because a spray is more likely to result in thin and patchy coverage. A lotion also stays where you put it, whereas spray can drift into the water or onto boat fabrics where it can stain or result in an unpleasant, greasy seat. The rubbing in required by lotions also tends to result in more absorption, which leads to better protection and less runoff into the water or onto the boat.

Once you’ve committed to a sun cream, turn over your potential purchase and look at the ingredients. Research is ongoing about which ingredients are truly best or worst for the marine environment, but there is some consensus worth mentioning. To understand what these ingredients are and what makes them good or bad, we need to understand the difference between chemical and mineral sunscreens.

Chemicals, minerals & ­nanoparticles

Some sunscreens protect skin from UV radiation with chemical filters that actively absorb UV radiation and dissipate it as heat, preventing it from penetrating your skin. But they can also adversely react with the environment around them, including your boat’s materials and marine life. The current consensus is that oxybenzene and octin­oxate are likely the worst for the marine environment. The reactive properties of other chemical filters found in sunscreens are less known, but any chemical has the potential to react negatively with the environment or your boat’s vinyls or fiberglass. So to be on the extra-safe side, opt for mineral-based sunscreens.

Mineral sunscreens use ingredients like zinc oxide and titanium dioxide to physically block UV rays from reaching your skin, as opposed to absorbing and dissipating them like chemical sunscreens. If the list of active ingredients does not include either of these minerals, the sunscreen likely works with chemical filters.

These nonreactive minerals are far less likely to pose a threat to your boat or to the water, but there are distinctions even within mineral sunscreens. Some research has shown that titanium dioxide can react with seawater to create hydrogen peroxide, which is toxic to marine life. Other research has shown that nanoparticles (ultratiny particles) of any mineral, whether zinc or titanium, can be more likely to dissolve and leech into the water.

Lifeguards know best

Given the lack of transparency in labeling, and ongoing environmental studies on sunscreens, what should a responsible boater use? Perhaps the most surprising conclusion is that the best sunscreen for your body, boat, and soul is good, old-fashioned zinc. But that doesn’t mean you have to walk around with a white lifeguard stripe on your nose; most zinc-based sunscreens rub in clear or near-clear.

If you’re looking for the best of the best, look for broad-spectrum, SPF 30 or higher mineral sunscreen lotion with the only active ingredient being non-nano zinc oxide. If that’s not available, use any mineral sun cream. If you don’t like the look or feel of mineral sun creams, use a chemical sun cream without oxybenzene or octinoxate. We’ve done the homework for you (see page 31). Be sure to use a sunscreen no matter what, and if you can use one of these preferred brands, all the better for your boat and for the environment.