Beach showers are a source of sunscreen pollution for coral reefs

Beach showers near Hawaii’s marine protected areas and other coral reefs are an environmental threat.

A community-based, scientific paper published in the journal, Journal of Hazardous Materials, documents that the sunscreen washed off at beach showers on Oahu, Maui, and Hawai’i pollute the surrounding environment at concentrations that pose a threat to shore and marine ecosystems.

Beach goers put on their sunscreen, swim on Hawaii’s beaches and coral reefs, and when they leave the beach for the day, they use the beach park’s shower amenity. What sunscreen doesn’t come off a swimmer’s body when swimming is washed off at the beach shower.

Unfortunately, none of these showers are plumbed with drains to the municipal sewer system, but instead drain right onto the beach and back into the waters.

Dr. Craig Downs, the lead author of this study, stated that these beach showers are point-sources of pollution, and violate the U.S. Clean Water Act if they are discharging chemicals that can pose a harm to water quality and local wildlife. There are over 535 beach showers in Hawaii, associated with resorts and hotels, and municipal and state parks.

He said that the climate-change factor of rising seas, especially King Tides and higher tidelines, liberate shower pollutants from beach sands in pulses whenever the tides come high onto the shoreline.  Rains can also cause a pulsed discharge from these showers into coastal environments.

Executive Director of the Inland Ocean Coalition, Vicki Goldstein, said, “Science has clearly demonstrated that sunscreen pollution is contributing to the demise of coral reefs and marine ecosystems and reduces the resiliency of these ecosystems that are already impacted by overfishing, plastic pollution, and climate change.”

This scientific paper also raised the issue that recreation tour vessels, which can have between 6-120 swimmers on board, could also potentially be a point-source of sunscreen pollution, especially in marine protected areas such as Molokini, Honolua Bay and Kealakekua Bay Conservation Districts which see hundreds of vessel visitors a day.

“One way dive boats and tour operators can adopt sustainable practices is to promote the use of mineral sunscreens or sun-protective clothing to all their customers as part of a welcome-aboard orientation. We believe these measures help reduce impacts to coral reefs and other marine habitats, and we encourage all dive and snorkel operators to do the same. For example, Aggressor Adventures® has these policies in place as part of their Green the Fleet sustainability initiatives applied across their global operations, from the Caribbean Sea and Pacific Ocean to the Red Sea,” says Samantha Whitcraft, Executive Director of the Sea of Change Foundation and Director of Conservation and Outreach, Aggressor Adventures.

Mendy Dant, one of the co-authors of the scientific paper and Vice President of Fair Wind Cruises in Kailua-Kona not only educates their guests on marine friendly behavior, but lobbied Hawaii DLNR to ensure commercial recreational boats visiting Kealakekua Bay do not use petrochemical sunscreens, such as oxybenzone and octocrylene.

What can swimmers do to mitigate this pollution threat? Marina Scott of Surfrider Foundation’s Maui Chapter states, “The science is clear that sunscreen chemicals are routinely found in the coastal environment and have the ability to pose a serious threat to ocean ecosystems. Switching to more reef-friendly sun management, including covering up and using non-nano, mineral-based sunscreen is an easy and effective way to protect human health and critical marine life.”

The threat of a point-source of pollution to municipalities is serious, these showers can be in violation of the U.S. Clean Water Act.  One solution to this is to regulate the sunscreen chemicals that are threatening the environment.  Maui County Council Members Kelly King and Tamara Paltin led the effort for Maui to pass 2021 Ordinance #5306, which bans the sale, distribution and use of sunscreen containing non-FDA-approved petrochemical sunscreens, such as oxybenzone, octocrylene, and homosalate.  Only FDA-approved mineral sunscreens can be used and sold in Maui beginning October 1, 2022. Last month, Hawai’i County passed a similar law, allowing the sale of only mineral sunscreens.

Other solutions, which are discussed in detail within the scientific paper, is the option to plumb these shower drains to municipal sewage systems, or to collect them in holding containers, treat the shower grey water to destroy or remove the chemicals, and the safely discharge the shower waters into the environment.

Coverage of this scientific article in the media can be found:

1. https://coastalscience.noaa.gov/news/research-determines-beach-showers-are-a-source-of-sunscreen-pollution-to-hawaii-coral-reefs/
2. https://arstechnica.com/tech-policy/2022/09/are-hawaiis-beach-showers-in-violation-of-the-clean-water-act/
3. https://mauinow.com/2022/07/29/journal-article-documents-sunscreen-runoff-from-beach-showers-in-hawai%CA%BBi-as-an-environmental-threat/
4. https://undark.org/2022/09/07/hawaii-beach-showers-violation-clean-water-act/
5. https://beatofhawaii.com/hawaii-beach-showers-study-warns-on-hidden-dangers/
6. https://hakaimagazine.com/news/cleaning-up-beach-showers/
7. https://www.popsci.com/environment/beach-showers-pollution/
8. https://www.thenationalnews.com/uae/environment/2022/04/19/beach-goers-sun-cream-could-damage-coral-reefs-gulf-island-study-suggests/
9. https://www.epa.gov/beaches/learn-what-affects-beach-health
10. https://www.shape.com/lifestyle/beauty-style/non-toxic-biodegradable-reef-safe-sunscreen