Ecotoxicologist Craig Downs describes his main work goal as "preventing zombies" — communities of coral or other marine creatures that appear to be thriving, but upon closer inspection, turn out to be composed only of adults lacking the ability to reproduce. These populations are like the "living dead," a generation away from vanishing, according to scientists who discovered them in dying reefs across the Caribbean in 2016.
Globally, coral reefs are in decline for a number of reasons, including climate change, coastal development, and pollution. Over the years, Downs, executive director of Haereticus Environmental Laboratory in Virginia, has studied sunscreen, microplastics, and most recently, beach showers, in an effort to understand the effects of these human-made substances on some of the world's most popular vacation destinations. His latest study, published in July, could also breathe new life into an old law.
In April, the Clean Water Act, the keystone U.S. law on water pollution, took what many environmentalists describe as a tough hit. In a controversial shadow docket decision, the Supreme Court voted to remove states' power to block federally-approved, but environmentally-damaging projects. Commentators decried the attempt to strip states of the right to protect their own waters, one of the core principles enshrined in the Act.
Downs' study, which suggests that beach showers are leaching pollutants into the sea, concerns another part of the law — section 502, subsection 14, to be precise. He and his colleagues allege that the showers are "point sources," defined by the Clean Water Act as "single identifiable sources of pollution from which pollutants are discharged." If Downs and his colleagues are right, attorneys say, this would meaningfully change the current understanding of the 50-year-old statute, potentially allowing citizens to sue many an unsuspecting municipality or resort.
"I wasn't very surprised to hear about this study," said Peter Prows, managing partner of the environmental law firm Briscoe Ivester & Bazel in San Francisco. One of his clients, the Republic of Palau, in the western Pacific, banned several sun filters after connecting a crash in its famous golden jellyfish population, in part, to the sunscreen pollution left by tourists.
In Hawaii, nearly a decade ago, a lifeguard by the name of Tamara Paltin — now a Maui politician — asked Downs how much sunscreen was coming from a local beach shower that drained over the pavement and nearby grass. She also wondered about the showers in the rest of the county, which includes Maui and three other islands. Many of the facilities discharge their wastewater straight into the sea.
Although he was researching sunscreen pollution at the time, Downs didn't think anything of it. Years later, William White, a co-author on the new paper, told Downs about erosion caused by another shower at Waialea Bay on Hawaii Island, and insisted Downs take a look. "He pressed it into my brain," Downs said. "The people who lived there have always wondered if it was an issue."
When Downs and his colleagues tested the ground and water around the showers on three Hawaiian islands in 2019, levels of sunscreen chemicals, including oxybenzone, avobenzone, benzophenone-2, octocrylene, and octinoxate, were disturbingly high.
The resulting research paper is punctuated with references to pollution discharge permits and precise statutory definitions of "pollutants" and "point sources." The first few lines of the discussion section echo the opening paragraphs of the U.S. Supreme Court's opinion in County of Maui vs Hawaii Wildlife Fund, a case in which a group of local NGOs fought a water-polluting county — and won.
That this feat was possible hints at the power contained in the Clean Water Act. Enacted in 1972, it had bold aims: to restore and maintain the integrity of the nation's water, and eliminate water pollution by 1985. To achieve them, lawmakers packed the statute with a variety of tools, among them, "citizen suits," which allow ordinary Americans to take legal action against polluters — a right exercised by Hawaii Wildlife Fund against Maui County Council.
The county had argued that pollutants seeping from injection wells where it stored wastewater were not a point source discharge, because the wells didn't discharge directly into the sea; the waste traveled there indirectly, through the groundwater. The Court decided that the Act's "language, structure, and purpose" would never have left such a large loophole open to polluters.
Any case against beach shower pollution would have to establish that sunscreen is a pollutant. According to Anupa Asokan, senior ocean advocate for the National Resource Defense Council and a board member for the environmental nonprofit Surfrider Foundation, "There's science to back up the fact that some of the chemicals in sunscreen aren't great for coral." Downs himself has published a number of papers on this, including a 2015 study suggesting that oxybenzone and octinoxate could contribute to the bleaching of Hawaiian reefs. These findings led to a statewide ban on the two chemicals.
Yet much remains unknown about the ecological effects of sunscreens. Earlier this month, the National Academies of Sciences, Engineering, and Medicine issued a report, urging the U.S. Environmental Protection Agency to conduct ecological risk assessments for each active ingredient in sunscreens sold in the U.S. The NAS report noted that "Sunscreen is used as a critical tool for the prevention of UV skin damage and skin cancer; however, specific UV filter ingredients may also impact the health of aquatic environments, resident species, or ecosystem services."
Stefanie Harrington, a spokesperson for the Personal Care Products Council — a trade group representing the cosmetics and personal care products industry — re-emphasized sunscreen's role in reducing skin cancer. Commenting on Downs' recent paper, she added that Hawaii's waste management infrastructure should be upgraded: "All manner of chemical and biological contaminants that have been shown to impact ecosystems and public health are being released to the environment because of poor waste management facilities and practices in Hawaii."
Any lawsuit would have to convince courts that a shower could really be a point source.
"There is some contention as to what constitutes a point source or not," said Dietrich Hoefner, an environmental and regulatory lawyer at Lewis Roca in Denver, Colorado. "If you look at the Clean Water Act, it says that a point source is 'a discernible, confined and discrete conveyance, including, but not limited to any pipe, ditch, channel, tunnel, conduit, well.'" But historically, he said, "Regulators think of point sources as things that come out of pipes."
When Downs explains why he and his co-authors believe the showers are point sources, he doesn't mention pipes. He sends images of 15-inch-deep gullies rubbed into the sand by the rivulets that stream from the showers every day.
"Is that rivulet a defined, discrete conveyance?" pondered Prows. "You'd get a lot of lawyers to argue about that. Probably in some circumstances it is." He and Hoefner both conjure a shower drain that collects the water, releasing it onto the beach, underground or somewhere nearby, away from the shower, where it will inevitably flow to the ocean. "That would be a discrete conveyance and a point source."
But even if a point source is established, Hoefner spots another hurdle: "Put yourself in the regulator's shoes. You might look at this and go, these people have already been presumably swimming in the ocean, right?" Some of their sunscreen has already washed off into the water. "So should we really be so concerned that a little bit more is coming off an outdoor shower?"
Downs has heard that argument before. "One swimmer, one shower, does it pose a threat? But 500 swimmers and more than 500 showers?" The difference, he says, is all in the concentrations.
Cláudia Mieiro, a marine biologist at the University of Aveiro in Portugal who was not involved in Downs' study, remarked on the high concentrations of sunscreen chemicals found in the sand near the showers. The sand, she said, appears to be acting like a sink for these compounds.
This could disrupt the beach ecosystem, said Downs, evoking the place where ghost crabs dig their holes, sea turtles come ashore to nest, and migrating birds feed.
And what's in the sand ultimately gets into the sea — and coral reefs. That, said Downs, "leads to zombies."
Downs' findings have already prompted legislators to act. Although just published in July, much of the research for the paper took place back in 2019. By the end of 2021, two of its authors, Kelly King and Tamara Paltin, both members of Maui County Council — and whom Downs invited to join the research project to build community engagement on the issue — had already spearheaded an ordinance banning all chemical sunscreens.
For Councilmember King, an environmentalist and former deep-sea diver, the fallout from the Hawaii Wildlife Fund case is still fresh. The case is a cautionary tale for polluting municipalities. But those who hope it signals a vivification of the Act might want to temper their optimism.
"I think a lot of attorneys were surprised when the Supreme Court found that the Clean Water Act actually applied to those groundwater discharges a couple years ago," said Prows. With another big environmental ruling approaching, he said, "I think the safe bet would be to expect that at least the Supreme Court is going to continue to be skeptical about expansive interpretations of the Clean Water Act."
Hoefner agreed: "With this Supreme Court, we've seen a higher level of skepticism of the federal government's ability to act as an environmental regulator and a sort of narrower reading of the applicable laws than maybe we've seen in the past."
So where does all this leave the beach showers?
"If I were a plaintiff, I'd be looking for the right set of facts to bring a case and try to set precedent," Prows said. "It wouldn't surprise me if there's one out there that meets the test in a more compelling way than others. A judge may well be convinced that under those circumstances, yeah, there's a discharge of a pollutant from a point source here, and that's a violation of the Act."
Jea Morris is a journalist based in London. She writes about beauty and the biosphere and her work has appeared in ELLE, Hakai Magazine, and Smithsonian Magazine.