What’s local policy got to do with it? Testing the efficacy of federal interventions to protect coastal parks from sunscreen chemical pollution in Hawaii and North Carolina

Abstract

Across the United States, conservation policies often differ based on the local or state jurisdiction, which can present challenges for federal natural resource managers with mandates to protect lands and waters in these areas. To reduce sunscreen chemical pollution in park aquatic ecosystems, the National Park Service (NPS) suggests that visitors apply non-nanotized mineral-based sunscreens and wear sun-protective clothing. In summer 2021, researchers tested whether visitor exposure to interventions promoting NPS sun protection recommendations was associated with these behaviors in two very different local policy contexts. A survey was fielded in July and August 2021 at coastal parks in North Carolina and Hawaii. At the time of the study, Hawaii had implemented a ban on the sale of sunscreen containing the chemicals oxybenzone and octinoxate, whereas North Carolina had no pending legislation. We found similar park visitor behaviors, use of sunscreen chemical formulations, and responses to NPS interventions, regardless of local policy status. At both locations, respondents demonstrated high levels of pro-environmental intent and similar sun protection behaviors. Of the three sunscreen chemical “Os” that have been banned in regions of the United States—octocrylene, oxybenzone, and octinoxate—octocrylene was the most frequently reported active ingredient in sunscreens. Only about a third of sunscreen products reported by visitors included zinc oxide and/or titanium dioxide as the sole active ingredients, formulations most commonly cited as less environmentally harmful. And at both locations, visitor exposure to at least one of the interventions on sun protection related to higher levels of intent to practice the recommended behaviors.