Reef-safe sunscreen in Hawaii: what the law requires

Hawaii state law prohibits the sale of sunscreens containing oxybenzone and octinoxate to protect coral reefs from chemical bleaching, favoring mineral formulations like non-nano zinc oxide.

Cool ocean currents sweep across volcanic reefs as dusk turns the Hawaiian sky to deep violet. Enacted under Hawaii Act 104 in 2018, state regulations established a legal restriction on selling sunscreens containing oxybenzone and octinoxate, which took effect on January 1, 2021.

Hawaii Sunscreen Legislation and Requirements

According to statutory findings in Hawaii Act 104, oxybenzone and octinoxate are associated with coral bleaching and damage to marine organisms. To build upon state legislation, Maui County Ordinance 5306 went further in 2021 by restricting non-mineral sunscreens entirely. The Hawaii Department of Land and Natural Resources (DLNR) recommends physical protection such as rash guards alongside mineral sunscreens utilizing non-nano zinc oxide as safe alternatives.

Marine Ecosystems and Resident Manta Rays

Preserving coral habitat quality directly supports local marine species, including the resident Hawaiian reef manta ray (Mobula alfredi). Reaching adult wingspans between 8 and 16 feet, these filter feeders possess the largest brain-to-body ratio of any fish and can pass the mirror test. The local population is catalogued individually by unique belly spot patterns. When feeding on zooplankton, reef mantas unfurl their cephalic fins—commonly described as horns—to funnel food into their mouths, rolling them back up when cruising.

Big Island Oceanography and Manta Behavior

Along the Kona coast, the steep underwater slopes of the Big Island's volcanoes push deep, nutrient-rich currents upward toward the surface. This upwelling process creates the island-mass effect, yielding a constant year-round plankton supply. Because food remains continuously available, Kona's mantas form a resident, non-migratory population. Unlike static cleaning stations found in other ocean regions, Kona's primary sites function as active feeding stations where mantas execute dynamic barrel-rolls while eating.

Night Snorkeling and Protection Practices

The Big Island features the only reliable year-round manta night snorkel in Hawaii. On evening excursions, powerful submerged lights concentrate plankton into a predictable area to attract filter-feeding mantas. DLNR guidance notes that sunscreen is largely unnecessary for a night snorkel, and rinsing off residual skin products before entering the ocean prevents unwanted chemicals from washing into the water. Swimmers preparing for an evening trip can review details for a Kona night snorkel tour to plan responsible reef-safe practices.

FAQ

What sunscreen ingredients are banned in Hawaii?

Under Hawaii Act 104, the sale of sunscreens containing oxybenzone and octinoxate is prohibited state-wide. Maui County Ordinance 5306 went further by restricting non-mineral sunscreens entirely.

Why are oxybenzone and octinoxate restricted by law?

State legislative findings show that oxybenzone and octinoxate are associated with coral bleaching and cause harm to marine organisms.

What are recommended alternatives to chemical sunscreens?

Hawaii DLNR guidance highlights rash guards and non-nano zinc oxide mineral sunscreens as effective alternatives. For evening water activities, sunscreen is generally unnecessary, and rinsing off residues before entry helps protect marine life.

How does the local environment support Hawaiian reef mantas?

Steep volcanic slopes generate deep upwelling that provides a continuous plankton supply along the Kona coast, supporting a resident population of reef manta rays (Mobula alfredi).