Maxiblock sunscreens do not contain oxybenzone or octyl methoxy cinnamate and are therefore deemed reef safe in compliance with the Hawaii bill S2571 now in effect. But does this make our sunscreens marine friendly?
The Hawaii bills
Effective 2021 Hawaii State is banning sunscreens using oxybenzone or octyl methoxy cinnamate after studies showed that those two UV filters can cause genetic damage to marine life including coral reefs. That ban had little relevance for Australia as oxybenzone or octyl methoxy cinnamate are barely used for Australian sunscreens.
Hawaii state also voted a new bill in 2021 that, if passed to law, would ban two additional UV filters, octocrylene and avobenzone, but not zinc oxide. What is the science now saying?
Latest scientific input
There is a public perception that inorganic UV filters such as zinc oxide are less toxic for corals than organic UV filters, however this is not confirmed by recent publications from Centre Scientific de Monaco or Wageningen Marine Research.
These publications also show that the newer organic UV filters are less toxic to the environment compared to the older organic UV filters and zinc oxide.
The effective impact of sunscreens on marine life remains however elusive, and the situation was put into perspective by one of Australia’s most recognised experts on the Great Barrier Reef, Professor Terry Hughes from James Cook University: "People make a long list of bad things that human beings do to coral reefs - I would place sunscreen at number 200".
Australian 4 hours water-resistant sunscreens best suited for marine friendliness
Australian sunscreens that meet the exceptionally stringent Australian 4 hours water-resistant standard are designed to stay longer on the skin and not wash off easily. Consequently, the amount of UV filter dispersing into the water will be significantly less compared to sunscreens without water resistance or those meeting only the less stringent US or European standards.