Tropical island nations should team up to ban coral-killing sunscreen products, following the example of Hawaii, a conference has heard. Chemical compounds in sunscreen lotions cause irreparable damage to reefs, which are crucial to the livelihoods of 500 million people in the tropics, scientist and policymakers said at the IUCN World Conservation Congress on 3 September. Hawaii is leading a legistlative effort to ban the use of sunscreen that contains oxybenzone or similar harmful agents at its beaches.