Environmentalists urged Royal Caribbean this week to clean up sewage and wastewater dumped from its cruise ships, in order to protect marine habitats and human health.
Each cruise ship can dump as much as 30,000 gallons of sewage a day, as well as 255,000 gallons of "gray water" from laundries, showers, sinks and dishwashers, the nonprofit advocacy organization Oceana and other groups said at a press conference.
"We're calling on them to end the wake of shame," said Moira Chapin, a field organizer for Environment California.
Oceana organizer Jesse Littlewood said pollution from cruise ships contributes to oxygen-free ocean "dead zones" and algae buildup that kills marine life and potentially threatens human health.
Littlewood called on the company to begin using advanced wastewater treatment systems on all its ships. Royal Caribbean has such systems on three of its vessels, but its other 25 ships use Coast Guard-approved marine sanitation devices that have been deemed inefficient.