Cruise ships have become the symbol of all that’s gone haywire in the tourism industry.

The largest of these floating hotels are the size of horizontal skyscrapers and carry as many as 6,000 passengers. They cross the seas polluting the water and air and overwhelming their ports of call. Their accidents make headlines: from the deadly capsizing of a ship off the coast of Italy to a child drowning because no lifeguard was on duty.

This lack of modern regulations is the core problem and the chief reason why cruises are so popular. Less regulation translates into cheaper tickets ($389 for seven days in the Bahamas!) Cruises make their big profits once passengers are onboard from alcohol sales, gambling and those on-shore excursions.

Plus cruises are easy – one bed, no decisions.Every day the average cruise ship dumps 21,000 gallons of human waste, one ton of solid waste garbage, 170,000 gallons of wastewater and 8,500 plastic bottles in the ocean. That’s according to the Environmental Protection Agency – cruise ships are under no regulatory obligation to monitor or report what they release.

Congress has allowed these behemoths to operate like a Vegas resort without any of the regulations that apply in the United States. Thanks to Congress, cruises are exempt from: labor laws (waiters are paid $50 a month plus tips and no benefits); most sewage and water regulations under the Clean Water Act; and standards of the Clean Air Act in international waters.

Carnival and Royal Caribbean are headquartered in Miami and, with their subsidiaries, represent nearly two-thirds of the global cruise business. Yet they largely operate outside of most American regulatory laws – and pay almost no corporate taxes. They do this by flagging and registering their ships in other nations (Liberia, Panama and the Bahamas) and winning the right from Congress to be treated in most instances like a commercial vessel and not a hotel.

Since Congress hasn’t budged on these issues – cruise lines are generous donors – local and regional authorities have stepped into the breach.

Citizens of cities as different as Venice, Italy, and Charleston, S.C., are trying to block the biggest ships from docking. Vancouver banned cruise ship air pollution during the Olympic Winter Games. Belize has restricted cruise passengers to one beach area – a practice known in the industry as a sacrifice zone – to protect other ares from being trashed.

The E.P.A. has endorsed new California laws forbidding cruise ships from discharging any waste along its coast. Antarctica banned all large cruise ships because its fragile environment can’t afford a single accident.

Consumers can do their part by finding a cruise that respects the environment from online resources like “The Cruise Report Card” by Friends of the Earth, and “Eco-Friendly Cruises” by Nerd Wallet.

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