The ill-fated Royal Caribbean cruise ship returns home Wednesday, but with an ignoble mark on it.
Nearly 700 crew and passengers fell ill aboard the Explorer of the Seas, the highest number of sick people reported on any cruise ship in two decades, CDC data show.
At least 629 passengers and 54 cruise workers got sick, but not all at the same time.
According to publicly-available data by the Centers for Disease Control and Prevention, that wins Explorer of the Seas the distinction of being the cruise ship with the highest number of sick people in 20 years.
The ship had 3,071 passengers and 1,165 crew members, according to the CDC.
Explorer of the Seas departed Cape Liberty on January 21 for what would have been a 10-day cruise.
Passengers and crew developed symptoms such as diarrhea and vomiting.
Are cruise ships floating petri dishes?
CDC officials boarded the ship in St. Thomas on Sunday to study the outbreak and the response on the voyage back to Cape Liberty.
The cause of the illness was not clear, though the symptoms are consistent with norovirus, the cruise line said.
Noroviruses spread easily and are a common cause of gastroenteritis, which produces vomiting and diarrhea.
"The number of reported new cases of gastrointestinal illness has dropped sharply after a spike in the first days of the cruise, and most guests who fell ill are up and about," the cruise line said Monday.
"The drop in new cases is encouraging. However, it is not unusual in an outbreak to still have smaller, secondary spikes. That is why, after discussions with the U.S. Centers for Disease Control and Prevention and our medical team, we decided the most prudent course for the health of our guests and crew was to bring the cruise home on Wednesday, two days earlier than planned."
The company said all passengers would get a 50% refund and a 50% credit for a future cruise.
Those passengers who were ordered quarantined to their rooms will get an additional credit of one future cruise day for each day in confinement, it said.
"Guests scheduled for the next cruise on Explorer of the Seas can be confident that all possible measures will have been taken to prevent further problems," it added.
This ship is scheduled to return to its Cape Liberty, New Jersey, port on Wednesday for sanitizing to ensure there are no traces of illness, the liner said in a statement.
The golden-brown color of many soft drinks comes with a dose of the chemical 4-methylimidazole, or 4-MeI. On U.S. product labels it appears simply as "caramel coloring."
Those who say the chemical may possibly cause cancer include the World Health Organization's International Agency for Research on Cancer and the state of California, which now limits manufacturers to 29 micrograms of exposure for the average consumer per day.
Foods exceeding that limit have to carry a warning label that reads: "WARNING: This product contains a chemical known to the State of California to cause cancer."
But when Consumer Reports purchased sodas in California and had them analyzed by a lab, it found that one 12-ounce serving of Pepsi One or Malta Goya exceeded the levels permitted without a warning label.
Ten other brands tested by the group did meet the California standard, which is estimated to limit the risk of cancer from 4-MeI to one case in every 100,000 lifetimes of daily exposure.
"We are concerned about both the levels of 4-MeI we found in many of the soft drinks tested and the variations observed among brands, especially given the widespread consumption of these types of beverages," said Dr. Urvashi Rangan, a Consumer Reports toxicologist, in a statement.
"There is no reason why consumers need to be exposed to this avoidable and unnecessary risk that can stem from coloring food and beverages brown."
The Food and Drug Administration does not set federal limits on 4-MeI in food, and the data gathered by Consumer Reports show that in some cases consumers outside California are drinking a slightly different ingredient. For example, Pepsi One purchased by the group in December in New York contains four times as much 4-MeI as the same product bought that same month in California.
Currently the FDA has no reason to believe that 4-Mel poses a health risk to consumers at the levels found in foods with caramel coloring, agency spokeswoman Juli Putnam told CNN in an e-mail. The government agency is testing a variety of food and beverages with the chemical and reviewing safety data to determine if any regulatory action needs to be taken, she said.
Consumers interested in more information on 4-Mel can check out the FDA's FAQ page.
In a statement to Consumer Reports, PepsiCo Inc. said data indicate that the average person consumes less than one-third a can of diet soda per day; therefore, its product meets the California standard, even if a complete serving exceeds that limit.
In addition to new federal standards, Consumer Reports is calling on the FDA to "require labeling of specific caramel colors in the ingredient lists of food where it is added, so consumers can make informed choices."
"First and foremost, consumers can rest assured that our industry's beverages are safe," the American Beverage Association said in a statement. "Contrary to the conclusions of Consumer Reports, FDA has noted there is no reason at all for any health concerns, a position supported by regulatory agencies around the world.
"However, the companies that make caramel coloring for our members' soft drinks are now producing it to contain less 4-MeI, and nationwide use of this new caramel coloring is underway."