Study reveals which airlines have the most contaminated water

Water for onboard coffee comes from tanks that may be infected with bacteria, despite airlines required to flush and disinfect them four times a year - (Getty Images/iStockphoto)

Flight attendants often post on social media to warn passengers against drinking the onboard coffee, claiming it’s made with water that isn’t clean enough.

A recent study supports their stance and identifies the U.S. airlines most likely to carry potentially unsafe water: passengers on American Airlines, JetBlue, and multiple regional airlines should be most wary, according to the research.