Only three of the 11 major airlines sampled were found to serve water safe enough to drink

Water on Most U.S. Airlines Is Unsafe, Says Study: Avoid Coffee, Tea and Even Washing Your Hands

It may be time to rethink how you hydrate in the sky.

A new study has found that many of the U.S.’s most popular airlines do not provide safe drinking water — and it may actually be making passengers sick.

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The 2019 Airline Water Study conducted by DietDetective.com and the Hunter College NYC Food Policy Center investigated 11 major airlines and 12 regional airlines, scoring them from 0 to 5 (5 being the best) on the quality of water they provide onboard. The scores were based on 10 criteria, including airline fleet size; the presence of coliform bacteria or E. coli in the water; and the amount of times they’ve violated the federal government’s Aircraft Drinking Water Rule (ADWR), which was implemented in 2011 and requires airlines to provide safe drinking water to all passengers and staff.

Study scores of 3 or higher suggest the water on board is safe enough to drink — startlingly, only three of the 11 major airlines sampled achieved this score, along with just one of the 12 regional airlines.

“Alaska Airlines and Allegiant win the top spot with the safest water in the sky, and Hawaiian Airlines finishes No. 2,” said Charles Platkin, PhD, JD, MPH, the executive director of the Hunter College NYC Food Policy Center, in a press release. Alaska Airlines and Allegiant Air both received a 3.3, while Hawaiian Airlines was given a 3.1.

Spirit and JetBlue tied for the lowest score of the major airlines, each receiving a 1 out of 5.

Piedmont Airlines was the highest-rated regional carrier with a score of 4.33, while the lowest score, 0.44, was given to Republic Airways, which operates United Express, Delta Connection and American Eagle flights.

In order to protect yourself from potential pathogens, DietDetective.com and the Hunter College NYC Food Policy Center suggest never drinking water served on a plane unless it is bottled and sealed.

This includes coffee or tea served on board.

They also suggest not washing your hands in the aircraft bathroom, and instead bringing along your own hand sanitizer.

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The study warns that airlines with poor scores may have E. coli present in their water, so there is potential for disease-causing bacteria to be ingested by passengers and staff. They suggest this may be due to the varying sources from which planes get their water.

“An aircraft flies to numerous destinations and may pump drinking water into its tanks from various sources at domestic and international locations,” according to the study. “The water quality onboard also depends on the safety of the equipment used to transfer the water, such as water cabinets, trucks, carts and hoses.”