Airline passengers with compromised immune systems, in particular, may want to request canned or bottled beverages and refrain from drinking tea or coffee unless it is made with bottled water.

Results from the latest round of tests, which were performed at airports nationwide in November and December of last year, confirm the presence of bacteria at levels warranting continued scrutiny, according to EPA.

Don't Drink the Water

The information released today is intended to help the public make informed decisions while traveling on aircraft, the agency says. Passengers with compromised immune systems, in particular, may want to request canned or bottled beverages and refrain from drinking tea or coffee unless it is made with bottled water.

Total coliform and E. coli are indicators that other disease-causing organisms (pathogens) may be present in the water and could potentially affect public health, according to EPA. When sampling identified total coliform in the water of a domestic aircraft, that aircraft was disinfected and retested to ensure that the disinfection was effective, the agency notes.

In instances where foreign flag aircraft tested positive for total coliform, those airline companies were notified of the positive test results and advised to disinfect and retest the aircraft.

Two Rounds of Tests

As part of the first round of sampling during August and September 2004, EPA randomly tested the water supplies on 158 aircraft nationwide. Aircraft tank water is used in the galleys and lavatory sinks.

Initial testing of onboard water supplies revealed 20 aircraft (12.7 percent) with positive results for total coliform bacteria, with two of these aircraft also testing positive for E. coli. Following those tests, EPA announced that further testing would take place, and efforts were undertaken to reach agreements with airlines to more closely monitor water quality on planes.

In EPA's second round of water quality sampling, 169 aircraft were tested. The sampling included water from galley water taps as well as lavatory faucets. Testing found that 29 of these aircraft (17.2 percent) were total-coliform-positive. E. coli was not found in the 169 aircraft included in the second round.

Adding together the results of the first and second rounds of testing, EPA tested 327 aircraft in 2004, with approximately 15 percent found to be total-coliform-positive.

Agreements Reached with Airlines

Following the first round of airline water testing in November 2004, EPA announced that agreements had been signed with the following airlines to increase monitoring of water quality testing and disinfecting processes: Alaska Airlines, Aloha Airlines, American Airlines, America West, ATA Airlines, Continental Airlines, Hawaiian Airlines, JetBlue, Midwest Airlines, Northwest Airlines, United Airlines and US Airways.

Two additional airlines, Delta Airlines and Southwest Airlines, are currently negotiating separate agreements with EPA.

Collectively, these 14 carriers represent the majority of U.S. flag carrying aircraft transporting the flying public. The agency will continue to work with smaller, regional and charter aircraft carriers to address drinking water quality with agreements similar to those reached with Air Transport Association (ATA) members. These agreements will govern airline drinking water safety until additional regulations are completed.

EPA began a review of existing safe drinking water guidance to airlines in 2002. In response to the aircraft test results, EPA is conducting a priority review of existing regulations and guidance. The agency is placing specific emphasis on preventive measures, adequate monitoring and sound maintenance practices such as flushing and disinfection of aircraft water systems.

For more information on the regulation of water supplies aboard passenger aircraft and to view publicly available testing data, visit: http://www.epa.gov/airlinewater/ .