FIVE AMERICAN Airlines workers have accused the airline of using watercooler jugs to carry chemicals aboard planes to decontaminate lavatories - and then returning the jugs to commercial circulation to be refilled with drinking water and redistributed.

In a lawsuit filed Monday in Philadelphia Common Pleas Court, the workers say the practice - known as "top-filling" - began in 2010 after the airline took over cleaning its own lavatories from an outside contractor.

Normally, workers attach hoses from lavatory trucks on the tarmac to a parked plane's underbelly to pump toilet waste down into a container on the trucks, according to the lawsuit. They then use another hose to pump deodorant cleaning concentrate, known as "blue juice," from the trucks into the plane lavatories.

But the intake mechanism on many Boeing 757s, a model last produced in 2004, has broken or malfunctioned, according to attorney Brian Mildenberg, who filed the lawsuit.

Rather than repair the faulty parts, supervisors have directed workers to pour the blue juice into empty, five-gallon Deer Park jugs, carry them into the planes and then dump the juice into toilets by hand, said Trandom Millsip, one of the lawsuit's plaintiffs and a fleet service agent who has done lavatory-cleaning duties for the past year and a half.

Afterward, workers are directed to return the jugs to the employee break rooms where they got them, Millsip said. The practice leaves dangerous dregs in the jugs, which workers don't clean, Millsip added.

The bottles then are picked up by unsuspecting Deer Park workers for refilling, he said. When he complained to supervisors about it, Millsip said, they threatened to discipline him.

"It's a wrong practice all the way around," said Millsip, 30, of Southwest Philly.

The lawsuit, which alleges a public nuisance, fraud and conspiracy, names American Airlines, US Airways (which recently merged with American) and nine airline officials as defendants.

It seeks an injunction for the airline to cease operations until the top-filling practice ends and asks the court to appoint an investigator and overseer to ensure compliance.

An American Airlines spokesman suggested the complaint was nothing more than a grudge by an overzealous attorney.

"Mr. Mildenberg has brought several lawsuits against the company over the years that we found to be frivolous and that were ultimately dismissed," American Airlines spokesman Matt Miller said. "But we, of course, take any allegations surrounding our employees and customer service very seriously and will fully investigate these latest accusations. We are proud of our 8,300 PHL-based employees and are 100 percent committed to serving the citizens of Philadelphia."

Mildenberg represents nearly 100 American Airlines and US Airways workers here and in Washington, D.C., who asked the U.S. Justice Department in July to investigate their claims that bosses routinely use racial slurs, deny minority workers perks and training, delay or botch maintenance and repairs, keep dangerously faulty equipment in use and retaliate against complainers.

Mildenberg also sued US Airways on behalf of the NAACP in 2010 alleging discrimination against minority employees at the Philly airport. That case resulted in a confidential settlement and the airline's promise to strengthen workplace diversity and training.

In response to Miller's comment, Mildenberg said: "The evidence in this case speaks for itself. Their response is an attempt by wrongdoers to cover their tracks."

Nestle Waters North America representative Tom Uhl said his company is aware of the lawsuit and is "thoroughly investigating the allegations."

"If the allegations are true, it's unacceptable," said Uhl, vice president of Quality Assurance for Nestle, which distributes Deer Park water.

"Our number one priority is the health and safety of our customers and the quality of our products," he said. "We have industry-leading product safety measures in place to ensure our bottled water meets or exceeds all regulatory requirements.

"While we have complete confidence in our quality processes and the products we produce, as a precautionary measure, we are taking steps to ensure that no bottles from this customer are reused until this is resolved."

Pope Francis is flying on American this week: The Vatican chartered a Boeing 777-200 from the Fort Worth, Texas-based airline to ferry Francis to New York yesterday, Philly tomorrow and back to Rome on Sunday, Miller said.

On Twitter: @DanaDiFilippo

Blog: phillyconfidential.com