A US college student imprisoned for three weeks for trying to take flour-filled condoms onto an airplane has settled her lawsuit against Philadelphia for $US180,000, a city spokesman said today.

Janet Lee, 21, a student at Bryn Mawr College in Pennsylvania, was arrested at Philadelphia International Airport in 2003 after police and security officials thought the flour was an illegal drug.

She was held in Philadelphia on drug-trafficking charges and released only when tests proved the substance in the three condoms was flour.

The condoms, which are sometimes used to smuggle drugs, were a joke among the students, and Lee was taking them home to Los Angeles.

Her civil rights case against Philadelphia, which had been set to go to trial on Thursday before it was settled, said Ted Qualli, spokesman for Philadelphia Mayor John Street.