Mechanics inspected the plane overnight and cleaned air vents and changed filters in the rear, said spokesman Paul McElroy. But, he said, "We don't know the cause. We're still monitoring" the plane.
It is back in service, he said.
Fight 137 carried 141 passengers and five crew members. It left Portland at 5:49 p.m. and arrived in Anchorage at 8:42 p.m. It was met by several ambulances and emergency vehicles.
Paramedics checked out a handful of passengers from the back rows but found no one else with symptoms, McElroy said.
The two flight attendants were taken to the hospital and released, McElroy said.
Reach Rosemary Shinohara at rshinohara@adn.com or 257-4340.
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