The Department of Homeland Security is screening passengers and cargo entering the United States from Japan for "even a blip of radiation," Homeland Security Secretary Janet Napolitano said Thursday.
Customs and Border Protection said there have been reports of radiation being detected from some cargo arriving from Japan at several airports. Those airports include Chicago, Dallas and Seattle. Radiation has not been detected in passengers or luggage. And none of the reported incidents involved dangerous or harmful amounts of radiation.
The agency handles more than half a million radiation alarms a year, though many are related to medical procedures.
No harmful levels of radiation have reached the U.S. since the nuclear crisis in Japan sparked by last week's devastating earthquake and tsunami, she said.
CBP, which monitors ports, routinely screens passengers and cargo for radiation. Agents have been advised this week to pay particular attention to arrivals from Japan.
Napolitano said the screening of passengers and cargo is being done "in an exercise of caution."