Emergency preparedness officials are preparing to distribute more than 1 million potassium iodide tablets in the 10-mile emergency planning zone around the Millstone Power Station over the next few months.

The pills, which protect the thyroid from absorption of radioactive iodine isotopes that can be released after a severe nuclear power plant accident, are distributed in the nine-town region around the Waterford plant periodically. Two batches of pills supplied to the region in 2007 will expire in February and April, Neil Sheehan, spokesman for the Nuclear Regulatory Commission, said Monday. They are commonly known as KI pills, for the periodic table symbols for the two main ingredients.

The NRC will send 1.28 million 65-mg tablets to the state Department of Emergency Services and Public Protection in the coming months, he said. Adults would take two pills, while each child under 100 pounds would take one. Taking the pills in the immediate aftermath of a nuclear accident would reduce the likelihood of developing thyroid cancer. The pills are intended to supplement the sheltering and evacuation of populations around a nuclear plant if there were an accident, Sheehan said.

The pill distribution would be handled by the emergency management directors in each of the towns in the emergency planning zone: East Lyme, Groton, New London, Waterford, Ledyard, Lyme, Montville and Old Lyme and Fishers Island, N.Y. It is expected to take place sometime before the end of this year.

Scott DeVico, spokesman for the state Department of Emergency Services and Public Protection, said the state will stockpile a small number of the pills, but most will be given to the towns to distribute to their residents. Households would receive two pills for each adult and one for each child.

"As soon as we get the supply from the NRC, we'll put the plan in motion," he said.

Joe Sastre, emergency management director for Groton, said the distribution would be done in a method similar to the one used in 2007. Due to the cost, they would not be mailed except in cases of those who are homebound, he said.

The pills would be made available at the town and city police departments, where residents could stop in any time and ask for them, Sastre said. His office is preparing a public information campaign to get the word out through various media outlets before the distribution.

"We're really going to emphasize that the best use of the KI pills is with young people, because older folks have a reduced risk of contracting thyroid cancer," he said.

In addition to making the pills available to households, the towns will also supply large quantities to local colleges, schools, child care centers, nursing homes and major employers, Sastre said.

Richard Morris, emergency management director for East Lyme, said his office will recommend that residents keep their KI pills in a "to-go bag" of emergency supplies they would take with them if they had to evacuate their homes quickly. The bags should contain such items as a flashlight, batteries, water, non-perishable food, maps and medications. East Lyme residents will be invited through the town website, Facebook and public announcements to go to the town hall to get their new KI pills, he said.

The pills were mailed to residents in 2003, but the state changed to in-person distribution in 2007 for several reasons, DeVico said. In addition to mailing costs, he said, "there was a perception about some safety issues with mailing white pills."

"And face-to-face distribution is preferred, so members of the public can receive some verbal instructions at the same time," DeVico said.

j.benson@theday.com