WASHINGTON - The U.S. Postal Service is purchasing 1.6 million doses of potassium iodide pills to protect its employees against thyroid cancer in the event of a nuclear explosion or meltdown.

Taking a cue from the anthrax scare a year ago, the postal service is spending nearly $293,000 to give its 750,000 employees the opportunity to have two days' worth of potassium iodide tablets waiting for them at work.

The cost of buying the medication breaks down to 18.3 cents per tablet, bringing the cost of two days of protection to 37 cents per employee, the same as a first-class stamp. The money is coming from the agency's $70 billion budget, which is expected to have a $600 million surplus next year.

"It's an infinitesimal fraction of a percent," postal service spokesman Gerry Kreienkamp said yesterday. "It sounds like a lot of money, but in postal budget terms it's pocket change."

The recommendation to purchase the tablets came from the postal service's mail security task force, created in the month after the anthrax scare. The postal service says the decision is not related to the agency's response to the anthrax scare nor to any threat of nuclear terror specific to the postal service.

Randy Trick is a reporter for the Los Angeles Times, a Tribune Publishing newspaper.