On Tuesday the euro will replace the national currencies of 12 European Union countries. The United Nations Children's Fund says the changeover to the euro could be a bonanza for its efforts to provide life-saving materials and services for needy children around the world.

UNICEF runs a global program with 13 airlines called Change for Good. Since 1991, it has raised more than $31 million from spare coins and paper currency collected from passengers on international flights. UNICEF fundraiser Della Weight says the Euro provides a special opportunity.

"We are certainly working in each of our national offices in ways in which to collect those coins and even notes that are going to be useless to people in the future," she explaind. "So of course with the introduction of the euro, a lot of those programs are doing special promotions, if you like, to encourage people not only to give foreign coins, but the European currencies that will go out of circulation."

UNICEF estimates that every year $72 million in foreign coins and low denomination bills are forfeited by international air passengers who take them home and put them in a dresser drawer. Ms. Weight says this unwanted foreign change can yield tens of millions of dollars a year and help save lives.

She says the airlines are pleased to participate in the program for its "feel-good" factor and the way it improves their international image. Ms. Weight says an in-flight video or audio announcement informs passengers about the collection.

"And then small collection envelopes are either placed in your headset [package] if it is a long-haul flight or perhaps in your seat-back pocket. ... It is almost like a door-to-door collection, but seat-to-seat on the plane," she said.

Ms. Weight says the foreign change pays for life-saving needs for children in 160 countries. It helps provide clean water, vaccines, healthcare and school supplies.

She says two dollars in foreign coins could buy 40 oral re-hydration packets, a lifesaving mixture of salt and sugar that prevents death from diarrhea. The same two dollars could buy 66 pencils for schoolchildren, or enough high-dose Vitamin-A to protect 57 toddlers for one year against disease and blindness.