The UN is announcing an International Year of Sanitation Wednesday in an effort to warn of problems encountered by 2.6 billion people worldwide who have no proper sanitation facilities.

Each year, an estimated 1.5 million children die because of lack of access to water, sanitation and proper hygiene. Women and girls are vulnerable to violence at night when they are forced to search for sanitation.

UN Secretary General Ban Ki-moon and Prince Willem-Alexander of the Netherlands are launching the international year for 2008 at UN headquarters to put the global crisis of sanitation on the forefront of the international agenda, the UN said. Willem-Alexander is chairing a UN advisory board on water and sanitation.

'Clean, safe and dignified toilet and hand-washing facilities in schools help ensure that girls get the education they need and deserve,' said Ann Veneman, the executive director of the UN Children's Fund.

Of the estimated 2.6 billion people without proper sanitation, 980 million are children.

The UN has called for the investment of $10 billion a year in order to halve the number of people without sanitation by 2015. It said if the investment is sustained over a period of time, proper sanitation could be provided to the entire world within one or two decades.