VATICAN CITY (AP) — The Vatican Museums chief has warned that dust and polluting agents brought into the Sistine Chapel by thousands of tourists every day risk one day endangering the chapel's masterpieces by Michelangelo.

Vatican Museums chief Antonio Paolucci told the newspaper La Repubblica that in order to preserve Michelangelo's Last Judgment and the other treasures in the Sistine Chapel, new tools to control temperature and humidity must be studied and implemented.

Between 15,000 and 20,000 people a day visit the Sistine Chapel, or some 4 million a year. Paolucci was quoted Thursday as saying that such a crowd "emanates sweat, breath, carbon dioxide, all sorts of dust."

Paolucci said better tools were necessary to avoid "serious damage" to the chapel in the future.