VATICAN CITY (CNS) — Going on vacation must not be an occasion to relax one's commitment to saving energy and protecting the environment, the Vatican said.

Tourism can have “a serious environmental impact owing, among other factors, to the immoderate consumption of energy resources” and an increase in pollution and waste, said a message from the Pontifical Council for Migrants and Travelers.

The message, released by the Vatican July 25, was written in preparation for the observance Sept. 27 of World Tourism Day, an event promoted by the United Nations World Tourism Organization and supported by the Vatican.

The theme for the day is “Tourism & Sustainable Energy: Powering Sustainable Development.”

While acknowledging that people are becoming more aware of their responsibility to care for the earth, the message said it is also true that people risk setting aside their ecological sensitivities while on vacation “in a search for certain comforts to which we believe we are entitled, without always reflecting on their consequences.”

“It is necessary to cultivate the ethics of responsibility and prudence and to ask ourselves about the impact and consequences of our actions,” the message said.

The pontifical council noted the importance of tourism for global economic health and development, saying the World Tourism Organization estimates that 1 billion people will travel internationally in 2012 and that the number of international travelers is likely to double by 2030.

With so many people on the move around the globe, the council said, each tourist must show concern for his or her impact on the environment and on the earth's future.

The Vatican office called for support of tourist programs that are energy efficient, have the least environmental impact possible and favor the use of renewable energy sources.

“In this regard, it is fundamental for the ecclesial tourism structures and vacation proposals promoted by the church to be characterized, among other things, by their respect for the environment,” it said.