Molina, Mario (1943– )

Mexican chemist who shared the Nobel Prize for Chemistry in 1995 with Paul Crutzen and F Sherwood Rowland for their work in atmospheric chemistry, particularly concerning the formation and decomposition of ozone. They explained the chemical reactions that are destroying the ozone layer.

The power of nitrogen oxides to decompose ozone was pointed out in 1970 by Crutzen. In 1974 Rowland and Molina published a widely read article on the threat to the ozone layer posed by chlorofluorocarbons (CFCs) used in refrigerators and aerosol cans. They pointed out that CFCs could gradually be carried up into the ozone layer. Here, under the influence of intense ultraviolet light, the CFCs would decompose into their constituents, notably chlorine atoms which decompose ozone in similar ways to nitrogen oxides. They calculated that if the use of CFCs continued at an unaltered rate the ozone layer would be seriously depleted after a few decades. Molina's and Rowland's work led to restrictions on CFC use in the late 1970s and early 1980s.

Molina was born in Mexico City and educated in physical chemistry at the University of California, Berkeley, USA. The first Mexican to receive a Nobel Prize for science, he announced in February 1996 that he would donate part of his prize to fund the training of environmental researchers from Latin America and other developing countries. Molina is currently at the Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.