Mario Molina

In 1973 Mario Molina was a postdoctoral researcher working in the laboratory of F. Sherwood Rowland at the University of California at Irvine, just south of Los Angeles, when he made an unsettling discovery. He had been investigating a class of compounds called chlorofluorocarbons, or CFCs. CFCs were used as refrigerants, aerosol sprays, and in making plastic foams. Molina wondered what happened to them once they were released into the atmosphere.

This was a hypothetical study, but his results showed disturbingly that CFCs could, in theory, destroy a compound called ozone under the conditions that exist in the upper atmosphere. Far above the earth's surface, a thin layer of ozone floats, protecting us from the sun's ultraviolet radiation. Molina, just a young scientist at the time, was nervous about showing Rowland his theory of how CFCs might destroy ozone. But if CFCs really could wipe out ozone, the whole world would be in trouble.

Rowland took his protogé seriously. Over the next two decades he and Molina became voices crying in the wilderness, alerting the world to the danger of CFCs and ozone depletion. They weren't always heeded. Bans on CFCs in aerosol sprays went into effect first in the United States in 1978, and later in Canada, Norway, and Sweden. CFC use for other purposes only increased. Scientists, activists, politicians, and CFC-producing companies would argue for years over the merit of Molina's theories.

Mario Molina was born in Mexico City, where Mario's father was a successful lawyer and a diplomat. As a child, Mario was fascinated with chemistry and converted one of the bathrooms in his family's house to a chemistry laboratory for himself. His aunt, Esther Molina, was a chemist, and she encouraged and mentored the boy by helping him carry out more advanced experiments than normally possible with a child's chemistry set. Recognizing his passion for science, Mario's parents sent him to a boarding school in Europe, where they thought his fascination with science would be nurtured.

Mario returned to Mexico City for college, and earned an undergraduate degree in chemical engineering from the Universidad Nacional Autonoma de Mexico in Mexico City. He continued to have difficulty finding friends who shared his passion for science. After graduation, the young Molina studied at universities in Germany and France, but those studies did not provide the intellectual satisfaction he was seeking.

Molina speaking at a     meeting of the ACS.

Finally, Molina was accepted for graduate study at the University of California at Berkeley, and his life changed. There he began to find his place in science and in life. After earning his PhD Molina made his way to UC Irvine where he joined Sherwood Rowland's group as a postdoctoral researcher. It was then that Molina and Rowland began wondering what might be happening to CFCs released into the atmosphere.

As time went on, Molina moved on from UC Irvine to work at NASA's Jet Propulsion Laboratory where he continued to investigate ozone depletion. Over the years, evidence mounted in support of Molina's theories, leading to increased international regulation of CFCs. But this did not happen easily, nor did it happen overnight. As we'll see, it took a near disaster before most of the world would listen to Molina. But in the end, he would be vindicated, and in 1996 he was awarded the Nobel Prize for Chemistry, along with his old boss Rowland and Swedish scientist Paul Crutzen for the work they had done in helping unravel the mysteries and dangers of CFCs.

Today Molina continues his research of gas-phase chemistry, including the effects of pollutants in the atmosphere at the Massachusetts Institute of Technology. Not forgetting his roots, he has also been involved in studying ways of making the air in cities cleaner, looking for strategies to reduce urban air pollution. Mexico City has been the case study for this project. We hope that Molina's methods will help alleviate the choking pollution of his old hometown.

Next: Ozone Issue Basics

Mario J. Molina: Institute Professor — learn about Dr. Molina's work firsthand from his own Web site at the Massachusetts Institute of Technology.

Nobel Poster in Chemistry 1995 — featuring the science and autobiographies of Paul Crutzen, Mario Molina and F. Sherwood Rowland, from the Nobel Foundation.