According to a study, it is estimated that the Montreal Protocol, an international initiative to preserve the ozone layer, could prevent 443 million cases of skin cancer and 63 million cases of cataracts in the United States. The research was carried out by scientists from the National Center for Atmospheric Research (NCAR), ICF Consulting and the U.S. Environmental Protection Agency (EPA).
In this context, the treaty has prevented 99 percent of potential health impacts from ozone depletion. With the most recent change to the Protocol, approximately 2.3 million skin cancer deaths in the U.S. are avoided.
Using a computer simulation, the treaty’s impact on a projection of Americans born between 1890 and 2100 was analyzed. The model showed the effects of the Montreal Protocol on the ozone layer, which represents a reduction in ultraviolet (UV) radiation that is beneficial to health.
It also showed an increase in skin cancer and cataracts that started with the depletion of the ozone layer. The peak was found in the population born between 1950 and 2000, having been exposed to the highest radiation levels.
The ozonosphere protects life within the planet by serving as a shield against harmful levels of UV radiation from the Sun. In 1987 the Montreal Protocol was signed, which condemned the use of chemicals that deplete the ozone layer and consequently threaten health.
In the 1970s, the ozone layer was threatened by chlorofluorocarbons used in refrigerants and other utensils. These compounds released chlorine atoms into the ozonosphere and, in turn, triggered a chemical reaction that destroyed ozone.
Over the years, the treaty has been amended to protect the ozone layer further. For this reason, the use of various chemicals, such as halon and hydrochlorofluorocarbons, has been banned or reduced.
To quantify the importance of the treaty, a group of scientists developed a model known as the Atmospheric and Health Effects Framework. It shows past and future emissions of ozone-depleting substances and is updated annually by the EPA.
According to the study, loss of the ozone layer would be catastrophic for human health. High levels of UV radiation have been linked to certain types of cancer, cataracts and immune diseases. For these reasons, it is crucial to join efforts to preserve its conservation.