The effect of ozone depletion on human health has been a major focus of scientists since the concern about the damage to the ozone layer was first given international prominence in 1972.

In March 1977, the "World Plan of Action on the Ozone Layer" was adopted under the auspices of the United Nations Environmental Programme (UNEP). This plan called for, amongst other things, research into the effect of ozone depletion on human health.

Owing to increasing concern over the continuing depletion of the ozone layer and its possible long-term consequences to all forms of life, the "Vienna Convention for the Protection of the Ozone Layer" was adopted by the international community in March 1985. This was followed in September 1987 with agreement on specific measures to be taken to arrest the decline under the "Montreal Protocol on Substances that Deplete the Ozone Layer."

Since 1997 several reports have been presented by international scientists on the effects of ozone depletion on human health. The consensus is that depletion of the ozone layer leads to significant increases in ultra-violet-B radiation (UV-B) reaching the Earth's surface. This excessive UV-B is responsible for a wide range of potentially damaging human and animal health effects, primarily related to skin, eyes and immune system.

Small quantities of ultraviolet-B radiation (UV-B) are essential to human health, acting as a catalyst in the generation of vitamin D. However, large amounts of UV-B are harmful to a wide range of biological systems. One of the deleterious effects of UV-B on human beings is related to prolonged, deliberate , as well as inadvertent sunlight exposure, which leads to the development of non-melanoma skin cancer and malignant melanoma of the skin. This is particularly applicable to fair-skinned persons who sunburn easily and who receive prolonged occupational or recreational exposure. Studies have shown that in Europe persons who are now age 30 have a higher incidence of melanoma than persons at age 30, ten years earlier. It is estimated that a one-percent decrease in stratospheric ozone will result in a three-percent increase in non-melanoma skin cancer, and a lower but sill significant increase in melanoma.

Another deleterious effect of UV-B is damage to both the cornea and lens of the eye. The initial response of the eye to exposure to UV-B radiation is the condition termed photokeratitis in which the front of the eye, the eyelids and the skin surrounding the eyes become reddened.

Cataract, a disease of the lens is the most prevalent form of ocular damage associated with UV exposure. Corrective surgery can prevent most cataracts from causing blindness. However, in the United States, cataract remains the third leading cause of legal blindness. In developing countries, where the percentage of the World aged population is greatest and where such operations are not always available, cataracts result in a much higher incidence of blindness and can become a major public health problem. It has been estimated that a one-percent decrease in stratospheric ozone will be accompanied by a 0.6 to 0.8 percent increase in cataracts.

Ultraviolet radiation is known to affect the immunological defenses of the skin. The skin often is the first point of contact with many foreign substances (antigens) including infectious agents. In these instances, the skin's immune response is the body's first line of defense. Preliminary experiments of infectious diseases using animal models have indicated that UV-B can also adversely affect the ability of animals to respond to or contain various infectious agents. Although there are as yet no epidemiological data to suggest that such effects occur in human populations, nevertheless, animal data suggest that an increase in the severity of certain infections may occur as UV-B increases due to ozone depletion. In areas of the world where such infections already pose a significant challenge to the public health care delivery systems, the added effect due to ozone depletion may be significant.

Trinidad and Tobago as a signatory to the Montreal Protocol for the Protection f the Ozone Layer, is determined and committed to doing its part to reduce and ultimately eliminate the use of ozone depleting substances (ODS).

To this end, the country has targeted the air-conditioning sector in tits efforts to reduce Chlorofluoro-carbons (CFCs), an ozone depleting substance.

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