OZONE DEPLETION AND SKIN CANCER

Ozone Depletion and Skin Cancer

Introduction

The ozone layer is part of the Earth's atmosphere that S contains a large amount of ozone. The atmosphere is composed of five layers: troposphere, stratosphere, mesosphere, thermosphere and exosphere. Troposphere, the layer closer to the ground, and where all weather phenomena occur (Diffey 2001). The stratosphere is located directly above the troposphere, about 10-50 km above the planet, and the house of the ozone layer at an altitude of 20-30 kilometers. Mesosphere is located about 50-80 km above the earth, and the thermosphere is at an altitude of about 100-200 km above the Earth. Finally, the boundary of the upper layer, the exosphere, extends to approximately 960-1000 km above the earth.With the ozone layer does?

In the ozone layer, ozone molecules are constantly being violated, to form normal oxygen (O2), as well as reformed by the reaction between oxygen molecules. Reactions in this cycle involve free radicals and, therefore, require ultraviolet (UV) light, and that's how the light is absorbed. The process is called a cycle of ozone-oxygen, and under normal conditions, it absorbs 97-99% of the sun, UV light AO(DeFabo Noonan 2006).

Ozone depletion

Ozone depletion leads to a number of serious risks to human health. This causes more cases of skin cancer and eye cataracts in children are particularly vulnerable. There are also serious consequences for biodiversity (Daynes 2000). Increased UV-B rays reduce the plankton in the ocean, and then the decline of fish stocks. It can also have adverse effects on plant growth, thereby reducing agricultural productivity. Direct negative economic impact is reduced life expectancy of certain materials like plastic.

Studies (Charlson Lovelock et.al 2007) confirm that the vast majority of cells of skin cancers contain mutations that were caused by ultraviolet light. There are two types of ultraviolet light, which is believed to cause skin damage.VA is the radiation wavelength, and a large part of UV radiation arriving at earth's surface. It can penetrate the skin more deeply than UVB, and implicated in premature aging. Until recently it was not believed to cause cell damage, but now known to damage cells in the basal layer of skin (Crombie 2009)

UVB radiation has a shorter wavelength and, although it is much smaller proportion of light reaching the Earth's surface AO is much more damaging to cells. It affects only the outer layers of the skin because it cannot penetrate as far as light UVA, but it causes mutations is much easier, and is responsible for causing sunburn.

Simply put, a tan is part of the body, AO defense mechanisms against cancer. Mutations caused by UV light detected cells, which causes apoptosis (cell suicide). Cells with damaged DNA die, and that is why skin, Äúpeels, Au after combustion. Repeated sunburn can result in some cells that have mutations in their mechanisms of apoptosis, and this may lead to the growth of abnormal cells, causing cancer (Chameides Fehsenfeld et.al2002).Melanoma can also be caused by UV-induced mutations, but it is not associated with repeated cases of ...