OZONE DEPLETION, A HARBINGER OF HEALTH

Ozone depletion, a harbinger of health

Dr. Dwijesh Kumar Panda, M.D., Ph.D, Senior Scientist.

What is Ozone: -

The element oxygen exists naturally in two forms. The more abundant form has two atoms of oxygen joined together to form a molecule. This is the oxygen breathe. Sunlight keeps breaking the O2 molecule into two oxygen atoms. These atoms can rejoin to form oxygen or join another oxygen molecule and make O3 or Ozone. Almost 90% of Ozone in the atmosphere is concentrated in the stratosphere – the layer of the atmosphere between about 10 and 50 km altitude. It acts like Sunscreen lotion and absorbs a large proportion of the Sun’s ultraviolet (UV) radiation which would otherwise sterilize earth and eliminate life from the planet. It absorbs the most energetic UV-c and UV-b radiation and filters about half of the UV-a radiation. Exposure to these can cause sunburn, lead to Cancer and damage eyes.

Why is it getting depleted? 

There are many naturally occurring substances that can destroy ozone. For instance, ozone gets destroyed when it comes in contact with molecules that contain nitrogen, hydrogen, chlorine, bromine and so on. In the atmosphere, oxygen and ozone molecules are continuously converting into each other and a balance is maintained. But of increasing man made pollution and the release of gases like CFCs (chlorofluorocarbons) the natural balance is broken and the amount of ozone destroyed is far higher than the amount naturally formed.

What is the ozone hole?

There is nothing like a continuous layer of ozone in the atmosphere and a hole in that coating. Ozone does not form any layer. It is dispersed in the atmosphere like other gases. But the zone of atmosphere where ozone has maximum density is called the ozone layer. The density of ozone is measured by Dobson units. The average amount of ozone in the atmosphere is about 300 Dobson units. If all this ozone is compressed at zero degrees Celsius at one atmospheric pressure it would form a 3 mm thick layer around the earth. What we call ozone holes are the areas where the concentration drops to an average of about 100 Dobson units. 100 chemicals are being phased out for ozone.

Initiatives to check the depletion:

A 1986 NASA study found the depletion of ozone over Antarctica. Human pollution results in ozone depletion It was also established that CFCs (chlorofluoro carbons) were the main catalyst in ozone’s destruction. The first measure global initiative to restrict CFCs was taken when the Montreal Protocol was signed in 1987. The protocol requires the control of nearly 100 chemicals. For instance, hydro chlorofluorocarbons (HCFCs) are to be phased out by 2030 in the developed world and 2040 in the developing world. By these initiatives the depletion which had stretched up to an area of 26 million square km in 1998 was reduced to 22 million square km in 2009. The presence of harmful chemicals around the clouds accelerates the degradation of ozone. West polluted and we are paying. The developed countries that have overused the atmospheric carbon sink help developing nations build infrastructure for alternate sources of fuel that do not result in carbon emissions.

Health hazards:-

The Sun can nourish or destroy our body by UV radiation. The sun’s ultraviolet rays are torpedoed down to earth. The UVC rays are blocked by the atmosphere, so they have little effect on us. The rays that are constantly being played into our body are the UVA rays and the UVB rays. If the UVB rays are stopped at the level of the skin, they can still cause burning and cancer of the skin and tanning as well. Moreover, if the UVA rays penetrate deep in to the skin they cause burns, wrinkles, and skin cancer. To top it up, sunlight also destroys the reserves of folic acid, also known as folate or vitamin B9. Folate is needed so our body can replicate DNA properly (that is why it helps protect against birth defects). Also the rays can damage our eyes.

How do UV rays cause damage?

One of the ways that the rays cause damage is through the connective tissue breakdown. UV radiation causes the structural protein of our skin, collagen to break down and disable our ability to repair damage. Another way the sun ages our skin is through the formation of free radicals- those aggressive charged compounds that damage cells break down collagen as well. Free radicals can cause cancer by changing our DNA and preventing our body from repairing it. How? UV destroys the rungs of the DNA ladder so that the DNA ladder posts bind with one another. This makes a bulge so that the DNA does not form or function correctly. Still another way that the UV rays cause damage is by thinning the walls of surface of blood vessels, leading to bruising, bleeding, and showing the appearance of blood vessels through the skin. The Major Ager of UV radiation has a great impact on our eyes by oxidizing the pigments in the retina and decreasing the antioxidants in the thin, yellowish film that protects it: meaning that these delicate cells are always at the risk of being damaged through another Major Ager, free radicals. Sunlight damage to the eye is cumulative-particularly in conditions like macular degeneration, where the cells die from oxidative damage. Radiation from the Sun that passes through the ozone stimulates our eyes (Visible rays) and our skin (UV rays). The UV wavelengths either bounce off the dermis or penetrate deeply into our tissues like the depletion of folate.

Protection against Ultra Violet Radiation:

The Environmental Protection Agency (EPA) has cautioned people to protect themselves against UV light 'whenever you can see your shadow'. Some of the common preventive measures that need to be followed are to avoid overexposure to sunlight especially between 10 am to 4 pm when the UV rays are at their strongest. It is advisable to make sure to be adequately protected by wearing the appropriate clothing and protective covering like hats whenever exposed to the sun. Make sure to carry an umbrella when going out. One must ensure to apply a generous coating of appropriate sunscreen suitable for the skin type after consulting a dermatologist. Sunscreen Lotions are available in different SPFs like 15, 30, etc. One should always avoid artificial means of tanning, such as the use of sun-tan beds. In case of blisters due to overexposure, the neighborhood GP or dermatologist should be consulted for right diagnosis and treatment so that the condition does not worsen.

 

The End.

                                                                                            Dr. Dwijesh Kumar Panda, M.D, PhD.

                                                                                            Senior Scientist, Govt. Of Orissa.

                                                                                             M5/12, Acharya Vihar,

Bhubaneswar-751 013

                                                                                                   Contact- +919438470777.

Submitted to the Director, NISER, Bhubaneswar, Orissa, Institute of Physics Campus, Bhubaneswar, 751005. Email: tkc@niser.ac.in for favour of publication in Souvenir, UNESCO Kalinga Prize for popularization of science.

How Safe is Your Cell Phone?

How Safe is Your Cell Phone ?

Cell phones emit electromagnetic radiation, exposure to which may cause brain cancer, especially children and pregnant women should keep the device away from the head and body. But it is worth noting that both the National Cancer Institute and the World Health Organisation say there is no evidence to support the assertion that cell phones are a public health threat. But a number of scientists are worried that there has been a dangerous rush to declare cell phones safe using studies they feel are inadequate and too often weighed towards the wireless industry’s interests. An analysis published by University of Washington neurologist Henry Lai determined that far more inadequate studies than industry funded studies have found at least some type of biological effect from the cell phone exposure.

          Several countries- including Finland, Israel and France- have issued guidelines for cell-phone use with 270 million Americans and 4 billion people around the world using cell phones and more signing up every day – a strong link between mobiles and cancer could have major public-health implications. As cell phones make and take calls, they emit low-level radio-frequency (RF) radiation. Stronger than F.M. radio signals, these RF waves are still a billionth the intensity of known carcinogenic radiation like X-ray.

The wireless industry contends that RF radiation lacks the strength to alter molecules in the human body; the Federal Communication Commission (FCC) is intended to prevent RF radiation from heating tissue to the point that cells are damaged. Cell phone RF radiation’s “effect on the body, appears to be insufficient to produce genetic damage typically associated with developing cancer.”

         But the body of research is far from conclusive. In 1995, Lai co-wrote a study showing that a single two-hour exposure of RF radiation- at levels considered safe by U.S. standards- produced the sort of genetic damage in rat’s brain cells that can lead to cancer. Though subsequent researchers-often funded in part by the wireless industry- failed to replicate Lai’s results, a 2004 European Union–funded study reported similar findings.

          The scientific consensus is that cell phones have not yet been shown to pose a risk to human health, but that further research is necessary. Government have imposed safety guide-lines on manufacturers, based on the amount of radiation absorbed by the brain in normal cell phone use, but a level of uncertainty about the risks remains. The long term effects of cell phone use will not be known for certain for a number of years. In the short term, therefore, it seems wise to take steps to minimize one’s exposure to cell phone radiation, but without falling into hysteria.

          The main cause of concern to do with the safety of cell phone use is the level of radiation emitted by the cell phones. Cell phones are the sources of radiation and in ordinary use are held in close proximity to the head. A proportion of this radiation- between 10% and 50%, depending on the cell phone in question, the position in which it held, and several other factors- is absorbed by the brain. Those who wish to minimize the risks that they run in using their cell phones therefore need to do two things: minimize the radiation emitted by their cell phones and minimize the proportion of that radiation that they absorb.

          The U.S. Food and Drug administration raised concerns about a heightened risk of brain cancer. The Swedish researchers continue to monitor the possible health problems stemming from exposure to radio frequency energy. Those who heavily used wireless phones had a 240 percent increased risk of cell phone cancer or a cancerous tumor on the side of the head where they used their phone. Study finds High cell phone cancer risk from cell radiation. According to a Swedish study released recently, the use of mobile phones over a long period of time can raise the risk brain tumors-contradicting the conclusions of other researchers.

50 cities to get mobile kit to trace radiation

Fifty cities across the country will soon have Mobile Radiation Detection Systems (MRDS) as part of the preparedness to handle radiological emergencies. Confirming the government’s moves, M. Sashidhara Reddy, Vice Chairman of the National Disaster Management Authority (NDMA), said radiation cannot be seen, heard or smelt which makes it difficult for the regular law enforcement agency to detect it. It is proposed to equip Police Vehicles in the selected Police Stations in Major cities with simple radiation monitoring Go/No-Go type survey instruments. It will help the staff in locating the presence of radioactive material in the surrounding area. There is very strict compliance with prescribed safety standards at all nuclear installations, the main concern today should be the use of large number of radiological material, in the fields of medicine, agriculture, industry, research and even in many commonly used appliances.

The End