Ozone layer's depletion and environment

by Md. Asadullah Khan


Several factors are responsible for environmental pollution. Chief among these factors are build up of Carbondioxide or other greenhouse gases in the atmosphere, or a host of man-made ills, from toxic wastes to ozone depletion that are causing degradation of the natural environment and the increasing extinction of wild species of plants and animals on this planet earth. People should be allowing more thinking time and greater energy on finding and implementing practical remedial action.For the last three decades scientists and world leaders have been trying to cope with the consequences of exponential growth in human numbers and their increasingly frantic demand for the resources that only nature can provide. They have been working to save the threatened species from extinction and to give the natural process of our world the chance to maintain a healthy global biosphere. This means some sacrifices and restraints and evidently we can no longer pursue short-term prosperity without a thought for long term survival. People in some industrialised countries have mistaken the fact that efforts to achieve conservation of nature threaten human economic welfare. But nations in the present world have hardly any illusion that a good quality of life can only be made up of both material well-being as well as a healthy, productive and beautiful natural environment. And for millions of people like us living in the less prosperous parts of the world, the care and conservation of the natural resources, restraint and cautious disposal of toxic wastes, and hazardous effluents and sludge from the industries is the only way to improve conditions.Looking around, we see that humanity is in conflict with the forces of nature. But the world's biosphere is all that keeps the human species from extinction. That calls for preserving the web of life and any action that we take to exploit it beyond its natural capacity is in every sense a threat to the quality of life of those who will come after us.To help preserve our environment we need to take some urgent and concrete steps like limiting the release of carbondioxide, solving the problem posed by CFCs, cutting pollution and waste that means toughening fuel efficiency standards for autos, launching a large scale tree plantation programme, banning the dumping of wastes by the industrialised countries, making birth control information and devices available to every men and women, developing educational programmes in an effort to impress upon people the value of nature's genetic diversity, promoting waste recycling and encouraging debt for nature swaps.Coming back to the issue of CFCs (chlorofluoro carbons), we see that these CFCs have been linked by scientists to the depletion of the ozone layer which shields the earth from the sun's harmful ultraviolet rays. In deference to the Montreal Protocol timetable, some industrialised countries have already phased out CFCs from their production lines. Assuringly, because of the vigorous R & D (Research and Development) work, development of a washing cum drying method for computer hard disks that replaces CFCs with distilled water and nitrogen in a high speed spin dryer has already reduced the use of CFCs.The second most environmental hazard is pollution largely due to industrial inefficiency, increase in motorised transportation, wasteful consumption and some modern agricultural practice. Humanity has used the world as a waste bin - but the bin is now full and overflowing. Every year 115 million tonnes of sulpher dioxide and around 30 million tonnes of nitrogen oxides are released by the major industrialised nations. One of these results is acid rain which is becoming a major scourge of industrialized nations. These airborne pollutants are no respecters of national boundaries and tackling them successfully relies on international cooperation. Thus air pollution output in the form of acid rain is creeping into developing nations like Bangladesh and India etc. The strange tree disease that is causing extinction of trees in the Sundarbans must be attributed to Acid rain. But these forest resources have to be preserved by all possible means. Nature, it must be stressed here is like business. Business sense dictates that we guard our capital and live from the interests. Nature's capital is the enormous diversity of living things. Without it we can not feed ourselves, cure ourselves or provide industry with the raw materials of wealth creation. Prof. Edward Wilson of Harvard University rightly says, "The folly our descendants are least likely to forgive us is the ongoing loss of genetic and species diversity".So far as it is known, only 150 plant species have ever been widely cultivated. Yet over 75,000 edible plants are known in the wild. In a hungry world with population growing by 90 millions each year, this extinction of plants vastly needed for human survival is tragic. Medicines from the wild, scientists estimate, are worth $ 40 billion a year. Over 5,000 species are known to yield chemicals with cancer fighting potential. But even then the vast majority of species remains unidentified and uninvestigated for its potential usefulness. Scientists currently estimate that the total number of species in the world is between 10 and 30 million - with only around 1.4 million identified. The places that support most diversity are tropical rain forests, mangrove swamps and coastal wet lands. But these are being degraded. Habitat destruction triggers large scale extinction of species. Our Sundarban might come up as a vast trove of medicinal plants that still remain unidentified. It is worth noting that most children with leukaemia now survive by the use of chemicals vincristine and vinblastine donated by the rosy periwinkle. Many people with heart ailment depend on Fox gloves. These flowers provide the digoxin which regulates their heartbeat. Many sufferers from hypertension and high blood pressure get potent relief from the Indian snake root shrub for its reserpine. It is further known that extracts from an Amazonian Oak tree coagulate proteins immensely helping scientists in their search for an AIDS vaccine. Cancer of the lung, kidney and testis responds to Etopaside, a drug sythesised from "May apples". Women who take the contraceptive pill for granted would not be taking it at all were it not for the yam. This large tuber is the source of the pills' active ingredient, diosgenin. Even the healthiest among us take compounds first discovered in fragrant meadowsweet and willow bark and now known a dary movement of hazardous wastes. Unless an understanding of the cross-sectoral linkages among biodiversity, land and water use, sustainable growth, forest management and desertification control is reached on regional basis, our development effort would be set at naught. In recent times, the country's rivers, lakes and wet lands (haors) are a lifeless receptacle of human wastes, pesticide residues and toxic industrial effluents from the dyeing units, textile industries, fertilizer factories, paper and pulp mills and pesticide factories. The poison has seeped so deep that water in the rivers and lakes comes up in hues of green and black. These poisoned water now symbolise not life but death. In consequence, rivers like the Buriganga and Shitalakhya do not have fish of any kind now. Over 300 tanneries in the city's Rayerbazar area discharge chromium-rich effluents that ultimately find their way into the river Buriganga and Sitalakhya. Technology or treatment plants to handle heavy toxic metals like chromium, cadmium and lead have not yet been set up. However, the river water so poisoned is used in different human purposes when the metals are absorbed in the food chain. Cadmium can lead to renal failure; lead can soften bones and other complications. Measures and initiatives to minimize the price man has to pay in the form of disease and death must be taken up without any let up or delay. The country has already encountered the danger of arsenic pollution as a result of excessive use of ground water level and excessive use of chemical fertilizer. All these are telltale indications of our long and dangerous neglect of our environment. Precisely told, the fundamental causes of the country's land and water degradation are need, greed and ignorance. That calls for educating the people that some of our earth or water has been scorched or drained beyond repair and a sustainable development is a must now.


Source: The Independent, November 15, 2000