Wednesday, 16 November 2011 19:44
KARACHI: About three-quarters of the anthropogenic emissions of carbon dioxide to the atmosphere during the past 20 years have been due to fossil-fuel burning. Activities consuming fossil fuels include power generation, industrial and manufacturing processes, and transport. The rest of carbon dioxide emissions are predominantly due to land-use change, especially deforestation.
The main drawback of fossil fuels is pollution. Burning fossil fuel mainly produces carbon dioxide, which contributes to the "greenhouse effect", warming the Earth. It produces more carbon dioxide than burning oil or gas. It also produces sulphur dioxide, a gas that contributes to acid rain. We can reduce this before releasing waste gases into the atmosphere. It is a leading cause of smog, global warming, and air toxics.
Coal is particularly nasty. The attraction to coal is powerful and obvious because Pakistan, being one of the largest coal (lignite) deposits in the world consisting of 184,123 billion tons can produce 1,000,000 MW of electricity for the next three hundred years.
Microscopic particles like sulphates and carbon released from coal-burning power plants and automobiles can reflect sunlight back into space, producing a cooling effect. This can in turn influence global wind circulation patterns that underlie the monsoon system.
One 500 MW power plant generates about 3 million tons of carbon dioxide every year. Other toxic by-products include fine-grain particulates, heavy metals like mercury, lead, chromium and nickel, trace elements such as arsenic and selenium, and various organics like dichloroethane, benzene, carbon tetrachloride, chloroform, and trichloroethylene.
Oxides of nitrogen and sulfur are common pollutants from coal, and are found at higher levels in anthracite than in bituminous coal.
Coal mining produces methane, a potent greenhouse gas. Methane is a naturally occurring product from decay of organic matter as coal deposits are formed with increasing depths of burial, rising temperatures, and rising pressures over geological time. A portion of methane produced is absorbed by coal and later released from coal seam and surrounding disturbed strata during the mining process.
According to Inter-governmental Panel on Climate Change, methane has a global warming potential 21 times greater than that of carbon dioxide on a 100 year timeline. While burning coal in power plants is most harmful to air quality, due to emission of dangerous gases, the process of mining can release pockets of hazardous gases.
WHO estimates more than 2 million people die every year from breathing in tiny particles present in indoor and outdoor air pollution. PM10 particles, which are particles of 10 micrometers or less, which can penetrate into the lungs and may enter the bloodstream, can cause heart disease, lung cancer, asthma, and acute lower respiratory infections.
The WHO air quality guidelines for PM10 is 20 micrograms per cubic metre (µg/m3) as an annual average, but the data released today shows that average PM10 in some cities has reached up to 300 µg/m3.
Burning coal consumption is main reckoning of air pollution this polluted air further causes land pollution and at last mix with water resultant water pollution all different types of pollution impacts negatively on both biotic and abiotic factors, like diseases in all living species and depletion in their number, disturbance of food chain, soil erosion, flooding, and drought, etc.
The Ozone Layer, which is so essential for life on Earth, is unfortunately being depleted due to different kinds of pollutions. The global community especially the developing countries are now facing the challenge of the elimination of Hydro-chlorofluorocarbons (HCFC) in foam and refrigeration industry. It is a second kind of Ozone Depleting Chemical Substance which although has low Ozone Depleting Potential (ODP), yet it possesses high Global Warming Potential (GWP).
The known health consequences of this toxic brew of air and water pollution are many, and include nervous system problems in infants and children, asthma, chronic bronchitis, lung cancer, a suite of cardiovascular problems and kidney disease. The environmental impacts are well documented, and not pretty:
· 3,700,000 tons of carbon dioxide (CO2), the primary human cause of global warming, is responsible for as much carbon dioxide as cutting down 161 million trees.
· 10,000 tons of sulphur dioxide (SO2), which causes acid rain that damages forests, lakes, and buildings, and forms small airborne particles that can penetrate deep into lungs.
· 500 tons of small airborne particles, which can cause chronic bronchitis, aggravated asthma, and premature death, as well as haze obstructing visibility.
· 10,200 tons of nitrogen oxide (NOx), as much as would be emitted by half a million late-model cars. NOx leads to formation of ozone (smog) which inflames the lungs, burning through lung tissue making people more susceptible to respiratory illness.
· 720 tons of carbon monoxide (CO), which causes headaches and place additional stress on people with heart disease.
· 220 tons of hydrocarbons, volatile organic compounds (VOC), which form ozone.
· 170 pounds of mercury, where just 1/70th of a teaspoon deposited on a 25-acre lake can make the fish unsafe to eat.
· 225 pounds of arsenic, which will cause cancer in one out of 100 people who drink water containing 50 parts per billion.
· 114 pounds of lead, 4 pounds of cadmium, other toxic heavy metals and trace amount of uranium.
Pollution from coal mining may have a negative impact on public health in mining communities, according to data analyzed in a West Virginia University research study.
Miners in coal companies are at a higher risk than people living away from mining areas.
According to Hendryx, the main researcher, the data shows that people in coal mining communities have a 70 percent increased risk for developing kidney disease, a 64 percent increased risk for developing chronic obstructive pulmonary disease (COPD) such as emphysema and are 30 percent more likely to report high blood pressure (hypertension).
October is Children’s Health Month, and it is been a good time to focus attention on cleaning up hazards that affect kids more as they grow and develop contributing to the further generation becoming healthy and strong.
Disclaimer: The views expressed by the writer are his own. However, Business Recorder, as a policy, supports coal mining and coal as a source of alternative energy.
Copyright Business Recorder, 2011