Hazard of Coal and Coal Mining to Human Health Essay

Custom Student Mr. Teacher ENG 1001-04 29 December 2016

Hazard of Coal and Coal Mining to Human Health

Coal is a solid but brittle sedimentary rock with a natural brown to black color and is made up of carbon, hydrogen, oxygen, nitrogen, and lesser amounts o f sulphur and trace elements. Coal is classified into four types depending on the carbo n, oxygen and hydrogen content on which the higher the carbon content, the more energy the coal contains (Coal at a Glance, 2009). The amount of energy in coal is define d by the heat value measured by British thermal units (Btu). One Btu is equivalent to the amount of energy in a single match (RockTalk, 2005). The four types of coal include lignite, sub bituminous, bituminous, and anthracite. The lowest rank of the coal i s lignite and has a heating value of 4,000 to 8,300 British thermal units (Btu) per pound.

This type is the softest with high moisture content, least amount of carbon a nd is mainly used to produce electricity. The second least of the four types is sub-bituminous coal with a heating value of 8,300 to 13,000 Btu per pound and contains 35 to 45 percent carbon. After addition of more heat and pressure on lignite, bituminous coal is formed which is made of many tiny layers. It contains 11,000 to 15,500 Btu per pound heating value and is an important fuel for the steel and iron industries. Of the commonly minable coals, anthracite is the hardest and has a heating value of 15,000 Btu per p ound containing 86 to 97 percent carbon (Coal at a Glance, 2009).

Coal is a non-renewable source of energy because it takes million of years to form. It has become a powerhouse by the 1800’s in America in which the people used coal to manufacture goods and to power steamships and railroad engines . It was noted that after the American Civil war, coal was used to make iron and steel and by the end of 1800’s, people used coal to make electricity. In the 1900’s, coal is the mainstay for the nation’s business and industries. Coal stayed America’s number one energy source until petroleum was used for petroleum products that became a demand. In 2009, 93.6 percent of all the coal in the United States was used for electricity production.

Coal generates almost half of the electricity used in the U.S (Coal at a Glance, 2009). Based from Gree n World Investor (2011), coal has numerous uses primarily as a source of fuel and as a rich carbon source. It also plays an important role in cement and steel industries and coal is the largest source of electricity production. Coal is mainly used as fuel to generate electricity t hrough combustion. In steel production, coal together with iron, are the two raw materials used to produce steel in which the former is used as a fuel to smelt the iron in furnace until the cast iron is further refined. Similar with electricity and cement production, coal is also being used as a fuel in cement industry. Furthermore, paper a nd aluminum industry also uses coal as a fuel since coal is cheap and very available for these types of industries that are huge consumers of energy fuel.

According to World Coal Association (2012), “the biggest market for coal is Asia, which currently accounts for over 65% of global coal consumption; although China is responsible for a significant proportion of this. Many countries do not have n atural energy resources sufficient to cover their energy needs, and therefore need to import energy to help meet their requirements. Japan, Chinese Taipei and Korea, for example, import significant quantities of steam coal for electricity generation and co king coal for steel production”. They also added that coal users further include alumina refineries and chemical and pharmaceutical industries. Chemical products can be produced from the by-products of coal. Refined coal tar is used in the manufacture of c hemicals, such as creosote oil, naphthalene, phenol, and benzene.

Despite the myriad benefits coal has to offer, t here is always a disadvantage of using it. According to Fossil Fuel Resources (2012), coal burning causes the emission of harmful waste such as carbon dioxide, sulphur dioxide, nitrogen oxides, sulphuric acids, arsenic and ash. Furthermore, coal emits twice as much carbon dioxide compared to natural gas in producing the same level of heat which increases the level of emission of greenhouses ga ses into the earth’s atmosphere. As well as large factories and power industry that burn coal causes acid rain in some areas. Moreover, coal mining damages t he landscape a nd the environment as a whole plus t he large and noisy equipment used for mining may a ffect local wildlife.

Transportation of coal can also be a problem since it requires extensive transportation system and causes additional pollution from vehicle emissions. Another huge disadvantage is that the coal is a non-renewable energy source and thi s millennium, coal can be depleted if burning of coal is continued in the future. Likewise, in coal mining industry, health difficulties of miners occur and fatalities due to dangerous nature of work increase. This paper would be tackling about the Health Hazard that is imposed otherwise could be caused by coal and coal mi ning. However, it is important to understand the impact of this activity to economy and environment, which could help in knowing the impact to health t hus socioeconomic and environmental effects of coal mining are at the same time discussed.

Developing co untries seek to exploit mineral resources to provide needed revenue thus, mineral wealth is a part of some nation’s natural capital (Davis and Tilton, 2003). However, Sideri and Johns (1990) stated that mineral development does not always boost a country’s economic growth and in some cases contribute to increased poverty. Some of the contributing factors for this misfortune were low level of employment, institutional corruption and mismanagement (Sideri and Johns, 1990). Coal industry development may result in national economic growth however, the benefits are not equally shared, causing local communities nearest to the mining site suffer the most. Miranda et. al (1998) added that mining as a general triggers negative impacts such as alcoholism, prostitution a nd sexually transmitted disease.

According to Dr. Michael Hendryx (2009), “Areas with especially heavy mining have the highest unemployment rates in the region contrary to the common perception that mining contributes to overall employment”. S ynapse Energy Economics (2009) added, referring to Appalachia where mountaintop removal for coal mining is being done, “History shows that the transition from deep to surface mining devastated the region economically, and that the prosperity of mining companies has not gone hand in hand with the economi c welfare of coal mine workers. Appalachia has suffered from current and persistent economic di stress, and that this distress has been associated with employment in the mining industry, particularly coal mining.” Mountaintop removal coal mining remove the miner from the process, replacing manpower with machinery, and lowering the coal companies’ overhead cost (Appalachian Voices, 2012).

From the article “Mortality in Appalachian Coal Mining Regions: The Value of Statistical Life Lost” authored by Michael Hendryx and Melissa M. Ahern (2009), it was stated that the Appalachian region of the United States has long been associated with severe socioeconomic disadvantages. These results to a poor public health comprising elevated morbidity and mortality rates for a variety of serious, chronic conditions, such as diabetes, heart disease, and some forms of cancer. Furthermore, recent studies have confirmed that health discrepancies exist in coal mining regions of Appalachia compared with other areas of the region or the nation . These discrepancies include elevated mortality rates for total causes, lung cancer, and some chronic illnesses.

It was noted that t hese studies showed that mortality is related to higher poverty, lower educati on levels, and smoking behavior, and further s uggested that environmental pollution from the mining industry is a contributing factor. In the study of Paul Younger (2004) , “Environmental impacts of coal mining and associated wastes: a geochemical perspec tive”, it was stated that in the early years of coal mining, impact on the environment adversely affect long -established agricultural interests. The negative impacts of coal mining came to be accepted as a by-product of the generation of coal-based wealth d uring the time when coal trade dominate regional economies in mining districts. These negative impacts became unacceptable when large-scale mining began and took place in major coal-mining economies. It was further stated in the study that t he environmental impacts of coal mining are results of the exposure of reduced earth materials that involves coal and others, to the oxidizing power of the Earth’s atmosphere. The study recognize subcategories of impacts under five major headings consisting of air pollu tion, fire hazards, ground deformation, water pollution and water resource depletion.

Production of large quantities of waste is one major environmental issue that can be caused by coal mining. The impacts are more widespread in open-casts compared to underground mining, which produces less waste. Severe impacts could cause degradation of aquatic and marine resources and causes water quality reduction. According to Johnson (1997), erosion after heavy rainfall pushes waste rock piles and runoffs to nearby waste bodies and sometimes, this lead to disruption, diversion, and changing of slope and bank stability of stream channel and t hese disturbances significantly reduces the water quality. Ripley (1996) added that higher sediment concentrations increase the t urbidity of natural waters which lowers the available light to aquatic plant for photosynthesis. Elimination of important food source and decreased available habitat for fish to migrate and spawn usually happens if there is increased sediment loads that s uffocate organisms in marine organisms (Johnson, 1997). Furthermore, higher sediments decrease the depth of water bodies which could contribute to flood (Mason, 1997).

Deforestation is also a major indirect environmental impact of coal mining especially i n opencast or surface mining. Biodiversity is greatly affected , more importantly the removal of vegetation that alters the shelter and the availability of food for the wildlife. Coal mining also poses an environmental alarm in wetlands such as estuaries, mangroves and floodplains that actually served as natural filters of pollution as well as provide habitat for aquatic organisms. These areas are destroyed through direct habitat elimination or pollution from washable coals that were washed to produc e a clean pure coal (H.A. Mooney et al, 1995).

Mining activities in general has many environmental impacts but at the same time, poses a significant risk to human health. The health cost of mining operations most of the time outweighs the advantages gaine d ( Yeboah, J.Y, 2008). Possible hazard including diseases or illnesses acquired from coal mining is discussed below as summary of various studies and articles about health risks caused by exposure to coal and coal mining.

The association of pneumoconiosi s and other respiratory health risks with exposure to respirable mixed dust was identified in the study of Love R.G, Miller B.G.,

6 The Hazards of Coal and Coal Mining to Human Health et. al. (1997), entitled “Respiratory health effects of opencast coalmining: a cross sectional study of current workers” conducted in United Kingdom opencast coal mines. The study carried out 1,224 men and 25 women at nine large and medium sized opencast sites in England, Scotland and Wales. Full sized chest radiographs, respiratory symptoms, occupational history questionnaires, and simple spirometry were used in the study to characterize the respiratory health of the workforce. In addition, logistic or multiple regression techniques were utilized to examine relations between indices of exposure and respiratory health.

The study c oncluded that the frequency of (mostly mild) chest radiographic abnormalities is associated with working in the dustier, preproduction jobs in the coal mining industry. Although some of these mild abnormalities may be non -occupational (due to aging or smok ing), the association with exposure indicates a small risk of pneumoconiosis in these men, and the need to monitor and control exposures, particularly in the high-risk occupations. This study of respiratory health effects of opencast coal mining seems unalarming and maybe controlled since it was indicated that there is a small risk of pneumoconiosis among miners, however, coal mining effects to humans are not just limited to respiratory health. Furthermore, there are various studies that could prove that co al mining or coal combustion is a great contributing factor of respiratory illnesses most especially black lung disease.

The negative impact of coal mining pollution to public health is analyzed in a study in West Virginia. Michael Hendryx and Melissa Ahern (2008) used the data from a 2001 research survey correlated with data from West Virginia Geological and economic survey showing volume of coal production from mining. Hendryx and Ahern study was “Relations between Health Indicators and Residential Proximity to Coal Mining in West Virginia” which have examined the coal mining in West Virginia if it is related to poorer health status and incidence of chronic illness. The study used data from a survey of 16, 493 West Virginians merged with county- level coal production and other covariates in investigating the relations between health indicators and residential proximity to coal mining.

The research sought to find whether the effects of coal mining may result only from socioeconomic factors such as inco me and education problems together with environmental exposure problems or it a lso a ffects the health aspect of the people. It was emphasized that quantitative research on health consequences of residential proximity to coal mining is limited to a few stud ies of respiratory illness, which was conducted in Great Britain. With t hese few studies, one showed no effect of coal mining but there are studies t hat found increased risks. These were the main reason why this study was conducted. The result of the study showed that “As coal production increased, health status worsened, and rates of cardiopulmonary disease, lung disease, cardiovascular disease, diabetes, and kidney disease increased. Within larger disease categories, specific types of disease associated with coal production included chronic obstructive pulmonary disease (COPD), black lung disease, and hypertension.”

The research found t hat the result of black lung disease is higher in men compared to women since this condition affects miner’s which are men. The risks for coal -associated illnesses increase with exposure to coal by-products. Toxins and impurities in coal cause kidney disease, hypertension and other cardiovascular disease. The effects also resulted from the general inflammatory or systemic consequences of inhaled particles and these effects may be multi -factorial, a result of slurry holdings that leach toxins into drinking water and air pollution effects of coal mining and washing. This study served as a screening test to examine whether co al mining poses a health risk for adults living near the mining site. The researcher recommended that confirmatory tests should be undertaken to establish mechanism of action, magnitude, and health consequences of an exposure effect.

Another study of health hazard brought by coal mining is “The association between mountaintop mining and birth defects among live births in ce ntral Appalachia, 1996–2003”, a research study authored by Melissa Ahern et. al.(2011). This study examined birth defects in mountaintop coal mining areas compared to other coal mining areas and in non-mining areas of central A ppalachia. The researchers aimed to know if higher birth-defect rates are present in mountaintop mining areas . Moreover, this study analyzed 1996-2003 live births i n four Central Appalachian states using natality files from National Center for Health Statistics.

It was stated from the study that “The prevalence rate ratio (PRR) for any birth defect was significantly higher in mountaintop m ining areas compared to n on-mining areas, but was not higher in the non m ountaintop mining areas, after controlling for covariates. Rates were significantly higher in m ountain top m ining areas for six of seventy types of defects: circulatory/ respiratory, central nervous system, m usculoskeletal, gastrointestinal, urogenital, and ‘other’.” It was found out that mountaintop- mining effects became more pronounced in the latter years (2000–2003) versus earlier years (1996–1999.). Furthermore, it was mentioned that the elevated birth defect rates are partly a function of socioeconomic disadvantage, but remain elevated after controlling for those risks. They also added that both socioeconomic and e nvironmenta l inf luences in mountaintop mining areas maybe contributing factors.

In a researc h article authored by Hans L. Falk and William Jurgelski, Jr., “Health Effects of Coal Mining and Combustion: Carcinogens and Cofactors”, carcinogens and cofactors that may be present in coal is being tackled. As an epidemiologic evidence of carcinogenic risks in coal mining and combustion, it was mentioned that several epidemiological studies imply that the incidence of gastric carcinoma in coal miners is elevated above that of comparable segments of the general population not engaged in mining of coal.

On t he other hand, the article noted that death rate of coal miners from lung cancer is appreciably lower than the rate for non-miners of comparable age. It was explained that the data obtained from various studies about lower rate of lung cancer among coal miners strongly suggest that an unknown factor probably coal dust, exerts a protective effect from acquiring cancer. It was further noted that even though the coal dust is beneficial with regard to lung cancer, it is the causative factor of black lung disease. Therefore, while lung cancer rates might not increase as a result of an expansion of coal production, black lung and other respiratory diseases would probably become more prevalent.

Health effect of exposure to respirable coal mine dust according to Center for Disease and Control Prevention includes Black Lung Disease or Coal Worker’s Pneumocosis (CWP), silicosis, mixed -dust pneumoconiosis and Chronic Obstructive Pulmonary Disease (COPD). CWP was defined as a chronic dust disease of the lung and its sequelae, including respiratory and pulmonary impairments, arising out of coal mine employment. It was moreover defined as parenchymal lung disease produced by deposits of coal dust in the lung and the response of the host to the retained dust. The primary lesion of CWP is like that of silicosis however, the amount and nature of dust and quantity and disposition of fibrous tissue and the presence of emphysema differs. Coal macules are rounded, irregular and ranges from 1 to 5 millimeters, lesions are distributed symmetrically found in both lungs with a greater concentration in the upper lobes (Attfield and Wagner, 1992).

The proportion of dust, cellular material, or collagen varies depending on the rank of coal dust inhaled (Cotes and Steel, 1987). Silicosis develops when respirable silica inhaled is deposited in the lungs and varies from chronic, complicated, accelerated, or acute. Third is mixed -dust pneumoconiosis, which describes pulmonary lesions where crystalline silica is deposited combined with less fibrogenic dusts as iron oxides, kaolin, mica and coal (Silicosis and Silicate Disease Comittee, 1988). Chronic Obstructive Pulmonary Disease (COPD) refers to three disease processes which involve chronic bronchitis, emphysema, and asthma which are all characterized by airway dysfunction (Barnhart, 1994). COPD is mainly caused by cigarette smoking nevertheless, it could also be caused by air pollution and exposure to dust. Chronic bronchitis is associated with airflow obstruction and abnormalities in gas exchange (Barnhart, 1994).

Coal dust and its sequelae are not the only health hazards of coal mining. Common occupational hazards brought by mining are also applied in mining coal. According to Institute for Occupational and Safety Development (2006), “M ining poses tremendous risks to life and limb, not only to miners but to community as well ”.

Hazardous mining operations caused both directly and indirectly countless accident. Hazards presented by mining to workers include intense exposure to heat, poor ventilation, fumes, repetitive stress injury, intense noise, manual handling of heavy machinery aside from biological and chemical hazard.

Miner’s tend to have fluid and salt deficiency due to constant sweating since hydration is very limited combined with inte nse heat especially in underground mining sites. Furthermore, miners could have increased heart stress, heat stroke, and fertility reduction due to high temperature. Poor ventilation on the other hand, steals the oxygen from the body which results to brain malfunction and this can lead to death. Vibration from handling or operating large machines could result to permanent bone damage and vibration syndrome or dead finger syndrome that could proceed to hand and finger gangrene. The constant shaking could als o progressed to digestive problems because of constant moving of internal organs. Hearing impairment or disruption of body functions such as blood circulation and hormone imbalance could be a result of noise and hazardous sound that comes from drilling, blasting among others. Manual lifting of materials can cause back troubles leading to acute pain.

Based from the government statistics, a ccidents in the industry of mining was used to be 0.1% in the year 2000 of the total occupational accidents however in 2 002 it increased to 1.7% of the total accidents which is in fact only 0.3% of the total labor force was into mining and this poses a very dangerous trend for mining ( IODC, 2006). Hazards mentioned above are, of course, i nevitable due to the nature of the activity itself. Yet, there are still other ways for them, in a way, to minimize the occurrence of these while working. In line with this is the importance of risk management.

To be aware of the Risk Management is very important most espe cially when involving to activities that could pose risk not only to one ’s heal th but also to emotional, psychosocial, economical and e nvironmental aspect of an individual. Risk management is mainly the identification, assessment and prioritizations of threats brought about the actions going through or have gone through already. Through this method, t he pros and cons o f the action to be considered could be weighed. In t his discussion paper, certain risks that should have been given much attention b y the implementers of coal mining are tackled.

From the hazards mentioned above, risk management that could minimize the impact includes the following assessment. There should have been even just an exhaust fan or some opening that some air could enter for them to be able to breathe as normally as possible. Also, to be able to minimize cases of deafness, miners are advised to wear ear plugs when heavy equipment is be i ng operated. Through this, noise could be minimized. It will also be advisable for the miners to have a sufficient supply of water with them as they progress with their work. Proper hydration is very much essential for them because there is poor ventilation inside the mine. The beverage they have with them should contain electrolytes for them to minimize incidence of fluid and salt deficiencies.

An excerpt taken from t he article of Institute of Occupational Health and Safety Development s tates that, “Mines exposes workers to different types of airborne particulates, making them vulnerable to systemic toxic effects due to the absorption of coal dus t. Coupled with poor ventilation, this can trigger accidents and cause death to workers. RSI being a soft -issue disorder is caused by overloading of particular muscle group from repetitive use or maintenance of constrained postures. Miners who suffer from RSI complain of weakness of the affected muscles, heaviness, “pins and needles” sensation and numbness.”

In this hazard, miners are expected to have protective masks that cou ld keep them from inhaling coal dust. Without the masks, this makes them very much vulnerable, primarily, to respiratory diseases and to other health -related illnesses. Presence of openings within the mines should also be considered for them to be able to breathe normally as possible.

According to an article posted on www.greatmining.com, “Coal dust settles like pollen over the surrounding areas.” As what we ha ve discussed o n our Environmental Health class this s ummer, coal dust measures above 100µm. Thus, it could only irritate the mucous membranes of the eyes, nose and throat but not going further . Yet, considering that there is an occurence of anthracosis, which is detect ed primarily in the lungs. There is a contradiction between this standard measurement and association and the chemical effect of the inhalation of coal dust.

According to a study conducted by Sapko,M. J, et. al, “Particle size can vary both within and between mines, since size is dependent on several factors such as mine type (i.e., longwall or continuous miner, along with cutting speed and depth) and coal seam type. In addition to total incombustible content and methane concentration, the coal dust particle size should be considered as an essential part of the explosibility assessment strategy in underground coal mines.“

Coal mining creates several billion gallons of coal slurry, which contains extremely high levels of mercury, cadmium, and nickel. Although lauded by mining companies that this is a safer, more efficient way to produce coal, this type of strip mining has evoked strong protests from environmentalists and people who reside near coal mining areas. Coal mining work can be extremely dangerous, a s the numerous occupational hazards can cause critical injuries or even death. Since coal is also a necessity in our day to day lives, there is no way to be able to totally terminate or stop the operations of coal mining. All we could do is to minimize the risks that could threaten us if we are to put up or be involved in coal mining.

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13 The Hazards of Coal and Coal Mining to Human Health

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