Coal Burning: A Major Contributor To Air Pollution

Burning coal is a major contributor to air pollution, with severe consequences for human health and the environment. Coal-fired power plants emit a range of toxic substances, including mercury, lead, sulfur dioxide, nitrogen oxides, particulates, and other heavy metals. These pollutants are linked to serious health issues such as asthma, cancer, heart and lung diseases, and neurological problems, as well as global warming and acid rain. The release of carbon dioxide, a heat-trapping gas, is a significant driver of climate change, leading to rising temperatures, sea level rise, and increased risks of droughts, heat waves, and species loss. The impact of coal burning extends beyond air pollution, with coal ash contaminating groundwater and posing risks to aquatic life and human health. As a result, burning coal has become an increasingly pressing issue, highlighting the urgent need for a transition to cleaner energy sources.

Coal is a major contributor to climate change and global warming

When coal is burned, its carbon molecules break down, releasing energy. However, other chemical reactions also occur, releasing toxic airborne pollutants and heavy metals into the environment. These emissions include mercury, lead, sulfur dioxide, nitrogen oxides, particulates, and various other heavy metals. These pollutants have severe environmental and public health impacts, including asthma, cancer, heart and lung ailments, neurological problems, acid rain, and global warming.

Coal-fired power plants emit large quantities of small airborne particles, contributing to air pollution and its associated health risks. In 2014, US coal power plants emitted 197,286 tons of small airborne particles (10 micrometers or less in diameter). They also released other harmful pollutants, such as lead, cadmium, carbon monoxide, volatile organic compounds, and arsenic. These emissions can have detrimental effects on human health, including respiratory illnesses, cardiovascular issues, and increased risk of cancer.

Coal is a significant contributor to global warming, primarily due to the carbon dioxide (CO2) emissions released during combustion. CO2 is a heat-trapping gas that accumulates in the atmosphere, acting like a blanket and warming the Earth's surface. The consequences of global warming driven by CO2 emissions include rising temperatures, accelerating sea level rise, increased frequency and intensity of extreme weather events, and species loss. In 2022, CO2 emissions from burning coal for energy accounted for about 19% of total US energy-related CO2 emissions and 55% of CO2 emissions from the electric power sector.

Coal mining practices can also contribute to climate change and global warming. Mountaintop removal and valley fill mining, commonly used in the Appalachian Mountains, involve removing mountain tops with explosives, altering the landscape. The water draining from these filled valleys can contain pollutants that harm aquatic wildlife downstream. Additionally, coalbed methane emissions from active and abandoned mines contribute to greenhouse gas emissions, further exacerbating global warming.

Coal releases toxic mercury into the environment

Burning coal releases toxic mercury into the environment, which has been linked to a range of serious health issues. Mercury is a naturally occurring element found in the earth's crust, but when it is brought above ground, it can be harmful due to its neurotoxicity. All forms of mercury can be toxic, but methylmercury is the most concerning as it can more easily pass through the body's blood-brain barrier and the placental barrier in pregnant women. Exposure to methylmercury has been associated with neurocognitive deficits, and the epidemiological literature shows that these issues can persist into adulthood. Additionally, exposure to mercury during adulthood is linked to problems with fine motor function, verbal memory, and cardiovascular disease.

Mercury is released into the atmosphere when coal and other fossil fuels are burned. Once airborne, mercury can stay in the atmosphere for over a year and travel to remote ecosystems, especially those in the Arctic Circle. It then contaminates the land, oceans, and streams, where it is converted into methylmercury, which can accumulate in our food and, eventually, in us. Methylmercury enters the food chain, particularly in aquatic organisms, and bioaccumulates. This means that the substance becomes more concentrated in an organism, including through additional uptake via the food chain. Cases of mercury poisoning have been documented in people who eat contaminated fish for prolonged periods, both in the United States and abroad.

Coal-fired power plants are the largest source of mercury emissions, with coal plants responsible for 42% of mercury emissions in the United States. In 2017, coal-fired power plants emitted approximately 8,800 pounds of mercury. The combustion of coal releases mercury, which, along with other heavy metals, has been linked to neurological and developmental damage in humans and other animals.

To reduce mercury emissions, several options have been proposed, including selective mining of coal by avoiding parts of a coal bed that are higher in mercury content, coal washing to reduce mercury content, switching from coal to natural gas, and post-combustion removal of mercury from power plant stack emissions. The Mercury and Air Toxics Standards (MATS) have also been implemented to set limits on mercury emissions, resulting in a 90% decrease in mercury pollution from coal-fired power plants over a decade. Despite these efforts, stronger safeguards are still needed to protect the health of those living near power plants, who are disproportionately affected by mercury pollution.

Coal ash contaminates water sources

The burning of coal has long been a reliable source of energy for the US, but it comes with tremendous environmental and health costs. One of the most significant impacts of coal combustion is the contamination of water sources by coal ash.

Coal ash, also known as coal combustion residuals (CCR), is a byproduct of burning coal in coal-fired power plants. It contains toxic contaminants such as mercury, cadmium, arsenic, and other heavy metals. These contaminants can leach into the groundwater and surface water, posing a significant threat to both ecosystems and drinking water sources. According to the US Environmental Protection Agency (EPA), 94% of coal ash ponds in the US are unlined, allowing coal ash to come into direct contact with groundwater. This results in the contamination of private drinking water wells, putting nearby communities at risk of exposure to harmful toxins.

The contamination of water sources by coal ash has been documented at numerous sites across the US. For example, the New Castle Generating Station near Pittsburgh was found to be heavily contaminated with arsenic and other toxic chemicals. Similarly, at least 26 sites have been identified where private wells have been contaminated by coal ash, with many more likely going undetected due to a lack of testing and the colourless, tasteless nature of coal ash pollutants.

The EPA has recognized the urgency of addressing coal ash contamination and is taking steps to hold facilities accountable for controlling and cleaning up the pollution. However, progress has been slow, and many contaminated plants have neither committed to a cleanup plan nor accepted responsibility for the contamination.

The issue of coal ash contamination underscores the environmental and public health consequences of burning coal. As the US continues to rely on coal as a significant energy source, it is crucial to address the safe disposal and management of coal ash to mitigate its impact on water sources and the health of communities.

Coal emissions cause respiratory illnesses

Burning coal releases a number of airborne toxins and pollutants, which have been linked to respiratory illnesses. These include:

• Mercury, a toxic heavy metal that can damage the nervous, digestive, and immune systems, and is a serious threat to child development.
• Sulfur dioxide, which contributes to acid rain and respiratory illnesses.
• Nitrogen oxides, which contribute to smog and respiratory illnesses.
• Particulates, which are known as "soot," and are linked to chronic bronchitis, aggravated asthma, cardiovascular effects like heart attacks, and premature death.
• Volatile organic compounds (VOCs), which form ozone and contribute to smog.
• Arsenic, which causes cancer.
• Carbon monoxide, which causes headaches and places additional stress on those with heart disease.

These emissions have severe health impacts on miners, workers, and surrounding communities. In 2013, 366,000 deaths in China were attributed to coal, and in the United States, coal-related deaths are recorded at 50,000 each year, with air pollution from coal-fired power plants contributing to leading causes of mortality, including heart disease, cancer, stroke, and chronic respiratory diseases.

The health impacts of coal emissions are wide-ranging, from asthma and breathing difficulties to brain damage, heart problems, cancer, neurological disorders, and premature death. The economic and health costs associated with burning fossil fuels are significant, and without them, average life expectancy would increase by more than a year.

To protect public health and reduce the burden on healthcare services, it is essential to transition to cleaner sources of energy and implement effective pollution controls to minimize emissions from coal-fired power plants.

Coal mining changes the landscape and harms wildlife

Another environmental impact of coal mining is acid mine drainage (AMD), which occurs when water reacts with sulfur-bearing minerals in rocks, resulting in highly acidic water containing toxic heavy metals. AMD poses a severe threat to wildlife and renders affected waterways unusable for drinking and recreation. In some areas, the water flowing from coal mines is so acidic that it can burn the skin. This problem is particularly prevalent in central Appalachia, where many streams are tainted with orange, acidic water. AMD degrades approximately 12,400 miles of rivers and streams in the US, posing health risks to ecosystems and nearby communities.

Surface mining, also known as strip mining, involves using large machines to remove layers of soil and rock to expose underground coal deposits. This process often requires clearing forests and stripping away the earth, leading to deforestation and displacement or death of wildlife. Without vegetation to anchor the soil, precipitation can cause erosion, with loose topsoil being carried into nearby waterways.

Underground mines generally have a less significant impact on the landscape, but they are not without their risks. The ground above mine tunnels can collapse, and acidic water can drain from abandoned mines. Additionally, methane gas, which occurs in coal deposits, can explode if it becomes concentrated in underground mines. While some mines capture and use or sell the coalbed methane, it must be vented to make the mines safer. In 2021, methane emissions from coal mines accounted for about 7% of total US methane emissions and 1% of US greenhouse gas emissions.

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