Chesapeake Bay Pollution: Impact On Human Health

The Chesapeake Bay is a body of water that has been affected by pollution from a variety of sources, including cars, trucks, power plants, and agricultural activities. This pollution has had a significant impact on both the environment and human health. Excess nutrients, such as nitrogen and phosphorus, have fueled the growth of harmful algae blooms, which block sunlight from reaching underwater grasses and create low-oxygen dead zones that suffocate marine life. These dead zones have detrimental effects on biodiversity and are a constant cause for concern. Additionally, air pollution in the form of nitrogen oxide (NOx) emissions can irritate airways and pose risks to human health, particularly in vulnerable individuals such as children and the elderly. The consumption of fish from the bay may also be unsafe due to high levels of mercury contamination. To protect both the environment and human health, efforts are being made to reduce pollution and enforce air-quality standards.

Air pollution from vehicles and power plants can cause respiratory issues

The Chesapeake Bay is affected by pollution from vehicles, power plants, and other sources. This pollution clouds the air and falls back to Earth, where it can enter waterways, affecting both humans and wildlife.

Air pollution from vehicles and power plants can cause a range of respiratory issues. Vehicle exhaust is a significant contributor to air pollution, and diesel pollution is particularly harmful. Diesel-powered vehicles and heavy equipment release thousands of tons of pollution each year, emitting concentrated air pollution directly into communities. Diesel pollution has been linked to asthma attacks, heart attacks, lung cancer, strokes, and even premature death. It is especially dangerous for children, seniors, workers exposed to it, and people with lung diseases.

Power plants that burn fossil fuels, such as coal, gas, oil, and biomass, emit harmful pollutants that affect lung health. These emissions include sulfur dioxide, nitrogen dioxide, carbon monoxide, and mercury, as well as hazardous pollutants that can cause cancer and other serious health issues. Even biomass plants can produce harmful emissions. The particles released by power plants are tiny and can be blown hundreds of miles, affecting people living near the power plant and those downwind.

The pollutants emitted by vehicles and power plants can irritate the lungs, causing shortness of breath, coughing, wheezing, and chest pain. They also increase the risk of lung cancer, heart attacks, strokes, and respiratory infections. Additionally, people with pre-existing lung diseases, such as asthma or chronic obstructive pulmonary disease (COPD), are more susceptible to the harmful effects of air pollution, experiencing worsened symptoms and increased difficulty breathing.

The impact of air pollution on respiratory health is evident in the Chicagoland area, which continues to violate federal air quality standards due to harmful ozone and particulate matter pollution. Over 70% of Illinois residents live in areas that fail to meet National Ambient Air Quality Standards, and diesel engine exhaust alone led to numerous adverse health events in the state in 2023.

To protect lung health and reduce the impact of air pollution on humans, transitioning to clean, renewable energy sources and electric vehicles is essential.

Water contamination can lead to increased medical costs and lost wages

Water contamination can have a significant impact on human health, leading to various illnesses and diseases. When people consume contaminated water, they are at risk of gastrointestinal illnesses, nervous system disorders, reproductive issues, and chronic diseases such as cancer. The type of contaminant, its concentration in the water, individual susceptibility, the amount consumed, and the duration of exposure all play a role in the specific health effects experienced.

The impact of water contamination on human health is evident in the Chesapeake Bay region, where almost three-quarters of the Bay's tidal waters are impaired by pesticides, pharmaceuticals, metals, and other chemicals. These contaminants can have harmful effects on both humans and wildlife. Additionally, the excess nutrients and sediment in the water contribute to the growth of algae blooms, creating "dead zones" where underwater life cannot survive due to low oxygen levels.

Water contamination can lead to increased medical costs for individuals and communities. When people suffer from waterborne illnesses, they often incur expenses for medical treatment, medication, and hospital stays. In some cases, waterborne diseases can result in long-term health issues or chronic conditions that require ongoing medical care, further increasing medical costs. For example, in rural communities in developing countries, water-borne diseases have been associated with direct medical costs, with individuals spending around US$0.6–1.2 per day on medication.

Moreover, water contamination can also result in lost wages for those who are unable to work due to illness. The indirect costs of waterborne diseases include lost income when individuals are unable to work during their recovery. This loss of income can further exacerbate the financial burden of medical costs, particularly for those in low-income communities. In the case of the Chesapeake Bay, the pollution has led to the death of fish, crabs, oysters, and other aquatic life, affecting the livelihoods of those who depend on these natural resources.

To address the issue of water contamination and its impact on human health, it is crucial to implement effective water treatment and sanitation measures. This includes improving drinking water systems, wastewater treatment facilities, and reducing agricultural runoff. By ensuring access to clean and safe water, communities can reduce the incidence of waterborne diseases and improve overall public health, thereby reducing medical costs and minimizing lost wages due to illness.

Forest loss in the Chesapeake region can contaminate drinking water

Forests are critical to the health of the Chesapeake Bay. They protect clean water and air, provide habitats for wildlife, and support the region's economy. However, human activities have altered the region's forests, reducing tree cover and fragmenting existing forests. Forest loss in the Chesapeake region can contaminate drinking water in several ways.

Firstly, forests act as natural filters, capturing rainfall, trapping polluted runoff, and stabilising soils that could otherwise wash into waterways. Streamside forests, or riparian forest buffers, can reduce nutrient pollution entering waterways by 30 to 90 percent. They also play a crucial role in preventing sediment from turning the water cloudy, which blocks sunlight from reaching aquatic grasses and harms underwater life. Forest loss increases the amount of sediment in the water, endangering species such as oysters and other bottom-dwelling creatures.

Secondly, mature trees have deep root systems that stabilise streambanks and reduce erosion. When forests are lost, the risk of erosion increases, leading to more sediment and pollutants entering drinking water sources. This sedimentation can smother oysters and other bottom-dwelling species, creating "dead zones" where aquatic life cannot survive.

Additionally, forests capture and absorb pollutants from the air, including nitrogen. Streamside forests, in particular, can capture over 85 percent of the nitrogen that falls on them from the air, preventing it from reaching groundwater, rivers, and streams. Forest loss increases the amount of nitrogen that enters drinking water sources, leading to potential health risks for humans. High levels of nitrogen in drinking water sources can contribute to the growth of harmful bacteria, such as Vibrio, which can cause life-threatening skin and blood infections.

Furthermore, the loss of forests in the Chesapeake region can lead to increased water temperatures. Streamside forests shade the water, maintaining cooler temperatures and reducing stress on sensitive fish species. Without this shade, water temperatures can rise, impacting the health of aquatic life and potentially affecting the potability of drinking water sources.

The Chesapeake Bay Program reports that the forests in the watershed protect and filter drinking water for 75 percent of the watershed's residents, approximately 13 million people. However, due to development and other human activities, the region is losing its forests, posing substantial risks to clean drinking water.

Mercury pollution can lead to toxic levels in fish and shellfish

The Chesapeake Bay is impaired by pesticides, pharmaceuticals, metals, and other chemicals, which can harm the health of both humans and wildlife. Mercury is the most common metal found in the watershed. Mercury is a highly toxic chemical, especially to the developing nervous system, and can cause IQ deficits in children. As a result, fetuses, infants, children, and women of childbearing age are at the greatest risk.

Mercury in the Chesapeake Bay comes primarily from air pollution, which is emitted by coal-fired power plants. According to the Environmental Protection Agency (EPA), coal-fired power plants are the largest source of mercury air emissions in the U.S., accounting for more than 40% of the pollution. When coal is burned to generate electricity, mercury is released into the atmosphere and then washed into the Chesapeake Bay and other waterways by rain.

Once mercury enters the water, biological processes can convert it into methylmercury, an extremely toxic form. Plankton absorb methylmercury from the water and sediment, and small fish eat the contaminated plankton. This methylmercury accumulates in the tissues of these fish. Larger fish then eat the contaminated smaller fish, and the methylmercury continues to accumulate as it moves up the food chain.

Humans are at the top of this food chain and are at risk of consuming contaminated fish with high levels of mercury. The amount of mercury in fish tissue can be more than a million times higher than in the surrounding water. Fish and shellfish with higher mercury levels include swordfish and shark. Consumption of fish with high mercury levels can lead to an accumulation of toxic mercury in humans, causing damage to the brain, kidneys, and lungs.

To protect public health, governments in the Chesapeake region have issued fish consumption advisories for mercury for all lakes and rivers in Pennsylvania, Maryland, and many rivers in Virginia. These advisories aim to minimize public exposure to mercury and other contaminants by recommending that certain fish species be limited or avoided altogether, especially for sensitive populations such as pregnant women, nursing mothers, and children.

Climate change impacts, like rising sea levels, threaten human communities

The Chesapeake Bay is affected by pollution from excess nutrients, sediment, chemical contaminants, and invasive species. These issues are caused by agricultural practices, air pollution, and development. The health of the bay is also impacted by climate change, which is causing rising sea levels, warming water temperatures, and prolonged periods of extreme weather.

Rising sea levels due to climate change pose a significant threat to human communities, and their impacts are already being felt in many parts of the world. Here are some of the ways in which rising sea levels threaten human communities:

• More extreme weather and flooding: Sea-level rise increases the risk of extreme weather events such as hurricanes and major storms. When the water levels are already high, storm surges and flooding become more frequent and dangerous. This leads to infrastructure damage, disruption of basic services, and loss of life and property.
• Land loss and coastal erosion: Rising sea levels result in permanent submergence or degradation of land areas. This threatens critical infrastructure such as sewage treatment plants and power stations and leads to economic losses. Coastal erosion is already causing significant property loss, and as sea levels continue to rise, the damage to infrastructure will become more severe.
• Saltwater intrusion and freshwater contamination: Rising sea levels cause saltwater to intrude into inland freshwater sources, such as aquifers and farmland. This contaminates drinking water sources and agricultural land, leading to water insecurity, displacement of communities, and loss of livelihoods.
• Forced migration and displacement: Rising sea levels are causing the displacement of populations on a massive scale. Entire nations, especially small island developing states, are at risk of becoming uninhabitable, leading to a mass exodus of people. This displacement exacerbates social tensions and increases competition for resources.
• Competition over natural resources: As coasts vanish and territories are lost due to rising sea levels, there is increased competition over dwindling resources such as freshwater, land, and food. This competition can lead to conflicts and further instability.
• Legal and human rights implications: Rising sea levels give rise to complex legal questions regarding statehood, sovereignty, maritime boundaries, and the protection of affected populations. The displacement of people due to climate change also raises human rights concerns, including the right to self-determination and the need for innovative legal solutions.

The impacts of rising sea levels are already being felt in many parts of the world, and the consequences are expected to worsen in the coming decades. Addressing this challenge requires urgent and coordinated action by the international community, including reducing greenhouse gas emissions, adapting to changing conditions, and providing support to vulnerable communities.

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