Human Impact: The Root Of Pollution

Pollution is the introduction of harmful materials into the environment. These harmful materials, called pollutants, can be released into the atmosphere as gases, finely divided solids, or finely dispersed liquid aerosols. Air pollution is a major threat to global health and prosperity, causing more than 6.5 million deaths each year worldwide. It is caused by a combination of human-made and natural sources. Human-made sources include vehicle emissions, fuel oils, and natural gases used to heat homes, as well as by-products of manufacturing and power generation. Natural sources include wildfires, volcanic eruptions, and gases emitted from decomposing organic matter. Water pollution, caused by untreated sewage and agricultural runoff, also poses significant risks to human health and the environment.

Burning fossil fuels

The burning of fossil fuels has increased steadily since the invention of the first coal-fired steam engines in the 1700s. Today, we burn over 4,000 times more fossil fuels annually than we did in 1776. Fossil fuel combustion is a significant contributor to global air pollution, with fossil fuel-related pollution causing one in five deaths globally. In the United States alone, 350,000 premature deaths in 2018 were attributed to fossil fuel-related pollution, with certain states, such as Pennsylvania, Ohio, and West Virginia, having the highest number of deaths per capita.

The health impacts of air pollution from burning fossil fuels are extensive. Short-term effects include irritation to the eyes and throat and damage to the lungs, especially in children, senior citizens, and people with pre-existing respiratory conditions such as asthma. Long-term exposure to air pollution has been linked to various diseases, including lung cancer, colorectal cancer, prostate cancer, heart disease, and premature death. A large-scale study of over 57,000 women found that living near major roadways may increase the risk of breast cancer. Additionally, prenatal exposure to air pollution has been associated with an increased risk of cerebral palsy and neurobehavioral problems in children, such as attention-deficit/hyperactivity disorder (ADHD) symptoms.

In addition to air pollution, burning fossil fuels also contributes to water pollution and plastic pollution. Power plants that burn fossil fuels use large amounts of freshwater for cooling, which can cause stress for local species when the warm water is returned to nearby ecosystems. Oil spills and fracking fluids can contaminate groundwater and drinking water with toxic substances such as arsenic, lead, chlorine, and mercury. Furthermore, over 99% of plastics are made from fossil fuels, and plastic waste ends up in our oceans, killing wildlife and polluting the food chain.

The combustion of fossil fuels has significant environmental and social impacts, contributing to climate change, extreme weather events, and global inequality. It is essential to recognize the disproportionate burden faced by vulnerable communities, including children, the poor, and minorities, who are more vulnerable to the health and economic consequences of toxic air pollutants and climate change. Addressing the burning of fossil fuels and transitioning to more sustainable energy sources are crucial for protecting the health and well-being of current and future generations.

Vehicle emissions

According to the National Institute of Environmental Health Sciences, vehicle emissions are a primary source of human-made air pollution. The burning of gasoline and diesel fuel in internal combustion engines releases harmful by-products, including nitrogen dioxide, carbon monoxide, hydrocarbons, and formaldehyde. Additionally, vehicles emit carbon dioxide (CO2), the most common human-caused greenhouse gas, which contributes to global warming and climate change. The average passenger vehicle emits about 4.6 metric tons of CO2 per year, and each gallon of gasoline burned releases approximately 20 pounds of CO2 into the atmosphere.

The type of vehicle and its fuel economy also influence emission levels. For example, the popularity of gas-guzzling SUVs and pickup trucks with poor mileage counteracts the progress made by more fuel-efficient modern vehicles. Electric vehicles (EVs) are a cleaner alternative, producing zero tailpipe emissions. However, they still contribute a small amount of greenhouse gas emissions due to air conditioner leakage. Hybrid vehicles, which use both electricity and gasoline, have more complex emission calculations that depend on their specific operating modes.

To reduce vehicle emissions, individuals can choose to drive more fuel-efficient vehicles, maintain proper tire inflation, and adopt driving practices that reduce fuel consumption, such as observing speed limits and accelerating gradually. Additionally, opting for alternative transportation methods like walking, biking, or using public transportation can significantly decrease vehicle emissions and improve air quality.

Industrial processes

The burning of fossil fuels, such as coal and petroleum, in factories and power plants, contributes significantly to air pollution. This process releases hazardous substances, including greenhouse gases like carbon dioxide and methane, which enhance the greenhouse effect and contribute to global warming. Additionally, the fumes released from chemical production and the by-products of manufacturing further exacerbate air pollution.

Oil and gas development, a specific type of industrial process, contributes to elevated ozone concentrations. Ozone, while beneficial in the upper atmosphere, becomes harmful at ground level. Ground-level ozone is formed when sunlight interacts with certain chemicals emitted from burning fossil fuels, vehicle emissions, and industrial processes. This ozone, in combination with other airborne particles, creates smog, a visible form of air pollution that impairs visibility and poses health risks, particularly to vulnerable individuals.

The health effects of industrial pollution are significant. Long-term exposure to air pollution has been linked to various diseases, including cancers, respiratory issues, cardiovascular problems, and neurological damage. Certain chemicals, such as benzene, an industrial chemical found in gasoline, have been associated with leukemia and non-Hodgkin's Lymphoma. Additionally, fine particulate matter, such as PM2.5 and NO2, can increase the risks of colorectal and prostate cancers, impair blood vessel function, and contribute to neurological issues in children and adolescents.

Furthermore, industrial processes can also lead to water pollution. Fertilizers used in agriculture, for example, contain high amounts of nitrogen and phosphorus. When rainwater washes these fertilizers into streams and lakes, they contribute to the growth of harmful algal blooms, making the water unsafe for drinking, swimming, and fishing, which negatively impacts both human health and local food sources.

Poor sewage systems

In 2020, there were over 400,000 discharges of raw sewage into rivers in England and Wales, leading to beach closures in 2022 due to high levels of toxic waste. This issue is not unique to the UK; globally, over 80% of sewage is dumped into the seas without adequate treatment. Sewage overflows and leaks can contaminate drinking water, kill wildlife, destroy ecosystems, and impact public health, especially in vulnerable communities.

The causes of sewage pollution are multifaceted. Decades of underfunding, deregulation, inadequate monitoring, and profit prioritization have resulted in sewage systems that are unable to handle increased sewage flow. Climate change-fueled extreme weather events further exacerbate the problem, as stormwater rushes into sewer systems, causing overflows.

To address sewage pollution, governments must invest in upgrading wastewater infrastructure. This includes improving storm overflows, particularly those discharging into designated bathing waters and high-priority nature sites. Additionally, natural solutions, such as planting trees, restoring wetlands, and creating green roofs, can effectively expand the capacity of sewer systems and prevent overflows.

Public awareness and outcry about sewage pollution are crucial in prompting governments to take action. Implementing strong notification programs to alert the public about raw sewage dangers and right-to-know policies can help keep people informed and healthy, while also galvanizing support for further solutions to reduce sewage pollution.

Wildfires

The health effects of wildfire smoke exposure have been extensively studied, with evidence linking it to increased risks of cardiovascular and respiratory problems. The intensity of wildfire smoke plays a crucial role in the severity of these health impacts. Additionally, vulnerable groups such as children, senior citizens, and people with asthma or allergies, are at a higher risk of experiencing adverse health effects from wildfire pollution.

The sources of particle pollution in wildfire smoke vary, with combustion-related activities, such as wildfires, being the most common. These particles can be composed of different components, including acids (e.g., sulfuric acid), inorganic compounds (e.g., ammonium sulfate), organic chemicals, soot, metals, soil, or dust particles. The complex mixture of pollutants in wildfire smoke poses a significant threat to public health, and more research is needed to fully understand its toxic effects.

Climate change-fuelled wildfires are becoming an increasingly concerning issue, as highlighted in the 2023 State of the Air report by the American Lung Association (ALA). The report found that more than 120 million people in the United States live in areas with unhealthy levels of air pollution, with wildfires and extreme heat adding to the challenges of protecting public health. Furthermore, the report revealed that people of colour are disproportionately affected by poor air quality, being 61% more likely than white people to reside in counties with failing grades for ozone, year-round particle pollution, or short-term particle pollution.

To address the health risks associated with wildfire smoke, public health officials issue warnings about the potential respiratory problems. Additionally, studies like the Wildfire Advancing Science Partnerships for Indoor Reductions of Smoke Exposures (ASPIRE) aim to develop strategies for reducing indoor pollutant levels in public buildings during wildland fire smoke events. These efforts are crucial in mitigating the impact of wildfire pollution on human health and reducing the societal burden associated with air pollution.

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