Car Pollution: Rise Or Fall?

Cars, trucks, and buses powered by fossil fuels are major contributors to air pollution. Vehicle emissions come in two main types: carbon dioxide pollution and air pollution. While carbon dioxide is not directly harmful and is vital for life on Earth, burning gasoline and other fossil fuels releases far more carbon dioxide than the planet can handle. This overload of carbon dioxide in the atmosphere leads to warming land and ocean temperatures, causing more severe storms, droughts, and other weather events. In addition to carbon dioxide, vehicle emissions include toxic pollutants such as carbon monoxide, nitrogen oxides, volatile organic compounds, and particulate matter, which have adverse effects on human health and the environment. While electric vehicles and newer, more efficient cars emit less pollution, the rising popularity of SUVs and the export of used heavy-duty vehicles to developing countries contribute to the ongoing problem of car pollution.

Electric vehicles reduce pollution

Cars, trucks, and buses powered by fossil fuels are major contributors to air pollution. Transportation emits more than half of nitrogen oxides in the air, and vehicles cause nearly 75% of carbon monoxide pollution in the United States. Vehicle emissions also include harmful Volatile Organic Compounds (VOCs), which react with nitrogen oxides in the presence of sunlight to form ground-level ozone, a primary ingredient in smog.

Electric vehicles (EVs) have no tailpipe emissions, which means they do not emit these harmful pollutants. However, generating the electricity used to charge EVs may create carbon pollution, depending on the energy source. For example, using coal or natural gas emits carbon pollution, while renewable resources like wind or solar do not. Research shows that even when accounting for electricity emissions, EVs are responsible for lower levels of greenhouse gases (GHGs) than average new gasoline cars.

According to a report by the Electric Power Research Institute (EPRI) and the NRDC, using electricity instead of petroleum to power transportation can significantly reduce emissions of GHGs and other air pollutants. This is supported by additional studies, which estimate that electrifying light-duty personal vehicles could reduce carbon pollution by 430-550 million metric tons annually by 2050.

Furthermore, EVs reduce emissions of nitrogen oxides (NOx) and PM2.5, which are particularly harmful to human health. EVs achieve this reduction through regenerative braking, which reduces brake wear and captures particulates, preventing their release into the environment.

Overall, while electric cars do not completely eliminate pollution, they significantly reduce levels of air pollution compared to petrol and diesel cars.

Vehicle emissions and health

Cars, trucks, and buses powered by fossil fuels are major contributors to air pollution. Transportation emits more than half of nitrogen oxides in the air and is a major source of heat-trapping emissions in the US. Vehicle emissions contribute to the formation of ground-level ozone (smog), which can trigger health problems such as aggravated asthma, reduced lung capacity, and increased susceptibility to respiratory illnesses, including pneumonia and bronchitis.

Motor vehicles, particularly those used for freight, are also a major source of fine particulate matter. Many scientific studies have linked breathing particulate matter to significant health problems, including asthma, chronic bronchitis, and heart attacks. Diesel particulate matter is of particular concern because long-term exposure is likely to cause lung cancer. Levels of traffic-related air pollution are higher near major roadways that have high traffic volume. People in low-income communities and communities of color are disproportionately exposed to higher levels of air pollution. Marginalized by urban segregation in US cities, these communities are often located near freight centers and heavily traveled roadways and can lack access to the resources to adapt to or move away from air pollution and climate-related damage. Analysis of emissions from cars, SUVs, trucks, and buses shows that exposure to harmful particulate matter air pollution is inequitable: Asian Americans are, on average, exposed to 34% higher PM2.5 concentrations than the average person in the US, and Black people experience concentrations 24% higher than average.

Vehicle emissions come in two main forms: carbon dioxide pollution and air pollution. Carbon dioxide, or CO2, is not harmful in itself—it is vital for life on Earth. However, burning gasoline and other fossil fuels release far more carbon dioxide than the planet can handle. The higher the level of carbon dioxide, the higher the global mean temperature. Oceans have been absorbing about 90% of the extra heat caused by carbon dioxide pollution, but they may have hit their limit, as there has been an unprecedented rise in ocean temperatures. This is causing warming land and ocean temperatures, resulting in more severe storms, droughts, and other weather events. Every gallon of gasoline burned releases 20 pounds of carbon dioxide into our atmosphere, where it stays for thousands of years.

In addition to carbon dioxide, vehicle emissions contain toxic pollutants, including carbon monoxide, smog-causing volatile organic compounds, nitrogen oxides, sulfur dioxide, formaldehyde, and benzene. Exposure to pollution is inequitable, and the harms fall disproportionately on Latinos, Blacks, and lower-income households.

Air pollution and social inequality

Air pollution is a pressing global issue, causing around 7 million deaths worldwide annually. It is a major contributor to climate change, which leads to more frequent and intense heat waves, rising sea levels, flooding, droughts, and wildfires that devastate communities. While air pollution affects everyone, it disproportionately impacts certain communities, exacerbating social inequality.

One factor contributing to social inequality in air pollution exposure is income disparity. Studies have consistently shown that low-income communities are exposed to higher levels of air pollution. This is partly due to urban segregation, where marginalized communities of color are often located near freight centers and heavily traveled roadways. Additionally, lower-income households tend to live in areas with higher traffic and industrial activity, increasing their exposure to pollutants. Income also influences an individual's ability to mitigate the effects of air pollution. Those with lower incomes have reduced access to resources, infrastructure, and prevention services, making them more vulnerable to the health risks associated with air pollution.

Racial and ethnic disparities also play a significant role in the unequal impact of air pollution. People of color, especially Blacks, Hispanics, and Asians, face higher exposure to harmful particulate matter and air pollutants. This is a result of historical and ongoing residential segregation, with communities of color being situated closer to pollution sources. For example, Asian Americans are exposed to 34% higher PM2.5 concentrations than the average person in the US, while Blacks experience 24% higher concentrations. Additionally, racial and ethnic minorities may experience greater health responses to pollution due to factors such as chronic stress from discrimination.

Socioeconomic status, including employment status, education level, and income, further influences the impact of air pollution. Those with lower socioeconomic status are more susceptible to the effects of air pollution due to pre-existing health conditions, poor housing, inadequate diets, and stress. This creates a vicious cycle that perpetuates the disparity in health outcomes between different socioeconomic groups.

While air pollution is a global issue, it disproportionately affects developing countries and low- and middle-income regions. According to the World Health Organization (WHO), 98% of cities in developing countries with over 100,000 inhabitants failed to meet air quality guidelines in 2016, compared to 56% in developed countries. Additionally, approximately 90% of air pollution-related deaths occur in low- and middle-income countries, highlighting the unequal burden of this environmental issue.

Addressing the issue of air pollution and its contribution to climate change is crucial for improving air quality and reducing health risks, especially for vulnerable and underserved communities. The transition to zero-emission vehicles, such as electric cars, trucks, and buses, can significantly reduce pollution from passenger vehicles and contribute to the development of clean, renewable energy sources. Additionally, conscious government action and city planning that prioritizes vulnerable groups are essential to mitigating the impact of air pollution on socially disadvantaged communities.

Gasoline fumes and air pollution

Cars, trucks, and buses powered by fossil fuels are major contributors to air pollution. When vehicles burn gasoline, fumes escape into the air, and the exhaust from the tailpipe contains toxic pollutants, including carbon monoxide, nitrogen oxides, particulate matter, volatile organic compounds, sulfur dioxide, formaldehyde, and benzene. These pollutants have adverse effects on human health, with studies linking them to various types of cancer, asthma, heart disease, birth defects, and eye irritation. They also contribute to environmental issues such as global warming, rising sea levels, and increased natural disasters.

Gasoline is a toxic and highly flammable liquid. The vapors released when it evaporates, as well as the substances produced when it burns, contribute to air pollution. Burning gasoline produces carbon dioxide, a greenhouse gas that stays in the Earth's atmosphere for thousands of years, leading to warming land and ocean temperatures and more severe weather events. Every gallon of gasoline burned releases about 19 to 20 pounds of carbon dioxide, and in 2022, combustion of gasoline accounted for about 22% of total US energy-related CO2 emissions.

To address the issue of gasoline fumes and air pollution, several measures have been implemented. The Clean Air Act, first passed in 1970, aims to reduce air pollution by requiring engines and fuels to produce fewer emissions. This includes mandating emissions-control devices, cleaner-burning engines, and ultra-low sulfur gasoline. California, a state with high transportation sector emissions, is among those phasing out gasoline. The development of electric vehicles, including cars, trucks, and buses, is also helping to reduce pollution from passenger vehicles and increase the use of clean, renewable energy sources.

While these efforts are making progress, there is still a long way to go to ensure equitable access to clean air. Marginalized communities, particularly those of color and lower-income households, are disproportionately affected by vehicle pollution due to their proximity to heavily traveled roadways and freight centers. Additionally, the rise in SUVs has contributed significantly to the increase in energy-related CO2 emissions, and the oil and gas industry remains the largest source of methane pollution in the US. Addressing these issues and transitioning to cleaner alternatives are crucial steps toward mitigating the impact of gasoline fumes on air pollution.

The rise of SUVs and emissions

The rise in car pollution is largely attributed to the increasing number of SUVs on the road. In 2023, there were over 360 million SUVs globally, with sales increasing by around 3% between 2021 and 2022. SUVs are heavier and less fuel-efficient than average cars, emitting approximately 20% more carbon dioxide (CO2). This has resulted in a significant increase in combustion-related CO2 emissions, with SUVs accounting for over 20% of the growth in global energy-related CO2 emissions in 2023. If the global fleet of SUVs was considered a country, it would be the fifth-largest emitter of CO2, surpassing the emissions of Japan and other major economies.

The shift towards larger and heavier cars, including SUVs, has been identified as a key trend in the automobile industry. In 2022, SUVs accounted for around 46% of global car sales, with notable growth in the United States, India, and Europe. This trend has been driven by various factors, including the appeal of SUVs as status symbols, enhanced comfort, and marketing strategies. However, the increase in SUV sales and their associated emissions have had a detrimental impact on the environment and public health.

SUVs require larger batteries, which can strain battery supply chains and increase the demand for critical minerals needed for battery production. Additionally, the production of materials used in SUV manufacturing contributes to higher indirect emissions. The rise in SUV sales has offset the efficiency improvements in smaller cars and carbon savings from electric vehicles. As a result, the growing demand for SUVs was the second-largest contributor to the increase in global CO2 emissions from 2010 to 2018, with their annual emissions surpassing the total emissions of some countries.

While the number of electric SUVs is increasing, they still account for a small percentage of the total SUV market. In 2023, only 5% of SUVs on the road were electric, although they represented over half of global electric car sales in the same year. The transition to electric SUVs is crucial in reducing pollution from passenger vehicles and achieving net-zero emissions by the middle of the century. However, the larger batteries required for electric SUVs present challenges in terms of resource management and supply chain sustainability.

Overall, the rise in SUVs has significantly contributed to the increase in car pollution, particularly in terms of CO2 emissions. The trend towards larger and less fuel-efficient vehicles has had detrimental environmental and health impacts, highlighting the need for a transition to cleaner alternatives and more sustainable transportation solutions. Addressing the emissions from SUVs is essential in mitigating climate change and improving air quality worldwide.

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