Cars: Double Trouble For Air And Water Pollution

Cars are a major source of air pollution, producing about one-third of all U.S. air pollution. They emit a range of harmful pollutants, including nitrogen oxides, carbon monoxide, volatile organic compounds, sulfur dioxides, formaldehyde, and benzene. These pollutants contribute to smog, ground-level ozone, and climate change. In this article, we will explore the two main types of pollution caused by cars and the impact they have on the environment and human health.

Carbon monoxide

Cars are one of the biggest contributors to air pollution, producing about one-third of all US air pollution. One of the toxins emitted by vehicles is carbon monoxide.

The impact of carbon monoxide pollution from vehicles is exacerbated by the fact that it is emitted at street level, where humans breathe the polluted air directly into their lungs. This makes auto emissions an even more immediate health concern than toxins emitted high in the sky by industrial smokestacks.

To reduce carbon monoxide emissions from vehicles, it is important to improve fuel efficiency and promote the use of alternative propulsion methods, such as electric or hybrid engines. Additionally, reducing the number of vehicles on the road, through measures such as carpooling or public transportation, can help decrease carbon monoxide pollution and improve air quality.

Nitrogen oxides

Cars are America's biggest air quality compromisers, producing about one-third of all US air pollution. One of the pollutants that cars emit is nitrogen oxides.

NOx is a primary pollutant that can cause lung irritation and weaken the body's defences against respiratory infections such as pneumonia and influenza. It also forms ground-level ozone and particulate matter.

To reduce nitrogen oxide emissions, advancements in fuel efficiency and electric propulsion can be made. These technologies can help address the health concerns associated with auto emissions, as nitrogen oxides are toxic pollutants that directly impact the air we breathe.

Formaldehyde

Cars are America's biggest air quality compromisers, producing about one-third of all US air pollution. When vehicles burn gasoline and diesel, the exhaust from the tailpipe contains toxic pollutants including carbon monoxide, smog-causing volatile organic compounds, nitrogen oxides, sulfur dioxides, formaldehyde and benzene.

The levels of formaldehyde in car cabins can vary depending on the model and age of the car, as well as the type of fuel used. A study by Bakhtiari et al. measured formaldehyde concentrations in different car compartments before and after the refueling process, finding that compressed natural gas (CNG) and liquefied petroleum gas (LPG) resulted in lower formaldehyde emissions compared to gasoline.

To reduce exposure to formaldehyde and other pollutants in cars, it is recommended to keep car windows open to improve ventilation and reduce the concentration of pollutants. Regular cleaning and maintenance of car interiors can also help to minimise the presence of formaldehyde and other VOCs.

Benzene

Cars are a major source of air pollution and greenhouse gas emissions. One of the toxic pollutants that cars emit is benzene. Benzene is a volatile organic compound (VOC) that is released from cars, trucks and buses. VOCs react with nitrogen oxides in the presence of sunlight to form ground-level ozone, a key component of smog.

In addition to cars, petrol, oil, paint, lacquer and hobby supplies stored in garages can also increase indoor benzene levels. Attached garages can account for 40-60% of indoor benzene levels. The use of fuels such as coal, wood, gas, kerosene or liquid petroleum gas (LPG) for space heating and cooking can also lead to higher concentrations of benzene indoors.

National benzene emissions data in Canada and the US show that mobile sources, including cars, are significant contributors to ambient benzene levels. In the US, it is estimated that 47% of benzene emissions come from mobile sources, with 60% of that coming from on-road vehicles.

Overall, benzene is a harmful pollutant that is released into the air by cars and other sources, posing risks to human health and the environment.

Greenhouse gases

Cars are a major source of air pollution, producing about a third of all air pollution in the US. One of the two main types of pollution caused by cars is the emission of greenhouse gases, predominantly carbon dioxide. These gases contribute to global climate change.

In addition to carbon dioxide and carbon monoxide, the burning of gasoline and diesel releases other toxic pollutants. These include smog-causing volatile organic compounds, nitrogen oxides, sulfur dioxides, formaldehyde, and benzene. Nitrogen oxides, in particular, are of concern as they can form ground-level ozone and particulate matter, which can irritate the lungs and weaken the body's defences against respiratory infections.

The transportation sector is a major contributor to nitrogen oxide pollution, with California's transportation sector accounting for nearly 80% of nitrogen oxide emissions in the state. The high temperatures produced by internal combustion engines burn nitrogen in the air, forming nitrogen oxide (NO) and nitrogen dioxide (NO2), collectively known as NOx.

Overall, the emission of greenhouse gases and other pollutants from cars has a significant impact on both the environment and human health, highlighting the importance of reducing vehicle emissions and transitioning to cleaner energy sources.

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