Trucks' Air Pollution: How Many Pollutants Are We Inhaling?

Trucks are a leading source of harmful air pollution, which has a significant impact on public health. Large trucks, in particular, are the biggest culprits of near-road air pollution, with diesel trucks being the greatest contributors to harmful black carbon emissions close to major roadways. The pollutants emitted by trucks include particulate matter, nitrogen oxides, volatile organic compounds, carbon monoxide, and sulfur dioxide. These pollutants have been linked to various health issues, including respiratory and cardiac problems, lung irritation, and an increased risk of cancer. To combat truck pollution, there is a growing focus on the adoption of zero-emission trucks, the development of infrastructure for alternative fuels, and the implementation of stronger heavy-duty vehicle standards by organizations like the EPA.

Trucks are the biggest culprits of near-road air pollution

Transportation is a significant contributor to air pollution and climate change, with the sector being responsible for the largest portion (28%) of total US greenhouse gas emissions in 2022. Among the various vehicles on the road, trucks are the biggest culprits of near-road air pollution. Large diesel trucks, in particular, are the greatest contributors to harmful black carbon emissions close to major roadways, indicating that vehicle types matter more than traffic volume for near-road air pollution.

Research has found that air pollution levels right beside a major trucking route within a city are comparable to those seen beside a highway, despite the highway carrying a much higher volume of overall vehicle traffic. This suggests that the number of large trucks on the road has a more significant impact on air pollution than the total number of vehicles. The emissions from trucks contain various pollutants, including particulate matter (PM), volatile organic compounds (VOCs), nitrogen oxides (NOx), carbon monoxide (CO), and sulfur dioxide (SO2). These pollutants have been linked to a range of health issues, including respiratory and cardiac problems, lung irritation, and an increased risk of respiratory infections.

Diesel exhaust from trucks is a major contributor to PM pollution, which includes fine particles that can penetrate deep into the lungs and pose a serious threat to human health. VOCs, another pollutant emitted by trucks, react with nitrogen oxides in the presence of sunlight to form ground-level ozone, a key ingredient in smog. NOx emissions from trucks also contribute to the formation of particulate matter and ground-level ozone, causing lung irritation and weakening the body's defenses against respiratory infections.

To address the issue of truck-related air pollution, there have been calls for the adoption of zero-emission trucks powered by clean electricity or hydrogen. Federal and state programs are supporting the transition to zero-emission trucking, and investments are being made in infrastructure for electric vehicles. Additionally, the EPA has been working to reduce GHG emissions from the transportation sector, including from light and heavy-duty trucks, through various initiatives such as the SmartWay program and the Congestion Mitigation and Air Quality Management program. These efforts aim to improve air quality, protect public health, and mitigate climate change.

The number of trucks on the road matters more than the number of cars

While cars, trucks, and other vehicles are significant contributors to air pollution, recent studies suggest that the number of trucks on the road matters more than the number of cars when it comes to near-road air pollution. This indicates that vehicle type and density play a more critical role than the overall volume of vehicle traffic in determining the level of harmful emissions in the air we breathe.

A 2025 study by the University of Toronto Faculty of Applied Science & Engineering revealed that large diesel trucks are the most significant contributors to harmful black carbon emissions near major roadways. This finding holds even when compared to roads with significantly higher volumes of car traffic, such as highways. The data also showed a notable decrease in emissions on highways during weekends when personal vehicle traffic remained high, but truck traffic decreased.

The impact of trucks on air pollution is particularly concerning due to their emissions of nitrogen oxides (NOx), particulate matter (PM), and volatile organic compounds (VOCs). NOx and PM emissions from trucks contribute to smog and particulate pollution, causing respiratory issues and other health problems. Fine particulate matter, often found in vehicle exhaust, can penetrate deep into the lungs and cause serious health issues. VOCs, emitted from trucks and other vehicles, react with NOx to form ground-level ozone, a primary component of smog that irritates the respiratory system.

To address this issue, there have been calls for the adoption of zero-emission trucks and the electrification of the on-road freight system. This includes setting targets for electric truck adoption, implementing manufacturing standards, and developing incentive programs to help cities transition to cleaner transportation options. By prioritizing electric vehicle deployment in communities already struggling with poor air quality, we can improve public health and reduce the negative impacts of truck-related air pollution.

Trucks contribute to smog and particulate pollution

Trucks are a major contributor to air pollution, particularly in the form of smog and particulate pollution. A two-year study by the University of Toronto Engineering revealed that large trucks are the greatest contributors to black carbon emissions near major roadways. The study found that air pollution levels near a major trucking route within a city were almost as high as those near Highway 401, despite the road carrying less than one-tenth of the vehicle traffic. This indicates that the number of large trucks on the road has a greater impact on local air quality than the overall number of vehicles.

The emissions from trucks contribute to smog and poor air quality, which negatively affect the health and well-being of people. Smog is formed by ground-level ozone, which irritates the respiratory system, causing coughing, choking, and reduced lung capacity. Particulate matter, or PM, is another pollutant emitted by trucks that has adverse effects on human health. Exposure to PM can cause irritation and inflammation of the lungs, worsen asthma and coughing, and lower resistance to lung infections. It can even lead to premature death.

In addition to the direct health impacts, truck pollution also contributes to climate change. Transportation, including trucks, is a significant source of heat-trapping gas emissions, which contribute to global warming. The combustion of fossil fuels in truck engines releases carbon dioxide and other greenhouse gases, which trap heat in the Earth's atmosphere, leading to rising temperatures and sea levels.

To address the issue of truck pollution, there has been a push towards adopting zero-emission trucks powered by clean electricity or hydrogen. Electric trucks can eliminate tailpipe pollution entirely and significantly reduce global warming emissions compared to fossil fuel-powered vehicles. Additionally, the EPA has implemented standards and programs to reduce hazardous air pollutants from transportation sources. Through surveillance testing and the setting of vehicle and engine emissions standards, the EPA aims to further reduce emissions and improve air quality.

Zero-emissions trucks will save lives and money

The transportation sector is the second-largest source of greenhouse gas emissions in the United States, with medium- and heavy-duty trucks accounting for about a quarter of these emissions. A study by the University of Toronto Faculty of Applied Science & Engineering revealed that large trucks are the greatest contributors to black carbon emissions close to major roadways. Air pollution from trucks has been linked to various health issues, including cancer, respiratory problems, cardiac problems, and neurodegenerative issues.

To address this issue, there has been a push for the adoption of zero-emission trucks, which are powered by clean electricity or hydrogen. Zero-emission trucks offer a way to reduce tailpipe pollution, improve air quality, and reduce the negative health effects associated with traditional truck emissions. By transitioning to zero-emission vehicles (ZEVs), we can significantly reduce smog and air toxics, cut down on climate pollution, and achieve significant public health benefits.

While there are challenges to adopting ZEVs, such as higher upfront costs and undeveloped charging infrastructure, the benefits are significant. The U.S. Department of Energy (DOE) projects that by 2030, nearly half of medium- and heavy-duty trucks will be cheaper to buy, operate, and maintain as zero-emission vehicles than traditional diesel-powered combustion engine vehicles. This is due to advancements in zero-emission vehicle and fuel technologies, making clean trucks more cost-competitive and readily available.

The EPA's clean truck standards are expected to reduce one billion metric tons of climate pollution by 2055 and significantly reduce smog-forming nitrogen oxides. The transition to zero-emission trucks will not only save lives by improving air quality but also save money for fleet operators and owners. The EPA estimates that the HD industry will save approximately $3.5 billion in operating costs, including savings from reduced liquid fuel usage and lower maintenance and repair costs for ZEV technologies.

In conclusion, zero-emissions trucks are a critical component of our efforts to reduce air pollution, improve public health, and combat climate change. By investing in zero-emission technologies and infrastructure, we can create a cleaner, more prosperous, and just future while also achieving significant economic benefits and saving lives.

Electric trucks are cheaper to operate

Electric trucks are an increasingly viable option for businesses, with the potential to offer significant cost savings over diesel vehicles. While the initial cost of electric trucks can be high, particularly for larger vehicles, the total cost of ownership may be lower in the long run due to reduced maintenance, repairs, and fuel costs.

A recent study from Chalmers University of Technology in Sweden found that electric heavy goods vehicles could be cost-effective, even during periods of low diesel prices. The study, which compared battery sizes and charging prices for trucks travelling 553 kilometres, concluded that electrifying this type of vehicle was feasible from a cost perspective. This finding is significant because it indicates that electric trucks can be financially competitive with diesel trucks, even without considering the environmental and health benefits of reduced emissions.

The high cost of electric trucks is often attributed to the battery, which can be up to ten times larger than those in passenger vehicles. However, as battery technology advances, costs are decreasing, and production is becoming more efficient. This trend is expected to continue, making electric trucks more affordable for businesses. Additionally, electric trucks have fewer moving parts than diesel trucks, resulting in reduced maintenance and repair costs and a longer lifespan, further contributing to their cost-effectiveness.

The adoption of electric trucks also brings operational benefits. Real-time tracking of vehicle performance, battery levels, and charging stations enables smarter and faster decision-making, minimising downtime and improving efficiency. This increased efficiency can lead to higher customer satisfaction and loyalty, making electric fleets more attractive to businesses.

The transition to electric trucks is further accelerated by government regulations and incentives. Stricter emissions standards force businesses to choose cleaner transportation options, and financial incentives, such as subsidies and grants, encourage the adoption of electric vehicles. As a result, electric truck sales are expected to exceed diesel truck sales by 2030, demonstrating the growing recognition of their cost-effectiveness and environmental benefits.

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