Columbus, Ohio's Air: Why So Polluted?

Columbus, Ohio, has been labelled the most polluted city in the United States by a Swiss air technology company, IQAir, in a report released in March 2023. The report, which is based on air quality alone, contradicts claims by the Ohio Environmental Protection Agency (EPA), which states that air quality in Columbus has been improving for several years. This discrepancy has sparked debates about the accuracy of air pollution data and the need for additional air quality monitoring in the city. While Columbus has made strides in improving air quality, the high levels of pollution have significant health implications for residents, particularly those with asthma and cardiovascular disease.

The impact of air pollution on health

Columbus, Ohio, has been described as the most polluted major city in the US by IQAir, a company that specialises in monitoring air quality. This assertion has been disputed by the Ohio EPA, which claims that the air quality in Columbus meets federal standards. However, the air quality in Columbus has been shown to have adverse health effects on its residents.

Air pollution is defined as the presence of contaminants in the atmosphere, such as dust, fumes, gases, and odours, in quantities that can be harmful to human health. The primary pathway of exposure is through the respiratory tract, where pollutants cause inflammation, oxidative stress, immunosuppression, and mutagenicity in cells throughout the body. These pollutants can also enter the bloodstream and circulate throughout the body, leading to systemic inflammation and carcinogenicity.

The pollutants with the strongest evidence for adverse health effects include particulate matter (PM), carbon monoxide (CO), ozone (O3), nitrogen dioxide (NO2), and sulphur dioxide (SO2). Fine particulate matter, such as PM2.5, is of particular concern as it can penetrate deep into the lungs and cause damage to tissues and cells. Short-term exposure to high levels of PM2.5 can lead to reduced lung function, respiratory infections, and aggravated asthma. Long-term exposure increases the risk of chronic diseases such as stroke, heart disease, chronic obstructive pulmonary disease, and cancer.

Ozone, a powerful lung irritant, is another significant pollutant in Columbus. Inhalation of ozone can cause inflammation and damage to the delicate lining of the small airways, impacting multiple body systems. High ozone levels can lead to breathing problems, chest tightness, coughing, and shortness of breath within hours of exposure, even in healthy young adults.

The health effects of air pollution are not limited to physical ailments. Psychosocial stressors, such as poverty and racial/ethnic discrimination, can amplify the harmful effects of air pollution. Additionally, certain populations are more susceptible to the adverse health impacts of air pollution, including children, the elderly, pregnant women, and individuals with pre-existing chronic conditions.

Columbus is taking steps to improve its air quality and reduce car emissions, including the introduction of an electric bus fleet and a rebate program for e-bike purchases. These initiatives aim to reduce the health risks associated with air pollution and create a healthier environment for the city's residents.

The accuracy of air pollution data

Columbus, Ohio's air quality is generally considered clean, with the city achieving "'good'" ratings each year since 2012. However, there are concerns about the accuracy of the data used to make these assessments.

The US Environmental Protection Agency (EPA) and local agencies like the Ohio EPA monitor air pollution levels. They track pollutants such as PM2.5, PM10, ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide. The EPA uses the Air Quality Index (AQI) to consolidate these pollutants into a single number for easy comparison of health risks. Smog alerts in Columbus are issued by the Mid-Ohio Regional Planning Commission (MORPC) when any pollutant reaches a concerning level.

While Columbus's air quality is generally rated as good, there are concerns about the accuracy and comprehensiveness of the data. The placement and number of sensors can impact the results, and the combination of data from different types of sensors can be challenging and potentially misleading.

To address these concerns, Columbus is implementing projects to improve air quality and reduce car emissions, including the introduction of an electric bus fleet and a rebate program for e-bike purchases. These initiatives aim to reduce air pollution and provide a healthier environment for residents. Additionally, individuals can take proactive steps by monitoring air quality data and limiting outdoor activities during periods of elevated pollution levels, especially for those with respiratory issues.

The sources of air pollution

Columbus, Ohio, has been labelled the most polluted city in the United States by a Swiss air quality technology company, IQAir. However, the Ohio Environmental Protection Agency (EPA) and IQAir's conclusions disagree. IQAir's report states that Columbus's average concentration of fine particle pollution (PM2.5) was 13.1 micrograms per cubic meter (µg/m3) in 2022. The World Health Organization's guideline for long-term PM2.5 exposure is less than 5 µg/m3. The EPA has a higher threshold of 12.

PM2.5 is a result of factors like combustion engines, construction, and burning wood and coal. Columbus's worst air pollution rating comes from ozone pollution, which coincides with summer, running from March through October. Hot, sunny conditions are required for ozone formation, which is created when precursor pollutants, nitrogen oxides (NO2) and volatile organic compounds (VOCs), cook in sunlight. Primary ozone sources include vehicle emissions from cars, trucks, and buses, as well as power plants and other sources of combustion. Columbus is considered to have the most polluted air due to its population and the amount of transportation that takes place within the state.

The Ohio EPA and the Mid-Ohio Regional Planning Commission (MORPC) are pushing back on IQAir's conclusions about Columbus's air quality. They argue that regulatory monitors in Columbus haven't been painting an accurate picture of the amount of PM2.5 in the air because there aren't enough in operation. The Ohio EPA tracks air quality across the state using more than 250 high-quality air monitors, which MORPC uses to create their air quality forecast. MORPC's 2022 report indicates that ozone quality has significantly improved in recent years, and only 4% of days in their November 2021-October 2022 monitoring period logged PM2.5 levels exceeding the EPA threshold.

Columbus is embracing a variety of projects that could improve air quality and reduce car emissions, including the rollout of an electric bus fleet and an impending rebate program for e-bike purchases. MORPC is also in the process of concluding a year-long study gathering data from air sensors in the community to look at pollution patterns. They plan to use this information for additional strategies to reduce pollution in certain zip codes, primarily in Black and lower-income communities, where life expectancy has dropped.

Projects to improve air quality

Columbus, Ohio's air pollution is largely attributable to two pollutants: fine particulate matter (PM2.5) and ozone. The US Environmental Protection Agency (EPA) and local agencies monitor air pollution levels, and smog alerts are issued by the Mid-Ohio Regional Planning Commission (MORPC) when any pollutant registers an AQI reading over 100.

While Columbus has made significant strides in improving air quality over the years, there are still concerns about the accuracy of the data due to the limited number of regulatory monitors in the city. To address this, various projects have been undertaken to improve air quality and reduce car emissions:

Electric Bus Fleet Rollout:

The Central Ohio Transit Authority (COTA) has embraced the idea of an electric bus fleet, which will help reduce emissions from vehicles, a primary source of ozone pollution.

Rebate Program for E-bike Purchases:

Encouraging the use of e-bikes through rebate programs can reduce the number of cars on the road, thereby lowering emissions and improving air quality.

Air Quality Monitoring Network:

MORPC and Franklin County Public Health (FCPH) have partnered to establish an air quality monitoring network to gather more localized data. This project will help guide strategies to make the region's air healthier. The network will include strategic deployment of air quality sensors in Columbus and throughout Franklin County, with the aim of empowering communities by providing real-time access to air quality data.

Community Engagement and Communication:

The project also entails engaging with community members through local forums to gather input and devise a communication strategy. This ensures that communities can directly benefit from the data, such as receiving grants to address inequities in air quality.

Amtrak Expansion:

Possible Amtrak expansion could have a statewide impact on reducing car emissions and improving air quality.

CoGo Bikeshare:

MORPC also promotes the use of the CoGo Bikeshare program, which offers an easy and quick way to get around downtown Columbus. For a small fee, individuals can access hundreds of bikes, reducing the need for car travel.

These projects demonstrate a comprehensive approach to improving air quality in Columbus, Ohio, by addressing data accuracy, reducing emissions, and engaging the community in finding solutions.

The disparity in air quality across different communities

Columbus, Ohio, has been labelled the most polluted city in the United States in terms of air quality. However, this claim has been disputed by the Ohio Environmental Protection Agency (EPA) and the Mid-Ohio Regional Planning Commission (MORPC). The IQAir report that made this claim has been criticised for its methodology, particularly the placement and combination of data from different types of sensors.

Despite the debate over Columbus' ranking, it is evident that air pollution is a significant issue in the city, and it has been acknowledged that more air quality monitoring is needed. Disparities in air quality across different communities in Columbus have been noted, with disadvantaged and underserved communities experiencing significantly higher levels of pollution. This is particularly concerning given Ohio's high paediatric asthma rate, as poor air quality increases the frequency and severity of asthma attacks.

The MORPC is actively working to address this issue by gathering data from air sensors in the community to identify pollution patterns. They plan to use this information to develop strategies to reduce pollution in specific zip codes, particularly in Black and lower-income communities, where life expectancy has decreased. This initiative aims to improve environmental justice and enhance the quality of life for all residents.

Additionally, Columbus is embracing projects to improve air quality and reduce car emissions, such as the introduction of an electric bus fleet and a rebate program for e-bike purchases. These efforts demonstrate a commitment to addressing air pollution and its impact on vulnerable populations.

While the extent of Columbus' air pollution may be debated, it is clear that the city and its partners are taking active steps to improve air quality and reduce health risks for all residents, especially those in disadvantaged communities. These efforts are crucial in mitigating the adverse effects of air pollution on public health and well-being.

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