Philadelphia's Air Quality: A Breath Of Fresh Air?

Philadelphia, the largest city in Pennsylvania, has been working to address its air pollution problem. The city recently updated its regulations on toxic air pollution from industrial facilities, which has been praised as a positive step towards reducing carcinogenic materials in the region's air. Despite this, some critics argue that the revisions do not go far enough, as mobile sources of air pollution, such as vehicles and airplanes, are not subject to the new regulations. The city's air quality is primarily affected by ozone, a gas pollutant formed from precursor pollutants reacting to sunlight, and fine particulate matter. Philadelphia's air quality varies significantly from neighbourhood to neighbourhood, with some areas experiencing \good\ air quality, while others fall into the \moderate\ or \unhealthy\ categories.

Philadelphia's air quality is primarily affected by ozone

Ozone is harmful to the health of Philadelphia residents, especially children, older adults, and those with asthma and other lung diseases. It can cause throat and lung irritation, chest pain, and coughing. In some cases, it can be likened to experiencing sunburn inside the airways. While healthy bodies may eventually repair such damage, those with compromised systems may take much longer to recover, if at all.

The American Lung Association's annual air quality "report card" found that in 2016-2018, nearly half of all Americans were exposed to unhealthy air. The Philadelphia-Reading-Camden area ranked 23rd for worst ozone pollution nationally out of 229 metropolitan areas. The report also revealed that Philadelphia experienced an average of 10.8 weighted days of unhealthy ozone levels, far above the legal limit.

Ozone levels in Philadelphia have been attributed to various factors, including emissions from vehicles and industrial sources. The city's high ownership of motor vehicles contributes to mobile emission sources being the largest contributor to the city's poor air quality. However, Philadelphia has taken steps towards cleaner energy and transportation, and the Philadelphia Energy Solutions refining complex, the city's largest stationary emission source, has been shut down. The city is also working to increase the number of electric and hybrid vehicles on the road and make public transportation and green transportation more accessible.

The city has recently changed how it regulates toxic air pollution

Philadelphia, the largest city in Pennsylvania, has consistently averaged an annual Air Quality Index (AQI) level in the "good" category in recent years. However, this obscures the city's pollution events, which can lead to "action days" where the AQI is rated as "moderate" or "unhealthy".

Ozone (O3) is a particular concern in Philadelphia, with the city failing to meet federal attainment levels in 2019. The production of ozone is exacerbated by extreme heat, which has been more prevalent in recent years. Other sources of air pollution in Philadelphia include vehicle emissions, upwind sources from other states, and industrial sources.

In April 2023, Philadelphia's Air Pollution Control Board approved an update to the city's Air Management Regulation 6 (AMR VI), titled "Control of Emissions of Toxic Air Contaminants". This update focuses on controlling a category of air pollutants known as Toxic Air Contaminants (TACs) or Hazardous Air Pollutants (HAPs), which include compounds like asbestos, lead, arsenic, and benzene. The revision more than doubles the number of regulated compounds and lowers the emissions thresholds that trigger health risk assessments.

The updated AMR-VI is a response to concerns raised by community members about the concentration of toxic emissions in Black and Brown neighbourhoods. It aims to protect Philadelphians from exposure to toxic air pollution and improve the health of vulnerable residents. The new regulation will require large pollution emitters to consider the background cancer risk around their facilities when seeking regulatory approval.

While some applaud the updated AMR-VI as a significant step forward, others argue that it may not go far enough. Mobile sources of air pollution, such as airplanes, ships, and trucks, are not subject to the regulation. Additionally, the Health Department is unsure how many existing facilities will ultimately be required to assess the health risks of their pollution.

Air pollution varies across neighbourhoods

Philadelphia, the largest city in Pennsylvania, has been acknowledged to have "'good'" air quality in recent years, according to the Air Quality Index (AQI). However, this obscures the city's pollution events, which give rise to unhealthy pollution days, or "action days".

Philadelphia's air quality is primarily affected by ozone, a gas pollutant formed from precursor pollutants reacting in sunlight. The city ranks among the 25 worst metropolitan areas for ozone and year-round particle pollution. The American Lung Association attributes this to secondary pollutants, which are not directly emitted from sources like tailpipes, but rather formed in the atmosphere and have multiple formation pathways.

The city's individual neighbourhoods can vary significantly in terms of air quality. Peleg Kremer, PhD, assistant professor of Geography and the Environment, notes that "pollution varies at a very fine scale". The research team at Villanova University is measuring hyper-localised air quality data against factors such as surrounding vegetation, building height, building materials, and demographics. Their findings could provide valuable insights for urban planners to reduce air pollution in the future.

The Department of Public Health in Philadelphia provides real-time updates and resources about air quality in the city. The city has also recently updated its regulations on toxic air pollution from industrial facilities, addressing compounds like asbestos, lead, arsenic, and cancer-causing benzene. These changes are expected to positively impact the region's air quality and public health.

The city's Air Pollution Control Board approved a revision to a regulation that covers compounds like asbestos, lead, arsenic and benzene

Philadelphia, the largest city in Pennsylvania, has been acknowledged to have "'good'" air quality in recent years, according to the Air Quality Index (AQI). However, the city has also experienced days of unhealthy pollution levels, referred to as "action days". Philadelphia's air quality is primarily affected by ozone, a gas pollutant formed from precursor pollutants reacting to sunlight. The American Lung Association ranks Philadelphia as one of the worst metro areas for ozone and year-round particle pollution.

In May 2023, the city's Air Pollution Control Board approved a revision to a regulation that covers toxic compounds such as asbestos, lead, arsenic, and benzene. This revision is a significant step forward in reducing carcinogenic materials in the air around Philadelphia. The original regulation, dating back to 1981, covered approximately 100 toxic air pollutants. The recent revision more than doubles the number of regulated compounds to 217.

The new policy allows the Health Department to consider the background levels of pollutants when evaluating permit applications. If a facility's emissions of toxic air pollutants would create an excess cancer risk of more than 50 in a million, the city will reject the permit application. The city will also reject permits if a facility's emissions push the existing cancer risk from that pollutant above 100 in a million. For lower-risk levels, the facility may be required to implement mitigation measures, such as installing pollution control technology or adjusting operating hours.

The revision also lowers the emissions thresholds that trigger health risk assessments. This change reflects the understanding that even lower concentrations of certain chemicals can pose health risks. The new process will consider the cancer risk associated with specific pollutants, such as benzene, when evaluating permit applications. However, it does not take into account the cumulative impacts of multiple pollution sources or other factors such as pre-existing community health and demographic characteristics.

The Air Management Services division of the Health Department initiated research for this update in 2018, and the revision will come into effect at the beginning of 2024. This amendment is a positive step towards improving air quality and protecting the health of Philadelphia's residents.

The general public is less likely to be affected by air pollution than members of sensitive groups

Philadelphia, the largest city in Pennsylvania, has been acknowledged to have an air pollution problem. The city ranks as one of the worst metro areas for ozone and year-round particle pollution, with ozone being the primary pollutant affecting the city's air quality. Despite this, Philadelphia has, in recent years, consistently averaged an annual Air Quality Index (AQI) level in the "good" category. However, this obscures the fact that there are still days when pollution levels are high enough to be considered "unhealthy".

The Air Quality Index (AQI) provides a way to monitor air pollution levels and protect public health. When the AQI value for particle pollution is between 101 and 150, or Code Orange, air quality is considered "unhealthy for sensitive groups". During these periods, members of sensitive groups are advised to reduce prolonged or heavy exertion to minimise their exposure to air pollution.

The Department of Public Health in Philadelphia provides real-time daily updates and resources about the city's air quality. The city's air monitoring stations measure criteria pollutants such as carbon monoxide, nitrogen dioxide, particulate matter, and sulphur dioxide. This information is crucial for the public, especially sensitive groups, to make informed decisions about their outdoor activities and protect their health.

While Philadelphia's annual average AQI level is "good", the city still experiences days with elevated pollution levels that can pose risks to sensitive groups. The general public is generally less likely to experience health effects from air pollution, but members of sensitive groups are more vulnerable and may suffer more serious consequences.

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