In hot temps, it’s time to ask about pollutants
As the temperature heats up, the Clean Air Council reminds us of the link between hot temps and consequences for Philadelphians
DYK today is a Code Orange Air Quality Action Day in Philadelphia? Tomorrow (Friday) is likely to hit 95°F, the highest temperatures we’ve seen in Philadelphia this year and it’s well documented that neighborhoods with fewer trees and other green space could be over 20° hotter. Individuals who have to work outside or in unairconditioned environments have an increased risk of heat stress, as do the elderly, people who are overweight, have high blood pressure, or suffer from heart disease. Not only are those taking blood pressure medication more susceptible to heat stress, also those taking ADHD-related stimulants, antidepressants, and antipsychotics. Even those taking allergy medications like decongestants and antihistamines are at an increased risk of heat stress. Besides the obvious best practices of drinking water and trying to stay cool, it’s most important to check on your friends, family and neighbors on hot days, particularly anyone predisposed to heat stress.
But extreme heat doesn’t stop there. Heat literally creates asthma-inducing air pollution by baking nitrogen oxides (NOx) and volatile organic compounds (VOC) into ground-level ozone, commonly known as smog. And smog is getting worse in Philadelphia even though the U.S. Environmental Protection Agency (EPA) hasn’t updated ozone standards since 2015 (it’s supposed to every 5 years). With an updated ozone standard we would have fewer air quality days classified as “good”, but even without one, Philly only had 213 good air quality days in 2021, the lowest since 2017. In the effort to reduce gas prices the Biden Administration has already lifted summer restrictions on more polluting blends of gasoline, which could increase smog pollution this summer.
While Philadelphia is filled with transportation and industrial pollution sources, smog is a regional problem. The entire state of Pennsylvania and all Eastern states from Maine to Northern Virginia are collectively designated as the “ozone transport region” by the EPA, which causes stricter regulations for the many substances classified as VOCs. VOCs readily lose an oxygen atom in extreme heat, which then bonds to the oxygen molecule (02), creating ground-level-ozone (03). The substance that supports all human life on this planet turns into dangerous air pollution in an instant under extreme heat!
So how do we reduce ozone levels? We have to look at both the pollutants that form smog and the pollutants that cause extreme heat. NOx and the greenhouse gas carbon dioxide are produced by almost every form of combustion and VOCs evaporate from almost all chemicals, from household to industrial. Whenever you are smelling nail polish, paint, gasoline or glue, those are evaporating VOCs.
Our noses don’t deceive us, and the most well-known VOC smell is also a massive driver of climate change and smog pollution: natural gas. Philadelphia Gas Works is the largest public gas utility in the country and city residents know to be aware of the smell of gas. Natural gas is both a product and a pollutant, and it’s both a greenhouse gas with 87 times the global warming power of carbon dioxide over a 20-year time period and a VOC. When natural gas is extracted, largely by hydraulic fracturing, it is initially about 80% methane and 20% other VOCs and after processing, retail natural gas is about 92% methane. By using less gas, even converting to electric appliances, and advising the City of Philadelphia to do the same, Philadelphians can both reduce the amount of natural gas in the city while reducing the need to drill for it. Only Texas drills for more gas than the state of Pennsylvania.
Just as residents can convert their gas appliances to electric to reduce air pollution, the gas industry can do the same! Later this year the EPA will publish its final rule to set methane and VOC pollution standards for existing gas well sites and compressor stations that will have a major impact on smog pollution in the Ozone Transport Region. EPA has already published plans to require pressure regulators at well sites, known as pneumatic devices, that do not vent gas to the atmosphere when pressure becomes too great. EPA could go even further and ban glycol dehydrators which use chemicals and combustion to increase the methane content of the gas stream during processing. Just like the desiccant packets in our clothes and dried food like jerkies, industrial desiccant dehydrators have been used for over 70 years by the oil industry to remove impurities in the product stream. The gas industry can do the same, significantly reducing air pollution.
As temperatures increase and smog levels become harmful for vulnerable populations it is a great time to check on those close to you and communicate with your elected officials about the need for pollution reductions that will reduce extreme heat and air pollution. You can directly email EPA Administrator Michael Regan here.
If you want more information about air pollution in Philadelphia, please check out this recent event hosted by Climate Action PA where myself and Temple Professor of Geography and Urban Studies Christina Rosan discussed the variety of air pollution sources in Philly.