Philly’s air quality hovered in the ‘unhealthy’ range often in the 1980s

The air pollution this week as smoke particles from record-setting Canadian wildfires saturated Philadelphia was the worst since 2008. But 35 years ago, this would have been just another day.

According to Philadelphia Department of Public Health records, in 1980 nearly every other day saw the air quality index hover into the same “unhealthy” range seen Tuesday and Wednesday.

The index is a measure of five common pollutants and runs on a scale from 0 to 500, with a rating over 150 considered “unhealthy.” From 1980 to 1985, Philadelphia saw 100 to more than 150 days annually with air quality in that red zone.

In 2020, just five days hit that threshold. And, since 2016, the city has recorded more days in the “good” range than not.

That improvement — and the introduction of a uniform index to measure air quality — can be largely attributed to the introduction of environmental controls in the late 1960s and ‘70s, like the Clean Air Act. And since then, the EPA has continually ratcheted down the allowable levels of particulate matter.

Coal-burning industries were not uncommon in Philadelphia — a major manufacturing hub since the Victorian era — well into the modern age and pollution was often accepted as a fact of life.

City Hall’s exterior had been darkened by coal ash particulates before the structure was even fully complete in 1901. Into the 1960s, more than half of all days would have been regarded as unhealthy by modern air quality standards.

But the introduction of controls were contentious in a manufacturing city like Philadelphia. After the measures were introduced, New Jersey threatened to sue Pennsylvania and the Environmental Protection Agency over the failure to enforce the rules in Philadelphia when factory pollution continued wafting over the Delaware River and into the Garden State.

A 1983 Inquirer report documented a stretch of summer weather that saw air quality levels fall below federal standards every day for about two weeks straight. However, the same report notes that air quality levels in Philadelphia had improved dramatically compared to a decade prior, crediting the introduction of environmental standards.

The continued improvement is also attributable to other factors, like the decline of polluting industries as the city deindustrialized.

The local air quality index notably jumped between 2019 and 2020, following the explosion and subsequent closure of a major oil refining complex in South Philly. The plant had been the single-largest stationary source of air pollution in the city.

Still, even as local sources of pollutants have lessened, global carbon levels have continued to creep upward, and environmental experts say climate change is at fault for the wildfires that have scorched across Canada.

”It is a simple fact that Canada is experiencing the impacts of climate change, including more frequent and more extreme wildfires,” Canadian Natural Resources Minister Jonathan Wilkinson told reporters during a news conference last week.