Leaked memos make it clear that Big Oil has known about the links between air pollution and fossil fuel combustion for at least 50 years—and, in a familiar pattern, has for decades been doing everything it can to bury the threat to its bottom line. 

Internal memos and reports from fossil heavy hitters like Esso dating from the mid-1960s reveal that the industry “was long aware that it created large amounts of air pollution, that pollutants could lodge deep in the lungs and be ‘real villains in health effects’, and even that its own workers may be experiencing birth defects among their children,” writes The Guardian.

An internal technical report produced by Shell in 1968 shows just how much that company knew about the link between air pollution and the internal combustion engine, citing both sulphur and nitrogen dioxide as particularly worrisome and explicitly confirming its understanding that small particulates are “the real villains in health effects.”

The language of the report reveals the fossil to be far from repentant about its role in destroying air quality, however, speaking of the need to “reluctantly” accept that cars “are by far the greatest source of air pollution,” and testily anticipating an upcoming “clamour” to reduce NO2 emissions, “probably based on suspected long-term chronic effects.”

By 1980, Imperial Oil’s private concerns were such that it was making plans to study the incidence of cancer among industry workers, as well as birth defects in their children. Meanwhile, Esso experts, having discovered in 1971 that the air in New York City was, as The Guardian puts it, “rife with tiny fragments of aluminum, magnesium, and other metals,” flagged the possibility of changing vehicle designs to reduce harmful emissions.

The next 10 years brought a decided shift in the tenor and trajectory of Big Oil’s response to its air pollution, as independent scientists began to amass their own damning body of evidence about the dangers of NO2, small particulate (PM 2.5) air pollution, and other pollution concerns. 

Alert to a PR disaster in the making, especially in the wake of serial landmark reports linking PM2.5 pollution to increased incidences of death from heart disease and lung cancer, the fossil industry moved from internal rumination on the problem to outright attack on those who dared raise the issue in the public eye. 

After a scientist in the pay of the American Petroleum Institute (API) testified at a congressional hearing in 1997 that the connection between air pollution and death rates was “weak”, The Guardian says, ExxonMobil churned out its own study, finding “no substantive basis” for any connection between PM2.5 and higher mortality.

Confirming a pattern familiar to many public health advocates in America, Carroll Muffett, chief executive of the Center for International Environmental Law, told The Guardian that fossil companies “in all likelihood” consulted with a fellow traveller in the quest to bury public health concerns—namely, the tobacco industry. 

Muffett also drew a direct line between the revelations about what Big Fossil did to suppress evidence of its responsibility for poisoning the air we breathe to companies’ responsibility for delaying action on the climate crisis. 

Meanwhile, in a major finding in February, The Guardian reports that “a team of U.S. and UK researchers calculated that nearly one in five of all deaths worldwide each year is due to particulate pollution, a stunning death toll that is greater than that caused by HIV/AIDS, malaria, and tuberculosis combined.”

Noting that “about 350,000 of these deaths occur annually in America,” The Guardian adds that “while overall pollution trends have improved in recent decades in the U.S., pockets of stubborn pollution remain, often concentrated in poorer communities, among people of colour and those living in the Rust Belt.”

Harvard biostatistician Francesca Dominici pointed to “very consistent and solid evidence across many countries of the link between fine particulate matter and harm to health.” She called for “stricter regulation” against this “very harmful” pollution, noting “a ton” of evidence that “lots of people are dying in the U.S. from exposures even below the current limits.” 

Dominici, co-author of a 2020 study that drew a clear connection between air pollution and COVID-19 mortality, knows just how likely the fossils are to push back hard against any regulation. While her study merely presented preliminary findings, the attacks against it were “very hard and very stressful,” and included “scare headlines and erroneous media reports.” 

Big Oil’s pushback grew particularly vociferous under the Trump administration, The Guardian notes, flagging the API’s 2017 demand that the U.S. Environmental Protection Agency “relax standards around nitrogen dioxide—a pollutant linked to asthma in children and higher mortality in adults from heart disease and cancer—claiming there was no proven association with harm and existing rules were ‘more stringent than necessary’.”

George Thurston, a New York University environmental health expert who co-authored a landmark 1987 study on the dangers of fossil fuel combustion, has long been tracking fossil efforts to prevent regulation, along with the stream of industry-funded studies disputing or even disparaging scientific research. 

“Their goal is to undermine the scientific method, science itself,” he told The Guardian.