Scientists Identify How Particulate Pollution Triggers Lung Cancer

Scientists have discovered the connection between car fumes and lung cancer. The new study uncovered how fine particulate matter smaller than 2.5 micrometers, known as PM2.5, triggers lung cancer in people who have never smoked.

"The same particles in the air that derive from the combustion of fossil fuels, exacerbating climate change, are directly impacting human health via an important and previously overlooked cancer-causing mechanism in lung cells," said Charles Swanton, lead author and the chief clinician of the Francis Crick Institute and Cancer Research UK, said in a statement. "The risk of lung cancer from air pollution is lower than from smoking, but we have no control over what we all breathe."

One could argue with the last part of that statement. Of course, we have control over what we breathe—it is the same problem that we have with climate change. We know what to do. It's just inconvenient and there are powerful forces preventing it.

As climate journalist Amy Westervelt wrote in The Guardian after the latest United Nations' Intergovernmental Panel on Climate Change report was released: "The technologies and policies necessary to adequately address climate change exist, and the only real obstacles are politics and fossil fuel interests." The same is true with PM2.5.

Let's look for a moment where PM2.5 particles come from. PM2.5 emissions are barely regulated and were not well-known until recently—we have been swimming in them for years. Russell McLendon noted for Treehugger, "People have been choking on manmade air pollution for roughly half a million years, ever since Pleistocene cavemen huddled around the first campfires."

In more recent times, we have been lost in a miasma of cigarette smoke, home heating, industrial emissions, and car exhaust. As smoking and coal use declined, other data points popped out.

Previous research found that PM2.5 was responsible for 18% of global deaths in 2018. Joel Schwartz, a co-author of the report, said: “Often, when we discuss the dangers of fossil fuel combustion, it’s in the context of CO2 and climate change and overlook the potential health impact of the pollutants co-emitted with greenhouse gases. We hope that by quantifying the health consequences of fossil fuel combustion, we can send a clear message to policymakers and stakeholders of the benefits of a transition to alternative energy sources.”

As with carbon dioxide emissions, much of particulate matter (or particle pollution) emissions come from cars, with the majority of it coming out of the exhaust pipe. But there are two other major sources of particulate matter from cars and trucks:

1. Abrasion: the particles emitted from brake and tire wear
2. Resuspension: the kicking up of particulate matter back into the air by wind and cars rolling over them

This is hugely controversial. When I first covered a study concluding that these were directly proportional to the weight of the vehicle and, therefore, electric cars would be worse than ICE-powered cars, the outrage in comments almost crashed the site and I had to apologize. Then the Organization for Economic Cooperation and Development (OECD) came to the same conclusion, writing in its report, "EVs do not necessarily emit less PM2.5 than ICEVs. Although lightweight EVs emit an estimated 11-13% less PM2.5 than ICEV equivalents, heavier weight EVs emit an estimated 3-8% more PM2.5 than ICEVs."

This time I did not apologize and wrote: "To reiterate: this is not an indictment of or a rant about electric cars. No matter how they are powered, we need fewer, lighter, and smaller cars, particularly in our cities." Now there is even a stronger case for this.

As with climate change, there are particulate skeptics who downplayed the links between particulates and disease, including the former head of the EPA. The clear scientific links were not there, and as Swanton told The Guardian, “Air pollution is associated with lung cancer but people have largely ignored it because the mechanisms behind it were unclear.”

But now it is clear: "In the laboratory studies, the Francis Crick Institute scientists showed that the same pollutant particles (PM2.5) promoted rapid changes in airway cells which had mutations in EGFR and in another gene linked to lung cancer called KRAS, driving them towards a cancer stem cell like state."

Everything changes when the link is confirmed—look what happened when the link between smoking and lung cancer was found. And now that we know that burning fossil fuels—and another major source of PM2.5, wood—is linked, we can approach the problem the way we did with smoking.

As I wrote in my book, "Living the 1.5 Degree Lifestyle":

"Forty years ago, almost everyone smoked, it was socially acceptable, and it happened everywhere. Governments applied education, regulation, and taxes. There was a lot of social shaming and stigmatizing happening too; in 1988, medical historian Allan Brandt wrote, “An emblem of attraction has become repulsive; a mark of sociability has become deviant; a public behavior now is virtually private.” Instead of virtue-signalling, we had vice-signalling. Fossil fuels are the new cigarettes. Their consumption has become a social marker; look at the role pickup trucks played in the 2020 American election. Like cigarettes, it is the secondhand externalized effects that are the motivators for action; people cared less when smokers were just killing themselves than they did when secondhand smoke became an issue."

Fossil fuels are the new cigarettes. If we can't ban them, we can at least regulate them, tax them, and maybe even stigmatize them. They are not just warming the climate—they are killing us.