Toxic smoke from raging fires in Canada continued to impact large swaths of eastern North America Thursday. Overnight and into the morning, air quality deteriorated to record-shattering levels. In Lancaster, Pennsylvania, the hourly Air Quality Index peaked at 491 Thursday, far surpassing the threshold of 300 considered “hazardous.” In Philadelphia, monitors topped out at 425 overnight, while in the Washington D.C. area, levels reached 315 just in time for the morning commute.

Lower but still highly dangerous levels of smoke prevailed throughout much of the East Coast and Midwest. Officials issued air quality alerts in more than a dozen states Thursday. In New York City, air quality was rated at “very unhealthy” or “unhealthy” levels much of the day, down from the extreme conditions prevailing 24 hours before.

The experience in the New York metropolitan area, the largest in the US and home to more than 20 million people, testifies to the unprecedented intensity of the current wildfire disaster. Air quality was degraded since early in the week, with an acrid, campfire-like scent detectible as early as Monday. By Wednesday, however, what was unfolding resembled a surreal scene straight out of a science fiction film. Around 2:00 p.m., the thick, greenish-gray fog transformed into Armageddon orange. The sky darkened, and a chill set in as the smoke scattered the sun’s light and heat. The ordinarily busy Manhattan streets began emptying.

Air monitors crossed the “hazardous” threshold for the first time since the modern monitoring network was established. The scent, which took on an increasingly stinging character, was perceptible even indoors. The noxious air caused lungs to burn, triggered headaches and irritated eyes. Other, far more severe and lasting maladies, including severe illnesses and deaths, remain to be tallied. But public health researchers know such outcomes are inevitable.

Fine particulate matter found in wildfire smoke is known to have serious impacts on the respiratory system, from triggering asthma attacks to lung cancer. The tiny particles can also penetrate the bloodstream and cause damage to vital organs, including the heart and brain. Even short-term exposure at such levels can mean lasting damage, especially in children and other vulnerable populations.

Despite the known risks, schools in New York City remained open Wednesday at the peak of the disaster. Children and teachers peered out of classroom windows onto a cloud of glowing orange. In schools across the city, educators and students reported unbearable air inundating their buildings, many of which are dilapidated structures with no ventilation system upgrades even after three years of the pandemic. As schools let out, the Air Quality Index rose above 400.

Officials across the region replicated the criminal indifference to children’s health in New York City on Wednesday. Philadelphia and Washington D.C. public schools remained open during their cities’ hazardous peaks on Thursday.

Like schools, most businesses refused to prepare for the extreme conditions enveloping the region. There was no pause in construction, package delivery, transit service or many other jobs that left workers highly exposed. The back-to-the-office push led by figures such as New York Mayor Eric Adams meant that many office workers who could just as easily work remotely were forced to commute in dangerous conditions.

In the absence of any coordinated response, residents were forced to take action on their own. On Wednesday morning, N-95 masks were already a fairly common sight in the city, though by no means ubiquitous. By the afternoon, those with extras on hand were passing them out to colleagues, friends or passersby in need.

Much of New York City shut down on its own by late afternoon. Usually bustling shopping streets in the boroughs went largely vacant. Subway cars during the evening rush were half full. Many evening events were canceled, sometimes more out of necessity than forethought. The Broadway show Prima Facie, for example, ended just 10 minutes after it began, as star Jodie Comer was overcome with breathing problems.

In cities across the region, workplaces were only shuttered when it became apparent that not enough employees were willing to risk their health to come to work.

The refusal of officials to prepare for such a disaster, despite warnings made by scientists about the increasing danger from intensifying wildfires, mirrors the inaction taken with the onset of the pandemic. Then as now, the driving policy considerations were placating the immediate economic concerns of businesses regardless of the risk to public health. Only now, Eric Adams, Kathy Hochul and Joe Biden sit in the chairs once occupied by Bill de Blasio, Andrew Cuomo and Donald Trump.

The present levels of air pollution are unlike anything the area has seen in decades, if ever. While more than 117 million people across the country, including all of the New York metro area, live in areas that do not meet federal air quality standards, the bad old days, where persistent smog and other air pollutants rose to crisis proportions, were thought to be a thing of the past. New York City has not experienced anything approaching the scale of the current disaster since before the advent of modern pollution controls.

Now, even as most high-polluting heavy industries, once located in cities like New York, have shifted overseas, climate change is driving a return to shocking levels of air pollution. The fires raging in Quebec are just the latest in a string of extreme events erupting across the globe. Population centers once spared are now confronted with new deadly threats.

With global capitalism on a trajectory to blow through the targets set to limit catastrophic warming, the deadly fog over much of the eastern United States is a harbinger of what is to come. The only viable way forward to protect human health and limit the climate catastrophe is a struggle of the working class to take power into its own hands and reorganize society based on human needs, not profits.