Fatal Fog
When clouds kill
It was somewhere between Tuskahoma and Talihina Oklahoma where I became carsick. It was also on this particular October morning that I became intimately familiar with smog. As I sat in the sunny backseat of the family Plymouth watching the rolling hills dotted with small farms, barbed wire fences, and grazing cattle fly past, my stomach began to rebel. Not even the billboard advertising pecan logs looked appealing.
It wasn’t long before a bologna sandwich, smeared with tart yellow mustard, the crust neatly cut off, and wrapped in brown wax paper was passed back from the front seat. Mother lit up another cigarette, the radio played Patsy Cline, and miles went by with the sandwich in my lap uneaten. And then the nail in my digestive coffin arrived. A Farmall tractor appeared on the approaching rise of the little two-lane highway, clouds of sooty black smoke belching from the tailpipe with each change of gear.
I could hear the sigh from my father as we slowed to a crawl behind the shiny red behemoth. It would just be a matter of waiting until the thing turned off somewhere ahead or the road flattened enough for passing, but this was 1958 and sitting behind a slow vehicle wasn’t just an inconvenience — it was a ride through a gray haze of toxic soup. As we crept along, the car gradually began to fill with a cloud of diesel exhaust and cigarette smoke — a nauseating, foul fume that made my eventual resignation to the whims of my stomach inevitable. But inhaling fumes while trapped in traffic behind cars that gush black clouds of exhaust was just everyday life. Despite my tender age, I knew something about breathing this noxious mess was wrong — unhealthy…
Smog in the 1950s was as ubiquitous as poodle skirts and Jell-O molds in unnatural colors. Until the Clean Air Act of 1963, United States federal action on the matter consisted of funding research and acknowledging the hazard air pollution poses to public health. Things really began to change when Richard Nixon (yeah, I know, go figure — on the surface Watergate dude didn’t seem like a champion of the environment, but there you are) formed the Environmental Protection Agency in 1970 which placed the might of the federal government behind national legislation.
In the UK, addressing smog was a result of several particularly bad smog events that caused thousands of premature deaths of susceptible people. The infamous London ‘pea soupers’ of the 1940s, 50s and 60s precipitated public outcry and finally substantive government action to address the horrendous air pollution that persisted over London and other industrial cities in the UK. Once again, we see that the criteria for doing something about a problem requires a body count.
The UK government introduced its first Clean Air Act in 1956, most likely in response to the massive smog event to be discussed in this article, the Great London Smog of 1952. Then in 1961 the National Survey was established. It was the world’s first coordinated national air pollution monitoring network monitoring black smoke and sulfur dioxide at approximately 1,200 sites in the UK. Subsequent pieces of legislation and additional monitoring networks were introduced to combat and measure air quality that expanded the data collection to include fine particulates, ozone, and other vehicular emissions.
Studies over the years have confirmed that smog is responsible for a range of respiratory diseases, including cancer; it increases the likelihood of birth defects and kidney disease; and may contribute to the development of Alzheimer’s. Using a new global model, research by a team of scientists from Germany, Saudi Arabia, and the UK suggests that breathing polluted air reduces life expectancy by an average of three years.
A Little History
For those who have spent their entire lives isolated somewhere in the Arctic or in a remote cave, I shall pause here and give a short explanation of what this special version of fog is. A short definition of smog is air pollution caused by human activities with burning coal, factory emissions, and vehicle exhaust as the largest contributors. The term ‘smog’ is a combination of the words smoke and fog and has been a byproduct of human thoughtlessness since well before the Industrial Revolution began around the 1780s.
In our quest to stay warmer and comfier than every other species, heedless polluting has a long and lustrous history. Indeed, evidence of air pollution can be traced as far back as Neolithic man, whose campfire soot can still be seen coating the insides of caves and whose mummified remains still bear the black deposits from smoke. Ancient Egyptian mummies also exhibit lung damage from air pollutants. From the Himalayas to ancient Rome to the 1868 Meiji Restoration in Japan, people around the world have long been well on their way to mucking up everything.
Our propensity for polluting continued with the advent of organized mining operations once ancient peoples discovered how useful metals, minerals, and other underground goodies could be. Two-thousand-year-old court records from ancient Rome include complaints about smoke and metallic pollutants with the residents of the city referring to their smog as gravioris caeli or ‘heavy heaven’ and writing about ‘clouds of ashes’ and ‘poisonous fumes’. In 1257, Queen Elanor of England wrote of her distress over the noxious smoke produced by the nearby coal fires burning in Nottingham stinking up her castle. From Conquistador silver mining to Victorian coal production, the ways we’ve found to befoul the air is varied and dangerous to our health.
“But ’tis so. I know ’tis, as I know the heavens is over me ahint the smoke.” — Charles Dickens, Hard Times (1854)
Of course, when the population of the planet was significantly smaller, the ceaseless mining and coal burning wasn’t such big a problem until everyone got busy and cities blossomed into concentrated cauldrons of toxic stew. But by the time the Industrial Revolution began, with its large-scale factories, steam engines, and coal burning fireplaces, smog was so pervasive that Charles Dickens wrote of it in his books. In an exchange between characters in Hard Times (1854) he writes, “But ’tis so. I know ’tis, as I know the heavens is over me ahint the smoke.” And in the opening chapter of Bleak House (1853) he describes fog coming “down the river, where it rolls defiled among the tiers of shipping, and the waterside pollutions of a great (and dirty) city”
Then the 20th century arrived with its fancy cars, assembly lines, and appetite for energy and here’s where things began getting really weird.
Several instances of fatal smog, such as the 1948 Dorna, Pennsylvania event, can be found in the first half of the 20th century. The 1940s was the decade when Los Angeles had its first eye-stinging event in 1943. Being on the west coast and in the midst of World War II, the ensuing panic can be excused when after smog formed over the city so densely, the residents thought that Japan had launched some kind of chemical attack. But it is the great London smog of 1952 that is the case study examined in this post. Five days of unusually heavy air pollution that escalated to deadly levels, hospitalizing 150,000 and taking the lives of between 8,000 and 12,000 people.
The Setup
On December 5th, 1952 Londoners awake to a crisp day. Nighttime temperatures have been consistently in the lower 20s (F) at night and into the mid-30s during the day for several days thanks to an ongoing cold snap. With the cold weather, morning coal fires are stoked in homes, rush hour begins, and factories commence the daily belch of soot. The skies at this point are clear. A persistent high pressure system is still lingering off the coast to the west over the Atlantic keeping the weather chilly but nice.
However, the blue skies above southern England contain an invisible key ingredient in what is about to happen. An inversion has setup during the night. Warm air aloft is trapping stagnant, cold air at the surface — air that includes the usual cocktail of pernicious manmade emissions: carbon monoxide, nitrogen oxides, ground-level ozone, and sulfur dioxide. The radiation inversion begins to strengthen during the morning, raising the dewpoint, and tightening the cap over the layer of ever increasing pollutants at ground level. Winds remain calm and without a breeze, the upcoming five days is soon to become a choking nightmare.
With the help of the inversion as well as London’s cars and factories, a normal radiative fog is hour by hour shifting into a deadly, suffocating smog.
As the day progresses, a cold fog forms. Nothing unusual for London which is noted for its famous fogs but this is turning into something quite different. The overabundance of dust particles and soot give droplets of water something on which they can cling. As Big Ben and the Tower Bridge slowly disappear inside a diaphanous veil, the usual grey mist begins transforming into a sickening shade of brownish-yellow — ‘Baby’s First Summer’. With the help of the inversion as well as London’s cars and factories, a normal radiative fog is hour by hour shifting into a deadly, suffocating smog.
By the afternoon, river traffic on the Thames has come to a complete stop, commuter trains are cancelled, and flights grounded. All forms of public transportation are halted except for the stalwart Underground and limited bus service, with double-deckers being led about by conductors with flashlights walking ahead. By December 8th, buses and trolleys will have ceased to run altogether. Long distance trains going into and out of London to other parts of England are running on a limited schedule. In the days to come, routes will be cut back even more.
Cars, too, are soon being abandoned or are inching their way along streets with drivers hanging out of the windows to see into the gloom. Pedestrians fare no better. Residents can no longer see their feet as they walk and as the oily soot begins to cling to the sidewalks and pavement, pedestrians slip on the thin greasy coating. Anyone caught outside is soon covered in a sooty black ooze — the same substance that is starting to line the inside of their lungs. London is about to become a very dark and dangerous place.
The fog was so dense that with police cars immobilized, most ‘999 calls’ were being answered by officers on foot who were often confronted by gunmen.
Hell in Cloud Form
From that evening on until the smog cleared, criminals took advantage of the murk. Shop windows were broken in ‘smash and grab raids’, and looting became common. Purse snatchings and muggings were rampant with the hapless victims being caught unaware save for ‘ominous footsteps’ emerging from the mist. The Daily Mirror reported on December 6th, only one day into the event, of a man on a motorcycle striking women and stealing handbags, two men battered a woman in Neasdon before taking her valuables.
According to the December 8th Coventry Evening Telegraph, the fog was so dense that with police cars immobilized, most ‘999 calls’ were being answered by officers on foot who were often confronted by armed gunmen. Armed robberies skyrocketed during the event. Common targets were theatres, shops, and post offices with anywhere from one to three gunmen involved. As the tabloid newspaper (before tabloids were more interested in reporting about lizard people and alien babies), The People, wrote on December 7th, “A terrifying new wave of crime hit London last night as the gunmen and ‘cosh’ boys cashed in on the ‘worst-ever’ fog which blacked out the capital.” The blackout was being compared to the Blitz by people who had just a few years before had lived through the strict blackout rules and weeks of nightly bombing. Over the life of the event, hundreds of crimes were committed, and the spree lasted as long as the dark reigned, throughout the entire five days.
But purse snatchings and disruptions in travel weren’t the worst aspects of the smothering smog. Londoners quickly realized they were slowly being choked to death. Breathing soon replaced transportation as a priority as hospitals became overrun with patients in respiratory distress. Ambulance service was severely crippled and arrangements for transporting patients were much the same as with buses where men walked in front as guides. The number of deaths during the week of The Great Fog, as it became known, would eventually total well over 8,000 with subsequent studies[1] done years later estimating the total to be more likely closer to 12,000. Insidiously, the deaths would continue for weeks long after the smog had dissipated.
Aftermath
Doctors at the time were unsure about the exact mechanisms behind the deaths. In an interview with the Daily Mail on December 12th (published on the 19th), three days after the smog had dissipated, Dr. Earnest Wilkins with the Atmospheric Pollution Section of the Department of Scientific and Industrial Research said, “We do not know the precise agent in fog that acts as the killer. It may be the carbon that clogs the lungs. It may be the oxides of sulfur.”
We now know which problematic ingredients in smog kill or debilitate. But through the years as pollution regulations improved, many of the chemicals involved have become less prevalent as their percentage in the mix has decreased. In other words, the components of your smog may vary. The following list describes the components of air pollution and their effects on health.
Particulate matter, which is made up of solids and liquids, can vary in both size and chemical composition. If smaller particulates reach the lungs, they can cause damage which in turn leads to infections, bronchitis, and emphysema.
While essential at high altitudes, ozone (O3) at ground level is a major component of smog and a dangerous health hazard. It forms from a chemical reaction between nitrogen oxides and volatile organic compounds (VOCs) in the presence of heat and sunlight. Emission sources range from factories and refineries to cars and trucks. Symptoms of exposure to ozone include wheezing and coughing; difficulty breathing; painfully irritated eyes and nose; and a feeling of burning in the lungs. Prolonged exposure can result in damage to the eyes and respiratory system. The irritated cells are replaced after exposure, but replacement cells can often be malformed leading to premature aging of the lungs and other complications later.
Probably the best known ingredient in smog is carbon monoxide (CO), dear to our hearts since it comes primarily from one of the things humans love maybe even more than each other — cars. But as much as we are attached to our metal, pollution-spewing pets, it’s painful to admit that in high concentrations CO is deadly. It binds with hemoglobin in the blood, reducing its ability to carry oxygen thereby starving vital tissues of oxygen. People with compromised immune systems and preexisting conditions are most vulnerable to CO exposure. Legislation over the years has also significantly reduced the emissions of carbon monoxide, especially from combustion engines, helping high congestion areas such as LA and New York City.
Nitrogen oxides (NOx), which plays a significant role in the formation of ozone, is a lung irritant and lowers resistance to infection. Nitrogen dioxide along with aerosols give smog the distinctive reddish-brown color and is emitted by power plants and combustion engines. Symptoms from even short-term exposure include coughing and shortness of breath, but high concentrations of NO2 are highly toxic and can lead to serious lung damage.
Sulfur dioxide (SO2) is a major contributor to the formation of small particulate matter which leads to eye irritation, shortness of breath, respiratory illness, and impaired lung function. As discussed previously, small particulates can penetrate deeply into the lungs, and when combined with water converts to sulfuric acid. Sources of SO2 are the burning of fossil fuels, smelting, and diesel vehicles. Recently, regulations have reduced the concentration of NO2 and sulfur in fuels, but back in 1952 that wasn’t the case. We will see how the unrestrained emissions of both NO2 and SO2 contributed to the deadly London event.
So why was this particular smog event so lethal? Researchers at Texas A & M have finally discovered the chemical process that lead to the development of the toxic cocktail that killed thousands that week in December of 1952. Their results show that nitrogen dioxide, a byproduct of coal burning, which occurred initially within the natural fog was a key ingredient in the conversion of sulfur dioxide to sulfate. The sulfate in turn produced smaller sulfuric acid particles, the evaporation of which covered the city in an acidic haze.
In the end, after a government investigation which precipitated the clean air legislation that was passed in 1956 as well as the transition away from coal as the London’s primary heating source, air quality began to slowly improve. But this transition took years, and during that time deadly smog events continued to occur, such as the one that killed about 750 people in 1962. Sadly, air pollution is still killing people today. Much more stringent regulations are needed but more important than that is finding the will to place the well-being of humans above profit or convenience or stubbornness.
[1] link behind paywall but synopsis available
