A smoggy Olympic stadium. (Photo via)
As of 2010, more than half of the world's population lives in an urban area. According to the World Health Organization (WHO), by 2030, six out of every ten people will live in a city. By 2050, this proportion will increase to seven out of ten people. And cramming humans—with all of their waste, cars, and other stuff that pollutes and destroys the environment—together into such relatively cramped spaces has its repercussions. That beautiful sunset you saw? Light pollution. The new species of fish swimming around the fountains in Central Park lake? A featherless pigeon that was dropped out of the sky after asphyxiating on noxious power plant gases.
The good news is that scientists have just found a new side effect of cities for us all to worry about. The specialized cancer agency of the WHO, the International Agency for Research on Cancer (IARC), published a report this week that classified outdoor air pollution as carcinogenic to humans. According to the findings, the polluted air in our cities is putting us at risk of lung and bladder cancer, and their conclusion has some morbid endorsement. In 2010, there were 223,000 deaths from cancer worldwide as a result of pollution.
"The air we breathe has become polluted with a mixture of cancer-causing substances," says Dr. Kurt Straif from the IARC. "We now know that outdoor air pollution is not only a major risk to health in general, but also a leading environmental cause of cancer deaths."
In the US, The Clean Air Act of 1970 helped curb the dense visible smog that was looming over major American cities, and put strict industry regulations in place in order to combat our rapidly depleting stratospheric ozone layer. In New York City, pollution accounts for six percent of annual deaths, and although it commonly ranks first as the dirtiest city in America, it doesn't even contend internationally.
Maybe we should all start wearing these (Photo via)
According to the IARC's report, the predominant sources of outdoor air pollution are transportation, industrial and agricultural emissions, stationary power generation, and residential heating and cooking.
"Classifying outdoor air pollution as carcinogenic to humans is an important step," says IARC director Dr. Christopher Wild. "There are effective ways to reduce air pollution and, given the scale of the exposure affecting people worldwide, this report should send a strong signal to the international community to take action without further delay."
Dr. Dana Loomis, deputy head of the IARC monographs section, says that, "The results from the reviewed studies point in the same direction: the risk of developing lung cancer is significantly increased in people exposed to air pollution." This means that if you live in a city, or even if you just spend some time in cities, you are at risk from air pollution.
This may not be a startling revelation, but the classification of outdoor air pollution as "carcinogenic" is an indication of how bad pollution has become worldwide, while also hopefully being a wake-up call to those in power. What the report also points to is that, inevitably, economic growth and industrialisation in parts of Asia, South America, and Africa have gone hand in hand with an increase in pollution. I got in touch with Dr. Loomis to talk about the IARC’s report a little more.
VICE: Which cities are particularly badly polluted? How many different cities were evaluated?
Dr Dana Loomis: As part of this evaluation, we collected available data on pollution levels around the world. This is too extensive to list here, but in brief the most polluted cities now are in Asia, South America, and Africa. However, there are important variations in the level of pollution. Full details will be in the monograph, but it won't be published for another year.
Has pollution gotten worse in major cities?
The overall level of air pollution in cities with strict regulations is much lower than 30 to 40 years ago, but the improvement hasn't been equal for all places and all pollutants. The increase in diesel-powered vehicles is a complicating factor that has led to slower declines in NO2 levels and may have increased the amount of carcinogenic material emitted to the air.
**Is the air going to become more carcinogenic? ** Not necessarily. Pollution levels in most of Europe and North America have been reduced substantially as a result of controls imposed since the 1970s, and further reductions are already under discussion. The most important challenges today are in the new industrializing countries, such as India, China, Chile, and Brazil. Some of those countries are already taking steps to control air pollution.
What can we do about how polluted our cities are becoming?
Air pollution is first and foremost a public health problem, in the sense that the air belongs to everyone but no single individual controls it. Air pollution has to be addressed by collective action at local, national, and international levels. The role of IARC is to provide scientific information, like this evaluation, as a basis for taking appropriate actions.
What can individual citizens do to protect themselves from this pollution?
Unfortunately, not very much.
Are our cities killing us?
The health issues arising from air pollution are significant and should be taken seriously, but it's important to keep them in perspective. The risk of lung cancer associated with air pollution at the levels now existing in advanced developed countries is now comparable to passive smoking. And that's important enough to take action.
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