Whether Cairo is officially the most polluted city on the planet, or whether it ranks somewhere in the top three, doesn’t really make a difference for its 20 million residents. When they breathe (short breath, short breath, just what’s strictly necessary), they inhale a nasty assortment of dust, soot, fumes and other volatile compounds that lodge themselves deep in their lungs and swim in their bloodstream.
Even if Delhi, perhaps, or Beijing, maybe, should top the list, it does not change the fact that walking Cairo’s busy streets or being stuck in traffic makes your eyes itch, your stomach turn and your head dizzy. It’s possibly louder elsewhere, but that doesn’t change the reality of extreme noise across the city. Apart from a few hours’ respite on Friday mornings, people’s ears are continuously assaulted by car horns, shouts, trucks cruising at full speed and construction works sprouting on every street corner.
At night, there is no Milky Way to be seen, just a couple of solitary, incredibly stubborn stars on a gray gradient of a night. What should be an enchanting spectacle is chased away by the glare, a vast shield formed by buildings, billboards, shops and street lights. It’s relentless. It’s exhausting. It’s extremely bad news for people’s health.
Of course, officials from the Environment Ministry are upset. They are upset because they have been trying to make a terrible situation a little less terrible. For example, they came up with incentives for farmers to stop burning rice husks at the end of the harvest. As a result, last year’s blanket of smoke enveloping Cairo had thinned out noticeably. They have pushed for buses and taxis to use natural gas as fuel to curb transportation-based CO2 emissions. And for the past week, they have been contesting this ranking on live TV, in newspapers and in statements to the press. Of course, they don’t want Cairo to carry around this sticky label of the most polluted city. And to be fair, it probably isn’t. But let’s look at this ranking for a minute.
What immediately jumps out as interesting is the choice of pollution categories that are represented. It’s not common to include noise and light pollutions, and even more unusual to consider them on par with air pollution in terms of importance. Noise and light, especially in this part of the world, are considered annoying, disturbing and a nuisance. But a source of pollution? Not so much.
If we look at how Cairo fares in each category of pollution, it does very poorly in every single one. It’s either the second worse or the third worse — according to the Eco Experts’ data contested by the Environment Ministry.
Air pollution? Cairo’s fine and coarse particle levels in the air are roughly 12 and 14 times over the World Health Organization’s safe limit, respectively. Fine particles of a diameter equal or smaller to 2.5 micrometers are the most dangerous: their small size — about 30 times smaller than the width of a human hair — and light weight enables them to be suspended in the air for a very long period. And because they are so tiny, they are easily inhaled and cause serious health complications. In the competition for poorest air quality, only Delhi outranks Cairo.
A peer-to-peer study, published on August 20 in Environmental Science & Technology Letters, found that air pollution alone shaves 1.85 years off Egyptians’ life expectancy on average.
Delhi also wins noisiest city, and Cairo falls right behind, with a score of 1.7. This “noise score” is comprised between 0 and 2, with 2 being deafeningly bad. High noise levels can increase cardiovascular diseases across the population, affect children’s physical and psychological health and impair their ability to learn.
Who are the biggest Milky Way slayers? Moscow and Chicago beat Cairo to it. Calculated in candelas per square meter (μcd/m2), Cairo’s level of artificial light-related pollution has been estimated at 14,900 μcd/m2. This means that the Cairo night sky is 85 times brighter than the natural color of the sky. This disturbs our circadian rhythm and sleep quality, confuses nocturnal animals and deregulates plant growth by tricking them into thinking that night is day.
But why is Cairo so polluted, and why is it on this scale? As far as air pollution is concerned, not all the responsibility can be traced to anthropogenic causes. Egypt’s geography and the capital’s topography are contributing to Cairo’s pollution predicament. Because Cairo is squeezed on a narrow strip of land, flanked by desert on both sides, copious amounts of dust, sand and coarse particles are swept off the ground by the wind and deposited inside people’s living rooms, cars and nostrils. The rare and brief rainy episodes can only immobilize a very limited percentage of the particles that float about. The dust, mixed in with car and factory exhaust in a toxic whirlwind, struggles to escape the city’s grasp, blocked on one side by the Moqattam hill, and accumulates in narrow streets or under bridges. In Cairo, trees are cut down to make way for new buildings and to widen streets, even though they can soak up large amounts of carbon dioxide.
Improving certain aspects of Cairo’s urban planning by replanting trees, eliminating unnecessary city lights and refocusing street lights — to face the ground and not the sky — could go a long way, and increase quality of life for Cairenes noticeably. The Environment Ministry has neither the power nor the means to reduce Cairo’s pollution levels in a significant enough way on its own, and should be getting all the support it needs from other ministries and industrial players.
Seeing Cairo labeled as the world’s most polluted city should be seen as a call for action. Let’s not waste time contesting it isn’t. It’s bad enough.