The air you breathe is killing you. I know this because I am investigating the state of our air, looking at data for air quality across the whole of South Africa. Things are much worse than the government and companies let on.
We’ll start publishing that investigation next week. This week, I want to share the results from two months of testing my own air. That’s how long I have been carrying around a personal air quality sensor — strapped to my bag, sitting on my desk at the Mail & Guardian or hanging out of my window at home.
The sensor, the size of a small coke can, has small holes through which it sucks in air. Its onboard laboratory then tests the concentration of four main pollutants: nitrogen dioxide, volatile organic compounds and small and big dust particles. These tend to end up deep inside your body when you inhale. For children, lower to the ground and breathing more and more deeply, this pollution has its greatest impact. The smaller the particle, the further into your body it goes. PM 2.5 — the smallest dust particles — for example gets into your blood vessels and starts to break them down. If you’re old and your body is worn down, those vessels are already weak to start with.
The World Health Organisation estimates that dirty air kills seven million people each year — 20 000 of those deaths happen in South Africa. Half die because of indoor pollutants and half because of pollution happening from things such as factories and cars.
Tracking down the sources of that pollution, or even just knowing how dirty your air is, turns out to be really difficult. In South Africa, companies collect the data to show that they are in compliance with air quality laws. But all sorts of small-to-medium companies just don’t and there is little capacity to enforce laws. National government and municipalities have their own network of sensors, which feed into the air quality information system — you can check the results on a public website. These sensors either don’t work (in Johannesburg one station closed when everything in it was stolen) or the data set is intermittent, so the information is of little use.
This lack of data means people have to find other ways to record air pollution. Some communities, such as Riverlea in Johannesburg, use empty buckets to collect dust as a crude measure of how much dust is blowing over homes thanks to mining. Others, like Boipathong in southern Gauteng, have NGOs that are starting to roll out their own sensors.
My sensor comes from Plume Labs, a French startup that’s trying to create a global database of air pollution. The M&G has partnered with Plume for our larger investigation into air quality. These kinds of sensors are still in their infancy, and are better at showing trends in air pollution, rather than exact figures for how bad the air is. They are, however, getting better with each new generation of sensors.
Checking the results from the sensor — which are collated in an app that shows the average level of pollution throughout the day — has become somewhat of an addiction. Green means things are good. Orange and then purple mean the air going deep into my lungs is making me sick. Orange-to-purple is the dominant colour theme.
The fact that we’re sucking in dirty air all the time is counterintuitive if you live in Johannesburg. We pride ourselves with having one of the biggest urban jungles in the world. From the eighth floor, where the M&G has its offices, the view tends to be of a milky blue sky and green trees. Trees suck up pollution. They make our air clean. But to drive into Johannesburg is to descend into a thick layer of dirty grey air, which hangs over the metro like a dome. Cape Town and Durban are no different. If you fly into Johannesburg you’ll see a thin yellow band of ozone and sulphur pollution hanging over the city.
All this trickles into my home. Over the two months that I have been using my sensor, certain patterns have emerged. On most days, the concentration of nitrogen dioxide is dangerously high from mid-morning until sunset. In cities with lots of cars, this is normally the single worst pollutant. Major metros, such as Paris, have brought in heavy taxes on cars to try and get this pollution out of the city. London has banned diesel-powered ice cream vans because of their constant polluting in neighbourhoods. My home is next to the main road in and out of the neighbourhood: many cars mean lots of exhaust fumes drifting into my lungs.
At night, the concentration of dust particles starts to climb to the point where my sensor is spitting back dark purple results. Dust on the highveld is ubiquitous, thanks to the dry ground and wind. It’s exacerbated by people burning wood and coal for cooking, and to stay warm. This particular problem is why Eskom says that getting electricity into homes so people don’t have to use coal or wood is crucial for tackling air pollution. This Sunday, at 1am, the level of dust pollution was so high that my app warned that it “exceeds the World Health Organisation limit for one hour”. That means that breathing in the air for more than one hour has long-term health impacts. This ranges from asthma to heart attacks.
Things aren’t much better at work. Our office is in a large building, with a centralised system for heating and cooling air, which is then pumped around. The air is sucked in from outside, with all its pollutants. Because we’ve just moved in, there is a constant, and unsafe, level of pollution from volatile organic compounds — those are the chemicals released as the glue and chemicals in new furniture, dry walls and blinds break down.
Outside, when I go to the shop or walk down the street, the level of pollution climbs and stays at dangerous levels. Each breath means all these particles finding their way into my lungs, and then around my body. And, when I exercise, deeper and faster breaths mean more pollution.
While giving life, each breath is also shortening my lifespan.