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How to interpret air pollution?

One of the citizen’s sustainocratic initiatives that we initiated in Eindhoven (Netherlands) is the co-creation of the healthiest city of the world using air quality as guiding principle. We invited the local government, business enterprises and scientific researchers to take responsibility with us. That is how the formal Local AiREAS Eindhoven was born in 2011. Air pollution is one of the most deadly problems that we face in the world. Since mid October this year the World Health Organization recognised it to be level 1 cancer producing.

Now what? How do we deal with it as a citizen’s cooperative with institutional memberships? We seem to know that pollution comes from high level concentrations of burning stuf (fuel, wood, waste, etc) but our entire lifestyle depends on that. Mobility, heating, industry, logistics….if we want a healthy city we would need to change everything, from design to culture.

Where do we start? No one wants cancer and no one wants to give up a wealthy lifestyle. The consequences however do not just show in economics due to illness, lack of productivity or costs of health care. They also show in quality of life, global problems and huge amount of people with chronic diseases. This mismatch suggests a transformation process. But how do we choose our priorities?

The first project of AiREAS was to create a backbone infrastructure of measurement equipment to visualize our air pollution in the finest detail. One of the most modern requirements is to analyse the ultra fine dust that we create through combustion of fuels or wood and friction. These particles are smaller than a virus and settle in our arteries, creating infections that can give rise to all kinds of health problems, even cancer. Larger particles may be captured by our natural defences, such as nose moisture and small hairs. But the smaller ones go straight through.

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Measuring such minute air particles in the open air in a city is very difficult. Expensive technology so far only reached to a certain point of detail. At AiREAS we managed to cocreate much less expensive equipment that measures a vast amount of variables, and in real time. In Holland we say that “measurement is knowledge”. But what do we know when we measure?

Just imagine this little red dot:


This represents a particle in the free, open air in your city. Now we want to know what it is and how it affects our wellbeing? One way to do this is to filter the air through a membrane. We can then analyse the membrane and whatever it has captured. This did not work for us because we wanted to measure in real time, all the time, without having to go to the measurement station (normally hung up on a light post or so) to change filters or tubes. Another technique is with to measure with light or laser. Air in an air chamber of the measurement station is analysed by the way light is distorted by air particles.

Now we know the quantity of particles per cubic “something” in space somewhere in the city in close to real time. We also know the size. ¬†We can distinguish particulate matter (PM) from below 1 micron to the traditional 2.5 and 10 PM.

This is great and already a huge advantage over other measurement techniques in the world. Scientists helped define the location of the measurement equipment so that information could be interpreted with some degree of reality. But what reality? We are interested in human health. So where can we measure, link with the respiratory reality and health consequences? Why would the measurement at 2.5 meters above a sidewalk under a light post be representative for what happens with people who live in the area? Scientific research talks about modulation. This is a mathematical technique to extrapolate our knowledge at the point of measurement and its validity for interpretation at a certain distance.

Modulation has to do with smart guessing based on behaviour models that take all kinds of variables into account. Every situation is different. Think of the way the wind affects the particles, or rain, gravity, temperature, turbulence around buildings, etc. Should we measure at the light post close to where pollution originates or at home of a local resident where people spend most of the time? Is the health hazard related to what we ingale while on the move or when we are at home? Or is it the accumulation of both. How then does pollution spread? Are our modulation models correct for interpretation? Do we measure at the right places for correct judgement.

These are relevant questions because based on the answers we influence policies on where roads should be changed, how traffic is routed, what needs to be changed in our lifestyle by law or suggestion, etc. These are big responsibilities.

The second backbone we put in place in the city is a health measurement infrastructure with real doctors measuring heart, lung, arteries. By choosing the spots right we could get to see if adjustments in the city or our behaviour would prove to be successful, not just by showing an improvement in air quality but also in related health and quality of life.

Linking public health and air pollution in true real life research with the involvement of the entire city population is quite unique. It is a living lab that teaches us as much as the rest of the world, especially because we do it with all participants at the table, not just fragmented research topics. That is also why we can react instantly on impulses that occur and surprise us. We become aware and conscious as we move.

Recently for instance we had a huge storm, up to hurricane power. This sucked all the polluted air right out of the city. The measurements however did not show uniformity. Strange things happened. The particles did not behave the same way and certainly not the way we would have expected.

Going back to our red dot we realize that we know only the size and quantity of particles. We do not know their weight, mass or properties. So in reality we know very little. These properties behave differently in different circumstances where gravity, climate, weather, electromagnetism, turbulence, etc influence them all the time. How can we interpret air pollution and attach values to it if we have so many doubts? How can we communicate pollution to the public if we don’t even know what kind of pollution we are talking about? How can we take measures in the city if we don’t know how the particles behave before they even get to our lungs and arteries?

We concluded that we need to initiate a new scientific project just to focus on “interpretation” of data.

We decided two things:
1. With two years of citizen’s cooperative work at AiREAS we have accumulated much awareness and experiences to share with others. We will get people to visit us for regular seminars that will allow them to do the same in their home town.

2. We will establish a research team to see how we go about interpretation and communication. We will finance the research through the income from education. Like this we keep ahead of the crowd so to say but let the others in on all our experience building through the trainings.

If of interest please mail. You can also forward this initiative and progress to people in your network who deal with this complex issue.