Can we model our exposure to our environment? Understanding human health has always been important to society – as, naturally, we do not particularly like it when we know someone who is ill. Current research has asked questions such as: What are the genetic predispositions to the illness?; How long have these illness been present and when did exposure to it occur?; and Where is this occurring?
The traditional approach to epidemiology (the study of the distribution and determinants of illnesses) has been based on the fact that people are fairly static in their lives. Yet more people are moving all the time, not just in the same area but moving regions and nations as well. Another factor is that we don’t estimate exposure by tracking individuals in their daily lives.
This is where the exposome (the area in which we are exposed to illnesses) comes into the discussion. Two thirds of deaths are caused by non-communicle (non infectious) illnesses and only ten percent are due to genetic variations. Therefore the rest are caused by our environment. The idea of looking at how life circumstances affect human health is not a new one; John Wallis in 1790 describes an idea of following people from birth until death and to measure their health throughout. The exposome assess three aspects of life: the internal aspects; the general external situations (such as social stressors); and the specific external factors which include radiation and lifestyle factors.
Professor Clive Sabel has been researching the routines of daily lives and the risk of exposure to such illnesses. In our everyday lives we will come across various hazards – whether this is crossing the road, walking into secondary smoke, or even eating something amazingly unhealthy. By mapping these movements through the course of the day, we can begin to see some very interesting patterns.
How can we track people in their everyday lives? We can use government data to help such as census data and schools in England often send out questionnaires to students’ families asking how they get to school. We can also use social media – such as Tweeting where you are and now on Facebook you can ‘Check in’ with a status update.
Technology has made things a bit easier. There are all kind of fitness measuring devices that also come with GPS (Global Positioning System) to help route plotting and future setting. Most people have a smart phone. Most smart phones have a GPS built into them. A lot of apps ask for location data: coincidence?
Clive Sabel’s pilot study is to investigate how location and activity to assess risks to health in relation to being indoors or outdoors. To do this they were given a range of equipment which measured location, ultraviolet radiation, temperature, and they wrote a paper log of what they did. They did this across seven cities in Europe: Edinburgh, Zeist, Stuttgard, Zagreb, Thessaloniki, Kozani and Athens. Each individual collected data for seven days and carried the equipment wherever they went.
Ultimately, with enough information, it may be possible to create an agent based model to simulate behaviour between daily lives and exposure to containments. This, in time, will help those in the medical profession to model illness and use the environmental/spatial aspects of illnesses and to find ways to treat them.
(MSc in GIS at the University of Edinburgh)