Home Resources Links FAQs Commentaries Search Help
 
Home Page for Health, Environment and Work Click on Image

Learning about Air Quality: 2 (Today)


Introduction:

This self-learning tutorial is intended to help you learn about the determinants of air quality, using UK examples of actual air quality data, and to give some guidance as to the understanding of these data. It is the second of three parts: 
  You will need to put a 'bookmark' on this site, i.e. place it in your 'hotlist', and come back to it from time to time, to gain the full benefit of it. You should try coming back at different times of the year (bleak midwinter, fine summer, and at different times of day e.g. before the morning rush hour, and after the evening rush hour if you live in a city, and are following the air quality in a city).
 

2. Learning from the Present

To learn from this part of the exercise, you will need to take today's Air Quality as an example and learn from it, probably by coming back to this site at intervals. If you are in Edinburgh or in another British location close to an automatic monitoring site, it will be easy. Otherwise you will need to work out for yourself which urban (or rural) monitoring site is likeliest to mirror your location in its air quality experience. 

Now, how about finding out what the air quality, (in terms of the concentrations of the major air pollutants) has been in the last hour or so. You could click on the coloured links below to find out, but you will learn more if you exercise your thoughts before you do so, by considering some simple questions: 

Is today an average day without cause for a substantial increase in pollution emissions in the area concerned, and there is at least a moderate breeze? 

If so, the pollutant concentrations are not likely to be high, and the air quality will probably be labelled as low. However, if as you read this page, you are in a city, there is heavy traffic on the streets, it is a cold wintry day, but not windy, then some pollutant concentrations might be elevated i.e. the air quality would be at least 'moderate'. Having made your 'guesstimate', look at the real data for the following pollutants as measured throughout the UK in the last hour or two: 

The above substances may be important gaseous pollutants. Thus, in high enough concentrations, nitrogen dioxide might harm the lungs, carbon monoxide can reduce the capacity of delivering oxygen to the heart and to other tissues, while benzene, and 1,3 butadiene may be associated with an increased cancer risk. However, most of the time the levels are in the 'very good' band and as such are not associated with a known risk to human health. 

In some special circumstances, as in the past example number 2 which was based in Belfast where sulphur containing solid fuel is still burnt in significant quantities, especially in winter, Sulphur Dioxide <remember to close the window after use>pollution may still be worth considering. Asthmatics may experience a worsening of their symptoms when sulphur dioxide concentrations rise. 

If it is a bright sunny day, and has been so for a few hours then concentrations of the secondary pollutant Ozone  <remember to close the window after use> may begin to rise. Especially in the rural areas, in the South of England, this is one to watch out for in summer on fine days. It can also be a problem in cities, but this is less likely since nitric oxide from car exhausts tends destroys ozone. Asthmatics may experience a worsening of their symptoms when ozone concentrations rise. 

All the above pollutants are distinct, relatively simple chemical entities. One very important pollutant regularly monitored by the network throughout the country is Particulate Matter (PM10) <remember to close the window after use>. It is not simple in its composition, causes, or health effects, and may be elevated on occasions, either in winter or in summer (although for different reasons). High concentrations of fine particulate matter are associated with an increased health risk to the lungs, and to the cardiovascular system (heart and blood vessels).

 

Other questions...

Some of your questions may have been answered, but probably not all. What exactly is 'very good' in terms of air quality, especially when a mixture of pollutants is concerned? Is it good enough?... for most people?... for everybody? 

Work is in progress to adapt teaching material that answers these questions, or to provide links to other sites which do. 

 

Acknowledgements etc