Carbon Monoxide (CO)
What is it? It's the gas pollutant released in the highest quantity in atmosphere. It has no smell and no colour, and it is produced by combustion of organic materials. Vehicular traffic is the main source (about 80%), particularly from exhausts of petrol powered vehicles. Higher concentration of CO is found in typical intense urban traffic, low speed and queuing at traffic lights.
Damage caused- CO affects haemoglobin in blood, preventing from regular oxygen transportation to all parts of the body. It affects the nervous system and the cardio-circulatory system, especially in people suffering from heart problems. Very high concentration of CO may cause death by asphyxia; noxious effects of CO are bigger for tobacco smokers.
Development- In the latest 20 years concentration of CO has been consistently reduced thanks to the new technologies for vehicle engines: the catalytic exhaust pipes. At present only 50% of cars use them, but the situation will improve as soon as all vehicles use catalytic exhaust.
Range of allowed values, according to law (DM n. 60 del 02/02/2002)
|
Max concentration 8 hours ( µ g/mc) |
Max quantity for human health |
10 |
Tolerance limit |
none |
Range of values in urban centres
|
Human health (year) ( µ g/mc) |
Low limit |
5 |
High limit |
7 |
|