Benzene (C 6 H 6 )
What is it? Benzene is an aromatic hydrocarbon which is liquid, inflammable and has no colour. It is also used as antiknock in unleaded petrol. Human activities produce benzene, especially with oil, mineral oil and its derivates manipulation, which can pollute the air. Most danger for people comes from car exhaust gas, particularly from petrol powered vehicles: EU statistics quote the pollution produced by this category of vehicles to be the 70% of the total quantity of benzene in the air.
Damage caused- Studies show that Benzene can cause cancer to human beings. Serious damages to the bone marrow are caused by contact to high-concentration of benzene. A chronic exposure can cause leukaemia - this has been found in factory workers as well as rubber and oil industry workers. WHO statistics state that four per million people are put through the risk of leukaemia because of an exposure of 1g/m 3 of benzene during the whole life.
Development- The amount of benzene in the latest years is falling, due to the introduction of a 1% limit in the tenor of benzene in petrol, introduced in the month of July 1998, as well as for the increasing number of catalyzed engines in cars.
Range of allowed values, according to law (DM n. 60 del 02/02/2002)
|
Max concentration per year ( µ g/mc) |
|
Max quantity for human health |
5 |
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Tolerance limit |
+ 5 in 2006 decreasing 1 unit every year |
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Range of values in urban centres
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Limit for human health per year ( µ g/mc) |
|
Low limit |
0.25 |
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High limit |
0.35 |
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