Question

What poisonous gas is found in the exhaust fumes of car engines?

Answer 1

Hi Mayliz - The combustion of fuels (oil, gas, coal, etc) produces a number of different chemicals. Some are considered harmless, such as carbon dioxide, because they occur naturally, however carbon dioxide is a "greenhouse gas" that, in large quantities, contributes to global warming. Because of the high number of cars on the road, plus industrial emissions, there is an overabundance of this "harmless" gas in the environment, which is a problem.

However, combustion also results in smaller quantities of some toxic gases, like carbon monoxide. You might have heard stories about someone running their car without opening the garage door who ultimately died of carbon monoxide poisoning. This is because the small quantity builds up in a confined space and overburdens the immune system.

Here is a website from the BBC where you can read about some of the health effects associated with exhaust emissions, including those produced by car engines. I hope this helps: http://www.bbc.co.uk/health/physical_health/conditions/exhaust_emissions.shtml

Answer 2

Atam is right about all except the mechanism by which carbon monoxide poisoning affects you.

The gas molecules themselves have no effect on your immune system (although prolonged, low level or repeated periodic exposure may have indirect effects on it). Instead, the CO molecules bind to hemoglobin with higher affinity than oxygen. These CO molecules sequester the hemoglobin molecules available for oxygen transport, so it essentially suffocates you at the molecular level. Best wishes,

Answer 3

Thanks Atam and Blues

Answer 4

Blues is right - I simplified my answer because the original question was about the gases themselves. The pathway Blues mentioned is more accurate. The same thing can be said about mercury. People think that swallowing mercury (such as in a thermometer) is deadly, but most of the physical substance is actually excreted from the body. It is mercury vapor that is truly toxic. Well said, Blues!

Answer 5

I know, but I thank you for the effort and information