what are the impacts on health by sulphur dioxide, nitrogen oxide, carbon monoxide and lead.

Sulphur dioxide: chest infections, irritation of lungs, asthma etc.
Carbon mono oxide: Affects the transportation of oxygen in our body. If the level gets very high it affects the oxygen supply. Also causes nausea fatigue and dizziness.
Lead: Neurotoxic, harmful for brain, kidney and reproductive function in our body.