Lead

Particulate matter

Carbon monoxide

Sulphur dioxide

Affects circulatory, reproductive, nervous and renal systems; suspected of lowering learning ability in children; hazardous even after exposure ends.

 Fine particles may cause lung cancer; a strong correlation exists between suspended particulates and infant mortality in urban areas.

 Affects fetal growth in pregnant women and tissue development of young children; impairs perception and thinking, slows reflexes and causes drowsiness; can cause unconsciousness and death.

 Exacerbates asthma, bronchitis and emphysema; causes coughing and impairs lung functions.