2de55cd4_ealth_Effects_of_Air_Pollution__Sources
[Air Pollutant] Lead [Health Effects] Lead is a highly toxic and is known to damage the nervous system and kidney, and interfere with the synthesis of haemoglobin. Children are more vulnerable to the effects of lead, which can result in learning disabilities and impaired neurobehavioural functioning. [Sources] 
Lead occurs naturally in the earth's crust but the natural sources contribute only a small fraction of the amount of lead found in air, food, water and dust. The majority of lead in these media arises from automobile and industrial emissions and from the use of lead-containing solder and paints. The lead content in vehicular exhaust is the result of using organolead compound as fuel additives. However, a ban on the use of leaded petrol in Hong Kong in 1999 has completely eliminated the emissions of lead from motor vehicles.
Centre for Health Protection - The Health Effects of Air Pollution
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