GUANGZHOU - Emissions from local businesses and natural environment in a township of South China's Guangdong province have led to lead poisoning, a spokesman with the local county government said at a press conference Saturday.

According to the preliminary investigation, children's suffering from lead poisoning in Dongtang township of Renhua county, resulted mainly from having been inhaling lead-contaminated air and eating lead-contaminated food. Emissions by local businesses and soils with high lead contents in the area were blamed for the contamination.

Of the 531 residents in Dongtang who have had their blood tested as of Feb. 29, 160 children have been diagnosed with elevated blood lead levels, according to local health department.

Experts investigated factories and mining zones, and analyzed air, water, soil and farm produce around the town.

Research findings showed that Dongtang township was located in a large-scale lead-zinc ore belt, so the level of lead in the soils is much higher than other neighboring regions.

Waste gas containing lead, which was discharged by some local factories, is also a main cause for the children lead poisoning.