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Changing properties of atmospheric lead pollution in Beijing |
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Abstract Aerosol lead data during 1985~2009 were thoroughly analyzed with aim to reveal the changing properties of the atmospheric lead pollution in Beijing. There was a 10a quasi-cycle variation in the changes of the aerosol lead concentration in Beijing. The aerosol lead concentration at Chegongzhuang station was in upward/downward tendency per approximately 10 a. Greatly influenced by steel melting, the aerosol lead concentration at Gucheng station increased quickly but decreased slowly during 1990’s. Under the impacts of the increased regional air pollution emissions, the background aerosol lead concentration in recent 20 years was dominated by increase in Beijing, and the difference of lead concentration between background and city was greatly reduced. The phase-out of leaded gasoline in the late 1990’s decreased the aerosol lead level significantly, but its effect was counteracted by the strong increase of other lead sources. Later air cleaning measures taken during 2008 Beijing Olympic Games reduced lead emissions, however lead’s ratio to other heavy metal was rising. The lead concentrations remained low after, possibly derived from Olympic source control efforts, a down turn in the economy and the adjustment of industrial structure.
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Received: 30 November 2009
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