Metals and possible sources of lead in aerosols at the Dinghushan nature reserve, southern China.

Rapid communications in mass spectrometry : RCM

PubMedID: 26147480

Zhu XM, Kuang YW, Li J, Schroll R, Wen DZ. Metals and possible sources of lead in aerosols at the Dinghushan nature reserve, southern China. Rapid Commun Mass Spectrom. 2015;29(15):1403-10.
RATIONALE
Aerosols play an important role in depositing metals into forest ecosystems. Better understanding of forest aerosols with regard to their metal content and their possible sources is of great significance for air quality and forest health.

METHODS
Particulate matter with an aerodynamic diameter less than 2.5?µm (PM2.5 ) in aerosols was collected every month for 20?months using moderate-volume samplers in the Dinghushan (DHS) nature reserve in southern China. The concentrations of metals (Al, Cd, Mn, Ni, Pb, and Zn) as well as the Pb isotopic ratios in the PM2.5 samples were measured by inductively coupled plasma mass spectrometry (ICP-MS).

RESULTS
Moderate pollution with aerosol PM2.5 was detected at the DHS nature reserve with the air mass from mainland China being the predominant PM2.5 source. The high enrichment factors (EFs) for the heavy metals Pb, Cd, and Zn, as well as the PM2.5 mass concentrations, coupled with backward trajectory analysis, indicated the anthropogenic origins of the PM2.5 and of the heavy metals in the PM2.5 . The Pb isotopic ratios revealed the contributions from various Pb sources, which varied between seasons.

CONCLUSIONS
Industrial emissions and automobile exhaust from the Pearl River Delta (PRD) primarily contributed to the anthropogenic Pb in PM2.5 , although there was occasionally a contribution from coal combustion during the wet season. Pb isotopic ratios analyses are helpful for air quality assessment and Pb source tracing. Copyright © 2015 John Wiley & Sons, Ltd.