Isotopic signatures and source apportionment of Pb in ambient PM2.5

Chien-Cheng Jung,Chih-Wei Chang,Charles C.-K Chou,Wei-Chen Kuo,Yi-Tang Huang,Shih-Yu Chang,Chung-Te Lee,Chuan-Yao Lin,Hing-Cho Cheung,Shuenn-Chin Chang

doi:10.1038/s41598-022-08096-1

Abstract

Particulate lead (Pb) is a primary air pollutant that affects society because of its health impacts. This study investigates the source sectors of Pb associated with ambient fine particulate matter (PM2.5) over central-western Taiwan (CWT) with new constraints on the Pb-isotopic composition. We demonstrate that the contribution of coal-fired facilities is overwhelming, which is estimated to reach 35 ± 16% in the summertime and is enhanced to 57 ± 24% during the winter monsoon seasons. Moreover, fossil-fuel vehicles remain a major source of atmospheric Pb, which accounts for 12 ± 5%, despite the current absence of a leaded gasoline supply. Significant seasonal and geographical variations in the Pb-isotopic composition are revealed, which suggest that the impact of East Asian (EA) pollution outflows is important in north CWT and drastically declines toward the south. We estimate the average contribution of EA outflows as accounting for 35 ± 15% (3.6 ± 1.5 ng/m3) of the atmospheric Pb loading in CWT during the winter monsoon seasons.

Highlights

Scientific studies have demonstrated that exposure to lead (Pb) particles is associated with hypertension[1,2]
We present an in-depth analysis on two datasets, which were produced by the Taiwan Environmental Protection Administration (EPA) PM2.5 speciation program in 2017–2019 and an intensive investigation conducted in the central-western Taiwan (CWT) from 2016 to 2018, respectively
The results in this study indicate that the ambient concentration and mass mixing ratio of Pb in PM2.5 over CWT were significantly higher during the East Asian (EA) winter monsoon seasons than those during the summertime

Summary

Introduction

Scientific studies have demonstrated that exposure to lead (Pb) particles is associated with hypertension[1,2]. Analysis of the geographical distribution of the Pb isotope ratios (i.e., 206Pb/207Pb and 208Pb/207Pb) of P M2.5 samples is conducted to investigate the influences of air pollution originating from local sources and/or transported by EA continental outflows during the winter monsoon seasons.

Results

Conclusion