| Popis: |
In this research, enrichment factor (EF) and pollution load index (PLI) were utilized to explore the contamination characteristics of toxic elements (TEs). The results exhibited that the study area was mainly moderately polluted, and the EF values of Cd, Zn, Pb, Cu and Sb were all > 1, which were cumulative. The concentrations of Cr, Cu, Zn and Pb increased with the decrease of dust particle size. The investigation results of chemical speciation and bioavailability of TEs showed that Zn had the highest bioavailability. Three sources of TEs were determined by positive matrix factorization (PMF), Pearson correlation analysis and geostatistical analyst, comprising factor 1 mixed sources of industrial and transportation activities (46.62%), factor 2 natural source (25.56%) and factor 3 mixed source of agricultural activities and the aging of park infrastructures (27.82%). Potential ecological risk (PER) and human health risk (HHR) based on PMF model were exploited to estimate PER and HHR of TEs from different sources. The PER value of TE in the park dust was 114, indicating that ecological risk in the study area was relatively high. Factor 1 contributed the most to PER, and the pollution of Cd was the most serious. There were no significant carcinogenic and non-carcinogenic risks for children and adults in the study area. And factor 3 was the biggest source of non-carcinogenic risk, As, Cr and Pb were the chief contributor to non-carcinogenic risk. The primary source of carcinogenic risk was factor 2, Cr was the cardinal cancer risk element. |
