Abstract:
This paper is the result of environmental geological survey engineering.
Objective To investigate the contamination characteristics, sources, and ecological risk status of potentially toxic elements (PTEs) in soils around urban fringe areas.
Methods Soil samples were collected from 456 surface layers (0-20 cm) around the fringe area of Tengzhou City, and As, Cd, Cr, Cu, Hg, Ni, Pb and Zn contents were determined. The geo-accumulation index method and potential ecological risk index method were used to assess the pollution characteristics of urban PTEs, the Absolute Principal Component Score-Multiple Linear Regression (APCS-MLR) model and Positive Matrix Factorization (PMF) were used to quantitatively resolve the sources of PTEs pollutants, and the health risk index model was used to assess the risk to human health.
Results The ecological risk of surface topsoil is relatively low, Hg pollution is the most serious, and Hg pollution is characterized by large spatial variations, aggregation of pollution, and serious influence by human activities. Source analysis showed that soil PTEs in the edge area of Tengzhou originated from natural, industrial, transportation and agricultural sources, which accounted for 39.59%, 29.48%, 25.17% and 5.77% in the APCS-MLR model, and 29.64%, 15.38%, 28.03% and 26.93% in the PMF model. The human health risk evaluation showed that non-carcinogenic risk for adults was low, the non-carcinogenic risk for children and the total carcinogenic risk for population were high, and As and Cr had some carcinogenic hazards.
Conclusions The main source of surface soil PTEs is the geological background, and attention should be paid to Hg, As and Cr monitoring and treatment. It is recommended that the monitoring of drinking water resources be strengthened, and that traffic pollution emissions be reduced and the regulation of factory waste emissions be strengthened.
下载: