[Analysis of Heavy Metal Pollution Evaluation and Correlation of Farmland Soil and Vegetables in Zhaotong City].

A farmland area in Zhaotong City was taken as the research object， and the method of point-to-point collaborative sampling was used to collect farmland soil and vegetables in Zhaotong and test the content of six heavy metals， namely As， Pb， Cu， Zn， Cd， and Cr. The geo-accumulation index and potential ecological risk index were used to evaluate the heavy metal pollution of soil. The health risk model was used to evaluate the risk to the human body imposed by vegetables. The results showed that Cu， Zn， Pb， Cd， and Cr pollution existed in the research area. Compared with the risk screening value of farmland， the over-standard rates were 34.35%， 6.87%， 2.29%， 80.15%， and 6.11%， respectively； Pb， Cd， and Cr were found in vegetables. Compared with the pollutant limit in food， the over-standard rates were 6.87%， 15.27%， and 36.64%， respectively. According to the soil pollution evaluation， Cd in the soil showed a strong ecological risk， and other heavy metals in the soil showed a mild ecological risk. The human health risk evaluation model showed that both non-carcinogenic risk and carcinogenic risk were out of the acceptable range and had a greater influence on children. Correlation analysis showed that As in the soil had an antagonistic effect on Cu and Zn absorption by vegetables， whereas Cr in the soil could promote Cu and Zn absorption by vegetables.

Quantitative Source Apportionment of Potentially Toxic Elements in Baoshan Soils Employing Combined Receptor Models.

Arable soils are crucial for national development and food security; therefore, contamination of agricultural soils from potentially toxic elements (PTEs) is a global concern. In this study, we collected 152 soil samples for evaluation. Considering the contamination factors and using the cumulative index and geostatistical methods, we investigated the contamination levels of PTEs in Baoshan City, China. Using principal component analysis, absolute principal component score-multivariate linear regression, positive matrix factorization, and UNMIX, we analyzed the sources and quantitatively estimated their contributions. The average Cd, As, Pb, Cu, and Zn concentrations were 0.28, 31.42, 47.59, 100.46, and 12.36 mg/kg, respectively. The Cd, Cu, and Zn concentrations exceeded the corresponding background values for Yunnan Province. The combined receptor models showed that natural and agricultural sources contributed primarily to Cd and Cu and As and Pb inputs, accounting for 35.23 and 7.67% pollution, respectively. Industrial and traffic sources contributed primarily to Pb and Zn inputs (47.12%). Anthropogenic activities and natural causes accounted for 64.76 and 35.23% of soil pollution, respectively. Industrial and traffic sources contributed 47.12% to pollution from anthropogenic activities. Accordingly, the control of industrial PTE pollution emissions should be strengthened, and awareness should be raised to protect arable land around roads.