The Lead Chemical Speciation Analysis and Bioavailability Assessment about Main Locality Soils of Chinese Prickly Ash in Sichuan

In this study,we took 18 experimental points' soils from Chinese prickly ash main production areas in Sichuan as research objects to evaluate the total lead pollution with Nemerow Index Method,analyzed 5 forms of lead in each sample,compared the lead bioavailability and mobility of samples in main production areas,and studied the effect of pH value on lead chemical forms and bioavailability.The results showed that the residual lead contents in locality soils were significantly higher than those of other 4 forms; the lead contents of Fe/Mn oxide were significantly higher than those of organic forms,carbonate forms,and exchangeable forms; the soil samples' bioavailability and mobility were much lower than others when pH>7; the bioavailability and mobility of soil samples in main production area B were much higher than those in area A and other areas.According to the current limit standard for Sichuan forest food production environment and product,the total lead contents in locality soils of Chinese prickly ash had certain overproof risk which needed timely monitoring.However,the locality soils' lead pollution reflected by the limit standard and Nemerow assessment result was a little one-sided,so we recommended adding the determination of available lead contents to serve as auxiliary analysis.