Abstract:There is no universally accepted approach for evaluating lead (Pb) bioavailability in soil. The diffusive gradient in thinfilms (DGT) technique is a promising tool which has been used for evaluating the bioavailability of heavy metals in water and sediment. The principle of DGT is based on Fick’s first law of diffusion. The ability of this technique to estimate Pb bioavailability in soils was compared with the abilities of other traditional chemical extraction techniques (soil solution, ethylene diamine tetraacetic acid (EDTA), acetic acid (HAc), calcium chloride (CaCl2), and pseudototal Pb methods) based on a greenhouse experiment using Brassica chinensis grown in 15 soils from different provinces of China. In addition, whether these methods were independent of soil properties were assessed. Correlations between the plant and soil Pb concentrations measured with the traditional extraction techniques were dependent on the pH value and organic carbon (OC) content, indicating that these methods were influenced by the soil properties. The regression coefficients (R2) were increased when these prediction models, including soil properties (pH value and OC) though the stepwise multiple linear regressions compared with simple linear regressions besides DGT method. In contrast, the DGT measurements were independent of the soil properties and showed a higher correlation coefficient compared with that of the traditional techniques. And the prediction model built by DGT (R2=0.97, p<0.01) showed a highest R2. Hence, the DGT technique was better and should be preferable for assessing Pb biological effectiveness in different soil types.