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Lead species significantly influences its mobility and bioavailability. In this study, improved BCR procedure, laboratory culture, laboratory micro X-ray fluorescence (μ-XRF), and synchrotron radiation X-ray absorption near-edge structure (XANES) were used to investigate the distribution, speciation, and bioavailability of Pb in soils from a Pb/zinc (Zn) mining area contaminated with heavy metals. The results showed that ① Pb was mainly distributed in the reducible[which binds to oxides of iron (Fe) and manganese (Mn)], acid soluble, residual, and oxidizable fractions, ② Pb content in plant tissues correlated with acid-soluble Pb content in soil, ③ μ-XRF results indicated that Pb was distributed heterogeneously, and correlated with the hot spot with high concentration of Mn. In some area, Pb also correlated with Fe, and ④ Pb was predominantly present as Pb-goethite (41%-46%), Pb 3 (PO 4 ) 2 (36%-55%), and Pb-MnO 2 (3%-24%) in soil samples. The results of this study showed that oxides of Fe and Mn, and Pb 3 (PO 4 ) 2 precipitate mainly comprise the pool of Pb in soils.

Qixiashan lead-zinc mine of Nanjing was one of the largest lead zinc deposits in East China Its exploitation has been over 50 years, and the environmental pollution has also been increasing. The lead concentration in the local environment was high, but lead migration and toxic mechanism has not been clear. Therefore, biogeochemistry research of the lead zinc mine was carried out. Using ICP-MS and Pb-L III edge XANES, lead concentration and speciation were analyzed respectively, and duckweed which can tolerate and enriched heavy metals was found in the pollution area. The results showed that the lead concentration of duckweed was 39.4 mg x kg(-1). XANES analysis and linear combination fit indicated that lead stearate and lead sulfide accounted for 65% and 36.9% respectively in the lead speciation of duckweed, suggesting that the main lead speciation of duckweed was sulfur-containing lead-organic acid.

The data of in vivo XRF Pb in human bone were obtained within China by using the in vivo XRF set. The K series X-ray of Pb were applied to determine the in vivo Pb concentration in tibia and calcaneus among Chinese mainland residents. For general population, the weighted average of Pb in bone was 0.4-22.7 microg x (lead g bone mineral)(-1). The uncertainty was 7.0-12.5 microg x (lead g bone mineral)(-1), and the average minimun detection limit was 20.3 microg x (lead g bone mineral)(-1). For residents from pollution area, the maximum Pb in bone reached up to 73.9 microg x (lead g bone mineral)(-1).