Fang Jing, Shan Xiao-quan, Wen Bei, Lin Jin-ming, Owens Gary
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
Environ Pollut. 2009 Apr;157(4):1101-9. doi: 10.1016/j.envpol.2008.11.006. Epub 2008 Dec 10.
The stability of TiO(2) nanoparticles in soil suspensions and their transport behavior through saturated homogeneous soil columns were studied. The results showed that TiO(2) could remain suspended in soil suspensions even after settling for 10 days. The suspended TiO(2) contents in soil suspensions after 24h were positively correlated with the dissolved organic carbon and clay content of the soils, but were negatively correlated with ionic strength, pH and zeta potential. In soils containing soil particles of relatively large diameters and lower solution ionic strengths, a significant portion of the TiO(2) (18.8-83.0%) readily passed through the soils columns, while TiO(2) was significantly retained by soils with higher clay contents and salinity. TiO(2) aggregate sizes in the column outflow significantly increased after passing through the soil columns. The estimated transport distances of TiO(2) in some soils ranged from 41.3 to 370 cm, indicating potential environmental risk of TiO(2) nanoparticles to deep soil layers.
研究了二氧化钛纳米颗粒在土壤悬浮液中的稳定性及其通过饱和均质土柱的迁移行为。结果表明，即使沉降10天后，二氧化钛仍能悬浮在土壤悬浮液中。24小时后土壤悬浮液中悬浮的二氧化钛含量与土壤中的溶解有机碳和粘土含量呈正相关，但与离子强度、pH值和zeta电位呈负相关。在含有相对大直径土壤颗粒和较低溶液离子强度的土壤中，相当一部分二氧化钛（18.8 - 83.0%）很容易通过土柱，而二氧化钛在粘土含量较高和盐度较高的土壤中被显著截留。通过土柱后，柱流出物中二氧化钛聚集体尺寸显著增加。在某些土壤中，二氧化钛的估计迁移距离为41.3至370厘米，表明二氧化钛纳米颗粒对深层土壤层存在潜在环境风险。
