Department of Biological and Environmental Sciences, University of Messina , Viale F. Stagno d'Alcontres 31, S. Agata - 98166, Messina , Italy.
Nanotoxicology. 2014 Aug;8(5):549-58. doi: 10.3109/17435390.2013.807446. Epub 2013 Jun 13.
Marine bivalves (Mytilus galloprovincialis) were exposed to titanium dioxide (10 mg L(-1)) either as engineered nanoparticles (nTiO2; fresh, or aged under simulated sunlight for 7 days) or the bulk equivalent. Inductively coupled plasma-optical emission spectrometry analyses of mussel tissues showed higher Ti accumulation (>10-fold) in the digestive gland compared to gills. Nano-sized TiO2 showed greater accumulation than bulk, irrespective of ageing, particularly in digestive gland (>sixfold higher). Despite this, transcriptional expression of metallothionein genes, histology and histochemical analysis suggested that the bulk material was more toxic. Haemocytes showed significantly enhanced DNA damage, determined by the modified comet assay, for all treatments compared to the control, but no significant differences between the treatments. Our integrated study suggests that for this ecologically relevant organism photocatalytic ageing of nTiO2 does not significantly alter toxicity, and that bulk TiO2 may be less ecotoxicologically inert than previously assumed.
海洋双壳贝类（贻贝）暴露于二氧化钛（10mg/L），无论是作为工程纳米颗粒（nTiO2；新鲜的，或在模拟阳光下老化 7 天）还是体相等效物。对贻贝组织的电感耦合等离子体-光学发射光谱分析显示，与鳃相比，在消化腺中钛的积累更高（>10 倍）。无论老化与否，纳米级 TiO2 的积累都大于体相，特别是在消化腺中（>六倍）。尽管如此，金属硫蛋白基因的转录表达、组织学和组织化学分析表明，体相材料更具毒性。与对照组相比，所有处理组的血细胞的 DNA 损伤都明显增强，用改良的彗星试验测定，但处理组之间没有显著差异。我们的综合研究表明，对于这种具有生态相关性的生物，nTiO2 的光催化老化并没有显著改变其毒性，并且与之前的假设相比，体相 TiO2 可能没有那么惰性。
