Background

Titanium dioxide "TiO₂, E171" is a widely used food additive that exists in various everyday food products all over the world together with vast applications in cosmetics and industry. However, many toxicological aspects particularly following oral exposure still unclear.

Methods

Hence, this study was planned to examine the effect of oral exposure of male Wistar rats to two doses of TiO₂ (20 or 40 mg/kg b.wt.) through oral gavage once daily for 90 consecutive days on the blood components, immunity, cytotoxic, and genotoxic indicators.

Results

A dose-dependent leukopenia, eosinophilia, neutrophilia, and thrombocytopenia were noted. Also, the immunoglobins G (IgG) and IgM were significantly elevated in TiO₂ treated rats. The phagocytic activities, lysozyme, nitric oxide, and immunoglobulin levels were significantly depleted following TiO₂ exposure. A significantly reduced lymphocyte proliferation but elevated LDH activity was prominent in TiO₂ treated rats. Different pathological perturbations were observed in both splenic tissue and bone marrow. A marked increase in CD4⁺ and CD8⁺ immunolabeling was evident. A significant increase in the comet variables was recorded in response to the exposure of rats to the increasing level of TiO₂ at both levels.

Conclusion

Overall, these results indicated that TiO₂ could induce hematotoxicity, genotoxic, and immunotoxic alterations with exposure for long durations.

中文翻译：

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长期口服二氧化钛会损害免疫功能并引发大鼠细胞毒性和遗传毒性

背景

二氧化钛“ TiO ₂，E171”是一种广泛使用的食品添加剂，存在于世界各地的各种日常食品中，在化妆品和工业中具有广泛的应用。但是，许多毒理学方面，尤其是口服后仍不清楚。

方法

因此，计划进行这项研究以检查雄性Wistar大鼠口服连续两次连续90天每天两次口服TiO ₂（20或40 mg / kg b.wt.）剂量对血液成分，免疫力的影响，细胞毒性和遗传毒性指标。

结果

注意到剂量依赖性白细胞减少，嗜酸性粒细胞增多，嗜中性粒细胞减少和血小板减少症。同样，在用TiO ₂处理的大鼠中，免疫球蛋白G（IgG）和IgM显着升高。TiO ₂暴露后，吞噬活性，溶菌酶，一氧化氮和免疫球蛋白水平显着降低。在TiO ₂处理的大鼠中，淋巴细胞增殖明显减少，但LDH活性升高。在脾组织和骨髓中均观察到不同的病理学扰动。CD4 ⁺和CD8 ⁺免疫标记明显增加。记录到彗星变量的显着增加是由于大鼠暴露于TiO ₂含量增加而引起的 在两个层次上。

结论

总体而言，这些结果表明，TiO ₂可以长时间暴露而引起血液毒性，遗传毒性和免疫毒性改变。