Titanium dioxide nanoparticles may damage male fertility |二氧化钛纳米颗粒可能会损害男性的生育能力

A new study in the Journal of Hazardous Substances shows that titanium dioxide-an artificial nanomaterial commonly used in processed foods, dietary supplements, food ingredients and cosmetics, can cause testicular damage and affect the male reproductive system.

Inhaled nanoparticles have been regarded as human carcinogens by the World Health Organization. Recent studies have shown that ingested nanoparticles can accumulate in the liver, kidneys and brain, damage DNA and cause genetic mutagenesis and potential carcinogenesis.

G in Suzhou University School of Medicine, Suzhou City. Research by Dr. Gao and his colleagues found that the ingested titanium dioxide may spread to male testes, accumulating testicular damage, sperm abnormalities and changes in plasma sex hormone levels.

For this study, male mice were fed 2.5, 5, and 10 mg/kg body weight of titanium dioxide nanoparticles daily for 90 days, and then gene expression was measured to see how these nanoparticles affect genes in the testes.

The researchers found that titanium dioxide nanoparticles up-regulated 70 genes with known functions, and down-regulated 72 genes in the testis exposed to titanium dioxide nanoparticles. Of the affected genes, six are involved in spermatogenesis, and the other six are related to steroid and hormone metabolism. Shows that titanium dioxide nanoparticles can affect sperm production, steroids and hormone metabolism.

The author warns that “the production and application of titanium dioxide nanoparticles should be carried out with caution, especially for people of reproductive age”.

This is not the first study to show that exposure to titanium dioxide nanoparticles may damage the male reproductive system. The early research report “Toxicology and Industrial Health” released in October 2012 has found that nanoparticles, especially titanium dioxide, can affect male fertility.

K. Pawar and G. Kaul of the Kanal National Dairy Research Institute in Haryana, India, conducted a laboratory study and found that exposure to titanium dioxide negatively affects sperm function and enhanced DNA division.

Nanoparticles can enter cells and cause DNA breaks, mutations and even carcinogenesis. Since the damage is caused by the physical properties of nanoparticles, other nanoparticles such as zinc oxide and silica are also commonly used in processed foods and dietary supplements, and may cause the same health hazards. Nanoparticles are naturally occurring. Therefore, the industry believes that the synthesized nanoparticles should be safe.

In many foods and food ingredients, titanium dioxide and other nanoparticles can be used in doses up to 2%. Nano particles are generally used to whiten or help powder dispersion. But they are also commonly used for other purposes. For example, zinc oxide is used as a zinc fortifier in food and health products. (David Liu)

危害物质杂志的一项新研究表明，二氧化钛 – 一种常用于加工食品，膳食补充剂，食品成分和化妆品的人造纳米材料，可能导致睾丸损伤并影响男性生殖系统。

吸入的纳米颗粒已经被世界卫生组织视为人类致癌物质。最近的研究表明，摄入的纳米颗粒可以积累在肝脏，肾脏和大脑中破坏DNA并引起基因诱变和潜在的致癌作用。

在苏州市苏州大学医学院Ｇ。高博士和同事的研究发现，摄入后的二氧化钛可能会传播到男性睾丸，累积睾丸损伤，精子畸形和血浆性激素水平的变化。

为该研究，雄性小鼠每天喂养2.5,5和10mg / kg体重的二氧化钛纳米颗粒90天，然后测定基因表达以观察这些纳米颗粒如何影响睾丸中的基因。

研究人员发现二氧化钛纳米粒子上调70个具有已知功能的基因，并在二氧化钛纳米颗粒暴露睾丸中下调了72个。在受影响的基因中，六个参与精子发生，另外六个与类固醇和激素代谢相关。表明，二氧化钛纳米粒子可以影响精子产生，类固醇和激素代谢。

作者警告说，“二氧化钛纳米粒子的生产和应用应该谨慎进行，特别是生殖年龄人”。

这不是第一个研究表明暴露于二氧化钛纳米颗粒可能会损害男性的生殖系统。 2012年10月发布的早期研究报告“毒理学与工业健康”已经发现，纳米粒子特别是二氧化钛可以影响男性的生育能力。

印度哈里亚那州卡纳尔国家乳品研究所的K. Pawar和G. Kaul进行了实验室研究，发现暴露于二氧化钛负面影响的精子功能和增强的DNA分裂。

纳米颗粒可以进入细胞并导致DNA断裂，突变甚至致癌作用。由于损伤是由纳米粒子的物理性质引起的，其他纳米颗粒如氧化锌和二氧化硅也是加工食品和膳食补充剂中常用的，可能会造成相同的健康危害。纳米颗粒有天然存在的。因此，工业界认为合成的纳米颗粒应该是安全的。

在许多食品和食品成分中，二氧化钛和其他纳米颗粒可以以高达2％的剂量使用。纳米颗粒一般用来增白或帮助粉末分散。但它们也常用来于其它目的。比如，氧化锌在食品和保健品中用作锌的强化剂。（刘大卫）