Department of Chemistry, Sapienza University, P.le Aldo Moro 5, 00185 Rome, Italy.
Department of Technological Innovations and Safety of Plants, INAIL, Products and Anthropic Settlements, Via di Fontana Candida 1, Monte Porzio Catone, 00078 Rome, Italy.
Int J Environ Res Public Health. 2020 Dec 5;17(23):9085. doi: 10.3390/ijerph17239085.
Titanium dioxide is produced or imported into the EU for over one million tons/year. The International Agency for Research on Cancer (IARC) classification is 2B, a possible inhalation carcinogen for humans. This study evaluates urinary biomarkers of oxidative stress in workers of a plant producing TiO pigment powder, having 0.25 µm average particle size and an ultrafine fraction, compared to unexposed subjects. Urine samples were collected from forty workers before and after the shift, from six employees of the same company and eighteen volunteers from the same geographical area. Titanium and other metals concentrations were measured by ICP-MS, while DNA, RNA, and protein oxidation products by HPLC/MS-MS. A statistically significant increase was found for the urinary concentration of Al, Cd, Cr, Cu, Fe, Mn, Pb, Ti, and Zr, and for all biomarkers of oxidative stress in post-shift workers' urine samples. Urinary concentrations after the working shift were higher than for employees and volunteers pooled together for Cd, Mn, and Zr, and for the oxidative stress biomarkers 8-oxoGuo, 8-oxodGuo, and 3NOTyr. Biomonitoring studies on dose and effect biomarkers for TiO occupational exposure provide information useful for protecting workers' health even in conditions that comply with health and safety standards, highlighting reversible effects of chronic exposure at very low doses.
二氧化钛的年产量或进口量超过一百万吨/年。国际癌症研究机构（IARC）将其归为 2B 类，即可能对人类具有吸入致癌性。本研究评估了生产 TiO2 颜料粉末的工厂工人的尿液生物标志物，该粉末的平均粒径为 0.25 µm，具有超细部分，并与未暴露的工人进行了比较。研究人员在轮班前后从四十名工人、同一家公司的六名员工和同一地理区域的十八名志愿者中收集了尿液样本。通过 ICP-MS 测量了钛和其他金属的浓度，通过 HPLC/MS-MS 测量了 DNA、RNA 和蛋白质氧化产物。结果发现，轮班后工人尿液中 Al、Cd、Cr、Cu、Fe、Mn、Pb、Ti 和 Zr 的浓度以及所有氧化应激生物标志物的浓度均呈统计学显著增加。与员工和志愿者混合后，工人尿液中 Cd、Mn 和 Zr 以及氧化应激生物标志物 8-oxoGuo、8-oxodGuo 和 3NOTyr 的浓度在工作后更高。关于 TiO2 职业暴露剂量和效应生物标志物的生物监测研究提供了有用的信息，即使在符合健康和安全标准的情况下，也有助于保护工人的健康，突出了在非常低剂量下慢性暴露的可逆效应。
