Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Azabu University, 1-17-71 Fuchinobe, Chuo-Ku, Sagamihara-Shi, Kanagawa, 2525201, Japan.
Institute of Technology, Shimizu Corporation, 3-4-17 Etchujima, Koto-Ku, Tokyo, Japan.
Arch Toxicol. 2023 Dec;97(12):3151-3162. doi: 10.1007/s00204-023-03593-2. Epub 2023 Sep 21.
Ozone gas is widely used in hospitals as well as homes to control COVID-19 infection owing to its cost-effectiveness. Safety standard value and the tolerable value of ozone gas are set at 0.05 ppm and 0.1 ppm, respectively, in developed countries; however, this value was principally determined for healthy individuals, and the risks associated with ozone gas inhalation in patients with pulmonary diseases remains unknown. Recently, we demonstrated that 0.1 ppm ozone gas exposure significantly aggravates the symptoms of acute lung injury in mice. In the present study, we further examined the influence of ≤ 0.1 ppm ozone gas exposure on percutaneous oxygen saturation (SpO) and pro-inflammatory responses in a mouse model of asthma. Female BALB/c mice were subjected to repetitive intranasal sensitization of Dermatophagoides farinae to generate a mouse model of asthma. Inhalation exposure of ozone gas (0.1, 0.03, 0.01 ppm), generated using an ultraviolet lamp, was performed for five consecutive days immediately before the final sacrifice. There were no abnormal findings in control mice exposed to 0.1 ppm ozone; however, 0.1 ppm ozone exposure significantly reduced the SpO level in asthmatic mice. Histological evaluation and gene expression analysis revealed that pro-inflammatory cytokine levels were significantly increased in mice exposed to 0.1 ppm ozone, indicating that 0.1 ppm ozone exposure affects the development of asthma symptoms. Notably, 0.03 and 0.01 ppm ozone exposure did not have any effects even in asthmatic mice. Our findings indicate that the tolerable level of ozone gas should be adjusted for individuals based on a history of respiratory disorders.
臭氧气体由于其成本效益，被广泛应用于医院和家庭以控制 COVID-19 感染。在发达国家，臭氧气体的安全标准值和可耐受值分别设定为 0.05ppm 和 0.1ppm；然而，这一数值主要是针对健康个体确定的，患有肺部疾病的患者吸入臭氧气体的风险尚不清楚。最近，我们证明了 0.1ppm 的臭氧气体暴露会显著加重小鼠急性肺损伤的症状。在本研究中，我们进一步研究了≤0.1ppm 的臭氧气体暴露对哮喘小鼠经皮血氧饱和度（SpO）和促炎反应的影响。雌性 BALB/c 小鼠经反复鼻内敏化屋尘螨，生成哮喘小鼠模型。使用紫外线灯产生的臭氧气体（0.1、0.03、0.01ppm）进行连续 5 天的吸入暴露，在最后一次处死前进行。暴露于 0.1ppm 臭氧的对照组小鼠未出现异常发现；然而，0.1ppm 的臭氧暴露显著降低了哮喘小鼠的 SpO 水平。组织学评估和基因表达分析显示，暴露于 0.1ppm 臭氧的小鼠促炎细胞因子水平显著升高，表明 0.1ppm 臭氧暴露影响哮喘症状的发展。值得注意的是，即使在哮喘小鼠中，0.03 和 0.01ppm 的臭氧暴露也没有任何影响。我们的研究结果表明，臭氧气体的可耐受水平应根据个体的呼吸系统疾病史进行调整。
