The increasing application of reclaimed water in urban areas is a rising health concern. For instance, the inhalation of reclaimed water induces polymorphonuclear cell-dominant inflammation in the lung, and prefibrosis can develop after subchronic exposure. The major toxic source, free endotoxins, could be inhibited by chlorination, yet whether the chlorination can increase or reduce the inhalation toxicity of reclaimed water is still unclear. Here, we treated secondary effluent samples with different doses of chlorine, and then mice were exposed to these samples via inhalation. We studied inflammatory markers such as polymorphonuclear cell, proinflammatory cytokines in lung lavage, induced bronchus-associated lymphoid tissue, and immunohistochemical analysis of fibrotic markers. Results show that endotoxin activities increased slightly from 951 endotoxin units per milliliter to the highest activity of 1133 endotoxin units per milliliter after disinfection. However, pulmonary inflammation was reduced after 5 and 10 mg/L chlorine treatment. The aggregate size of endotoxin displayed a decline after chlorination. Furthermore, the potential cytotoxicity of the disinfection byproducts after chlorination was not observed in the lungs after subchronic exposure. This study demonstrates that sufficient chlorination can prevent acute and subchronic pulmonary damage caused by the reclaimed water. In addition, endotoxin activity should not be used as an index for acute and subchronic toxicity control.

在城市地区越来越多地使用再生水是一个日益严重的健康问题。例如，吸入再生水会在肺中诱发以多形核细胞为主的炎症，并且在亚慢性接触后会发展成纤维化前体。氯化可以抑制主要毒源游离内毒素，但氯化是否可以增加或降低再生水的吸入毒性尚不清楚。在这里，我们用不同剂量的氯处理二次流出液样品，然后通过吸入将小鼠暴露于这些样品中。我们研究了炎症标志物，如多形核细胞、肺灌洗液中的促炎细胞因子、诱导的支气管相关淋巴组织和纤维化标志物的免疫组织化学分析。结果表明，消毒后内毒素活性从每毫升 951 个内毒素单位略微增加到每毫升 1133 个内毒素单位的最高活性。然而，在 5 和 10 mg/L 氯处理后肺部炎症有所减轻。氯化后内毒素的聚集体大小有所下降。此外，在亚慢性暴露后的肺中未观察到氯化后消毒副产物的潜在细胞毒性。这项研究表明，足够的氯化可以预防再生水引起的急性和亚慢性肺损伤。此外，内毒素活性不应作为急性和亚慢性毒性控制的指标。5 和 10 mg/L 氯处理后肺部炎症有所减轻。氯化后内毒素的聚集体大小有所下降。此外，在亚慢性暴露后的肺中未观察到氯化后消毒副产物的潜在细胞毒性。这项研究表明，足够的氯化可以预防再生水引起的急性和亚慢性肺损伤。此外，内毒素活性不应作为急性和亚慢性毒性控制的指标。5 和 10 mg/L 氯处理后肺部炎症有所减轻。氯化后内毒素的聚集体大小有所下降。此外，在亚慢性暴露后的肺中未观察到氯化后消毒副产物的潜在细胞毒性。这项研究表明，足够的氯化可以预防再生水引起的急性和亚慢性肺损伤。此外，内毒素活性不应作为急性和亚慢性毒性控制的指标。这项研究表明，足够的氯化可以预防再生水引起的急性和亚慢性肺损伤。此外，内毒素活性不应作为急性和亚慢性毒性控制的指标。这项研究表明，足够的氯化可以预防再生水引起的急性和亚慢性肺损伤。此外，内毒素活性不应作为急性和亚慢性毒性控制的指标。