State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, Jiangsu, 215123, China.
Department of nursing administration, The Second Affiliated Hospital of Soochow University, Suzhou, 215004, China.
Chemosphere. 2024 Sep;364:143205. doi: 10.1016/j.chemosphere.2024.143205. Epub 2024 Aug 28.
The extensive use of synthetic antioxidants, notably N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6-PPD), in rubber-related products, particularly in tire manufacturing, has induced concerns regarding their environmental impact and potential health hazards. Despite the identification of 6-PPD and its derivative, 6-PPD quinone (6-PPDQ), in various water samples and their lethal effects on certain aquatic species (e.g., coho salmon, rainbow trout and brook trout), the levels of airborne 6-PPD/6-PPDQ and their respiratory toxicity remain relatively unexplored. In this study, we aimed to evaluate the respiratory toxicity potential of 6-PPD and its derivatives, with a specific focus on detecting these compounds in airborne particulates and assessing their toxic effects on lung cells. Characterization of four airborne fine particulate (FP) samples revealed spherical morphologies with diameters ranging from 17.7 to 225.7 nm, displaying slight agglomeration and negative surface charge. methanol/acetonitrile extraction followed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analysis confirmed the presence of both 6-PPD and 6-PPDQ on the surfaces of FPs, with significant variations (0.26-1.05 μg g) in loading capacity observed among the samples. Subsequent exposure of lung cells (THP-1, BEAS-2B, and A549) to 6-PPD and 6-PPDQ revealed dose-dependent declines in mitochondrial metabolic activity induced by 6-PPD, along with severe membrane damage, ATP depletion, and pro-inflammatory cytokine release. Conversely, 6-PPDQ exhibited negligible toxicity in all tested parameters. These findings underscore the potential health risks associated with airborne 6-PPD exposure and emphasize the importance of further research into the respiratory toxicity of 6-PPD derivatives.
广泛使用合成抗氧化剂，特别是 N-(1,3-二甲基丁基)-N'-苯基-对苯二胺（6-PPD），用于橡胶相关产品，特别是轮胎制造，引起了人们对其环境影响和潜在健康危害的关注。尽管已经在各种水样中发现了 6-PPD 及其衍生物 6-PPD 醌（6-PPDQ），并且它们对某些水生物种（如银鲑、虹鳟和溪红点鲑）具有致死作用，但空气中的 6-PPD/6-PPDQ 水平及其呼吸毒性仍然相对未知。在这项研究中，我们旨在评估 6-PPD 及其衍生物的呼吸毒性潜力，特别关注检测空气中的这些化合物并评估它们对肺细胞的毒性作用。对四个空气细颗粒物（FP）样品的特征描述表明，它们具有 17.7 至 225.7nm 的直径，呈现出轻微聚集和负表面电荷的球形形态。甲醇/乙腈提取后，采用液相色谱-串联质谱（LC-MS/MS）分析，证实了 FP 表面存在 6-PPD 和 6-PPDQ，样品之间的载量存在显著差异（0.26-1.05μg g）。随后，将肺细胞（THP-1、BEAS-2B 和 A549）暴露于 6-PPD 和 6-PPDQ 中，结果表明 6-PPD 会导致线粒体代谢活性的剂量依赖性下降，同时还会导致严重的膜损伤、ATP 耗竭和促炎细胞因子的释放。相反，6-PPDQ 在所有测试参数中都表现出微不足道的毒性。这些发现突显了空气中 6-PPD 暴露所带来的潜在健康风险，并强调了进一步研究 6-PPD 衍生物呼吸毒性的重要性。
