Abstract:
As a widely used secondary vulcanization accelerator in the rubber industry, 1,3-diphenylguanidine (DPG) poses risks to human health and the environment. To compare and comprehend the disinfection process of DPG, this work investigates the reaction kinetics, toxicity, and transformation products (TPs) of DPG during chlorination and monochloramination. It has been revealed that the reactivity of monochloramine is significantly slower compared to chlorination of DPG, with the maximum efficiency observed at pH 7 to pH 8. Cytotoxicity assessment using HepG2 and THP-1 cells reveals that cytotoxicity hierarchy is as follows: chlorine TPs > monochloramine TPs > DPG. Moreover, oxidant-to-DPG molar ratios 10 and 20 lead to higher cytotoxicity in both chlorination and monochloramination compared to ratio 5 and 100. Additionally, cell bioenergetics experiments demonstrate that chlorine and monochloramine TPs induce mitochondrial dysfunction and enhance glycolytic function in HepG2 cells. The genotoxic response from p53 signaling further suggested genotoxic effects of certain TPs. Furthermore, analysis of TPs using high-resolution mass spectrometry (HRMS) identifies ten TPs, with chlorination yielding more TPs than monochloramination. Generally, a chlorine or monochloramine molar ratio to DPG of 10-20 results in an increased formation of TPs and heightened cytotoxicity. Notably, higher oxidant molar ratios increased the formation of monoguanidine TPs and DPG hydroxylation during chlorination, whereas monochloramination lead to DPG substitution predominantly generating chlorinated DPG due to weaker oxidation effects. These findings provide valuable information for the appropriate treatment of DPG and disinfection processes in water facilities to mitigate potential risks to human health and the ecosystem.
摘要:
作为橡胶工业中广泛使用的二次硫化促进剂,1,3-二苯基胍(DPG)对人类健康和环境构成风险。为了比较和理解DPG的消毒过程,这项工作研究了反应动力学,毒性,以及氯化和一氯胺化过程中DPG的转化产物(TP)。据透露,与DPG的氯化相比,一氯胺的反应性明显较慢,在pH7至pH8时观察到最大效率。使用HepG2和THP-1细胞的细胞毒性评估显示细胞毒性等级如下:氯TP>一氯胺TP>DPG。此外,与比率5和100相比,氧化剂与DPG的摩尔比10和20在氯化和单氯胺化中导致更高的细胞毒性。此外,细胞生物能学实验表明,氯和一氯胺TP诱导线粒体功能障碍并增强HepG2细胞的糖酵解功能。来自p53信号传导的基因毒性反应进一步提示某些TP的基因毒性作用。此外,使用高分辨率质谱(HRMS)分析TP可识别10个TP,氯化比单氯胺化产生更多的TP。一般来说,10-20的氯或一氯胺与DPG的摩尔比导致TP的形成增加和细胞毒性增强。值得注意的是,较高的氧化剂摩尔比增加了氯化过程中单胍TP和DPG羟基化的形成,而一氯胺化导致DPG取代主要由于较弱的氧化作用而产生氯化DPG。这些发现为水设施中DPG的适当处理和消毒过程提供了有价值的信息,以减轻对人类健康和生态系统的潜在风险。