Sodium dimethyldithiocarbamate (SDDC) is a widely used heavy metal chelating agent in harmless treatment of wastewater and hazardous waste, but SDDC and its heavy metal chelates may leak into the environment and bring potential ecological risks. In this study, the model organism Caenorhabditis elegans was used to evaluate the toxic effect of SDDC and its heavy metal Cu, Pb chelates. Multiple endpoints were investigated by subacute exposure to SDDC (0.01-100 mg/L) and micro-sized Cu, Pb chelates of SDDC (1-100 mg/L). Our data indicated that the LC50 value of SDDC was 139.39 mg/L (95% Cl: 111.03, 174.75 mg/L). In addition, SDDC was found that concentration of 1 mg/L is a safe limit value for nematode C. elegans, and concentration above 1 mg/L caused adverse effects on the survival, growth, locomotion behaviors and reactive oxygen species (ROS) production of exposed nematodes. Furthermore, all tested SDDC-Cu and SDDC-Pb chelates had obviously lower toxic effect than untreated Cu, Pb metals. These two chelates also had a lower toxic effect than SDDC agent due to its more stable structure. Moreover, SDDC-Cu had a higher toxic effect than SDDC-Pb at the same concentration. Thus, our results suggest that SDDC as a kind of chelating agent applied in harmless treatment of heavy metals, the safe addition limit should not be exceeded.

中文翻译：

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秀丽隐杆线虫中二甲基二硫代氨基甲酸钠及其微细金属螯合物的生态毒性评估。

二甲基二硫代氨基甲酸钠（SDDC）是无害处理废水和危险废物中广泛使用的重金属螯合剂，但SDDC及其重金属螯合物可能泄漏到环境中并带来潜在的生态风险。在这项研究中，模型生物秀丽隐杆线虫被用于评估SDDC及其重金属Cu，Pb螯合物的毒性作用。通过亚急性暴露于SDDC（0.01-100 mg / L）和SDDC的微米尺寸Cu，Pb螯合物（1-100 mg / L）来研究多个终点。我们的数据表明SDDC的LC50值为139.39 mg / L（95％Cl：111.03，174.75 mg / L）。此外，SDDC还发现线虫秀丽线虫的安全限值为1 mg / L，而浓度超过1 mg / L会对线虫的存活，生长产生不利影响，裸露线虫的运动行为和活性氧（ROS）的产生。此外，所有测试的SDDC-Cu和SDDC-Pb螯合物的毒性作用均明显低于未处理的Cu，Pb金属。由于其更稳定的结构，这两种螯合物还具有比SDDC剂更低的毒性作用。此外，在相同浓度下，SDDC-Cu具有比SDDC-Pb更高的毒性作用。因此，我们的结果表明，SDDC作为一种用于重金属无害化处理的螯合剂，不应超过安全添加限量。在相同浓度下，SDDC-Cu具有比SDDC-Pb更高的毒性作用。因此，我们的结果表明，SDDC作为一种用于重金属无害化处理的螯合剂，不应超过安全添加限量。在相同浓度下，SDDC-Cu具有比SDDC-Pb更高的毒性作用。因此，我们的结果表明，SDDC作为一种用于重金属无害化处理的螯合剂，不应超过安全添加限量。