State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Science, Beijing 100085, China; Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Jinan University, Guangzhou 511443, China.
Quality Management Center, National Institutes for Food and Drug Control, Beijing 102629, China.
J Hazard Mater. 2022 Jun 15;432:128652. doi: 10.1016/j.jhazmat.2022.128652. Epub 2022 Mar 8.
Melamine and its derivatives are used as additives in flame retardants. Moreover, melamine-containing consumables such as laminates, adhesives, glues, and plastics are extensively used in electronic products. Nevertheless, there is no information concerning the identification of melamine and its derivatives during e-waste recycling. In the present study, the occurrence of melamine and three of its derivatives (cyanuric acid, ammelide, and ammeline) was identified for the first time in indoor dust from typical e-waste recycling areas and adjacent rural communities. Urban communities situated about 80 kilometers away were used as a control. The target analytes were detected in almost all the dust samples, which were dominated by melamine and cyanuric acid. The total concentrations of melamine and its derivatives varied among sampling locations in the following order: e-waste workshops (geometric mean: 15,018 ng/g) > urban houses (9060 ng/g) > local rural houses (6204 ng/g) > local streets (201 ng/g). This suggested that e-waste dismantling/recycling activities mainly contributed to the abundant emission of melamine and its derivatives in e-waste dust. Correlation analysis indicated that melamine and its derivatives were similarly applied in electronic products and e-waste recycling resulted in common emissions. The combined toxicity of melamine and its derivatives on human bladder cancer cells was observed. Importantly, Monte Carlo analysis was used to determine that the estimated daily intakes of these chemicals via dust ingestion for occupational e-waste recycling workers were 2.5-9 times higher than the estimated daily intakes for adult residents in both adjacent local communities and urban areas. These results are the first to demonstrate that e-waste dismantling workers are more vulnerable to the exposure risk posed by the presence of melamine and its derivatives in e-waste dust, which deserves more research attention.
三聚氰胺及其衍生物被用作阻燃剂的添加剂。此外，含有三聚氰胺的消费品，如层压板、粘合剂、胶水和塑料，广泛应用于电子产品中。然而，在电子废物回收过程中，没有关于三聚氰胺及其衍生物的识别信息。在本研究中，首次在典型电子废物回收区和相邻农村社区的室内灰尘中发现了三聚氰胺及其三种衍生物（氰尿酸、三聚氰胺酰胺和三聚氰胺脒）的存在。距离约 80 公里的城市社区被用作对照。在几乎所有的灰尘样本中都检测到了目标分析物，其中以三聚氰胺和氰尿酸为主。三聚氰胺及其衍生物的总浓度在采样地点的顺序如下：电子废物车间（几何平均值：15018ng/g）>城市房屋（9060ng/g）>当地农村房屋（6204ng/g）>当地街道（201ng/g）。这表明电子废物拆解/回收活动主要导致电子废物灰尘中三聚氰胺及其衍生物的大量排放。相关分析表明，三聚氰胺及其衍生物在电子产品中具有相似的应用，而电子废物回收导致了共同的排放。观察到三聚氰胺及其衍生物对人膀胱癌细胞的联合毒性。重要的是，使用蒙特卡罗分析确定，职业性电子废物回收工人通过灰尘摄入这些化学物质的估计每日摄入量比相邻当地社区和城市地区成年居民的估计每日摄入量高 2.5-9 倍。这些结果首次表明，电子废物拆解工人更容易受到电子废物灰尘中三聚氰胺及其衍生物存在带来的暴露风险的影响，这值得更多的研究关注。
