Chemical Characterization of Recycled Consumer Products Using Suspect Screening Analysis

Recycled materials are found in many consumer products as part of a circular economy; however, the chemical content of recycled products is generally uncharacterized. A suspect screening analysis using two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOFMS) was applied to 210 products (154 recycled, 56 virgin) across seven categories. Chemicals in products were tentatively identified using a standard spectral library or confirmed using chemical standards. A total of 918 probable chemical structures identified (112 of which were confirmed) in recycled materials versus 587 (110 confirmed) in virgin materials. Identified chemicals were characterized in terms of their functional use and structural class. Recycled paper products and construction materials contained greater numbers of chemicals than virgin products; 733 identified chemicals had greater occurrence in recycled compared to virgin materials. Products made from recycled materials contained greater numbers of fragrances, flame retardants, solvents, biocides, and dyes. The results were clustered to identify groups of chemicals potentially associated with unique chemical sources, and identified chemicals were prioritized for further study using high-throughput hazard and exposure information. While occurrence is not necessarily indicative of risk, these results can be used to inform the expansion of existing models or identify exposure pathways currently neglected in exposure assessments.

循环经济背景下，再生材料已广泛应用于各类消费品中，但目前多数再生产品的化学组成尚未得到系统表征。本研究针对七大品类共210件产品（其中154件为再生材料制品、56件为原生材料制品），采用二维气相色谱-飞行时间质谱法（two-dimensional gas chromatography time-of-flight mass spectrometry, GC × GC-TOFMS）开展可疑物筛查分析。研究中，产品中的化学物质先通过标准光谱库进行初步定性，部分物质再通过化学标准品进行确证。最终在再生材料制品中共鉴定出918种潜在化学结构（其中112种经确证），原生材料制品中则鉴定出587种（其中110种经确证）。研究对鉴定出的化学物质按其功能用途与结构类别进行了分类表征。再生纸制品与建筑材料中含有的化学物质数量多于同品类原生制品；相较于原生材料制品，再生材料制品中有733种鉴定出的化学物质检出频率更高。再生材料制品中还含有更多的香料、阻燃剂、溶剂、杀菌剂与染料。研究对鉴定结果进行聚类分析，以识别与特定化学来源相关的化学物质群组；同时结合高通量毒性与暴露信息，对已鉴定的化学物质进行优先级排序，以供后续研究。尽管化学物质的检出频率未必代表风险，但本研究结果可为现有模型的拓展提供参考，或可帮助识别当前暴露评估中被忽略的暴露途径。