Suggestions on revising the limit values of persistent organic pollutants in hazardous waste identification

Persistent Organic Pollutants (POPs) have been frequently detected in various environmental media and human tissues, and have received significant attention from environmental researchers. Solid waste is an important source and sink of POPs. Scientific and rational disposal of POPs-containing solid wastes is of great significance to control and reduce the environmental hazards of POPs. With the updating of the list of Stockholm Convention on Persistent Organic Pollutants (POPs), the current version of China's Identification Standards for Hazardous Waste - Identification for Toxic Substance Content (GB 5085.6-2007) needs to be revised and improved in a timely manner. In view of this demand, the management limit requirements for the POPs-containing solid wastes at home and abroad were summarized, and the status of POPs residues in typical solid wastes and related samples in China was reviewed. The results showed that most solid wastes, environmental samples, or organisms contained POPs at levels ranging from one part per billion to one part per million. The levels of some POPs were close to or up to one part per thousand in samples with larger applications. Among them, the levels of polybrominated diphenyl ethers, pentachlorophenol, and short-chained chlorinated paraffins in solid wastes might be at risk of exceeding the management limits. Combined with the existing methodology for hazardous waste identification standard development in China and comprehensively considering the technical feasibility and socio-economic impact of factors, the recommended revised limits for the identification of toxic substance content for 19 POPs listed in Priority Control List of Emerging Contaminants (2023 version) were given.