At present, priority pollutants in printing and dyeing wastewater have attracted increasing attention, but their types and limits in the wastewater discharge standards for China's dyeing and finishing industry are still lacking. This study selected 9 printing and dyeing enterprises in a region of Zhejiang Province as the research objects. Through literature collection, field investigations, and chemical analysis, combined with industry priority pollutant screening technology, 103 and 21 characteristic pollutants were selected as preliminary and supplementary lists of priority pollutants, respectively. The results of the pollutant category analysis revealed that 55% of the pollutants on the preliminary list included carcinogens, and 29% of the pollutants on the supplementary list included alcohols. According to the four rules for in-depth screening, a total of 23 indicators (excluding those in GB 4287-2012 and its revised versions) were selected as the final list of priority pollutants, most of which were polycyclic aromatic hydrocarbons (PAHs) but also included a small number of lipid substances, such as bis (2-ethylhexyl) phthalate. The screening of these indicators not only provides data support for the expansion of water pollution control indicators and the determination of their limits in China's printing and dyeing industry, but also promotes the supplementation and improvement of the sewage discharge standard system in related industries.
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