印染末端废水中全氟化合物的污染特征、影响因素及风险评价

Occurrence, influencing factors, and risks assessment of perfluorinated compounds (PFCs) in wastewater from textile and dyeing industry

全氟化合物(Perfluorinated compounds,PFCs)常被作为织物整理剂和表面活性剂应用于纺织印染行业,通过末端处理排放进入水体环境,对生态安全产生直接影响.本研究采集我国长三角地区58家纺织印染厂的调节池原水和末端排放尾水样品,建立固相萃取-超高效液相色谱串联质谱法(SPE-UPLC-MS/MS)对8种短中链全氟化合物(C4~C8)进行分析,探明印染废水PFCs的污染特征.结果表明,8种目标化合物在废水样本中检出率为38.9%~100.0%,原水中PFCs浓度为29.37~4518.27 ng·L^(-1),末端尾水中PFCs浓度为8.82~3995.76 ng·L^(-1),其中PFOA是首要的污染物.传统的废水处理工艺对短中链全氟化合物有一定去除作用,去除率最高可达79.9%.Kruskal-Wallis检验发现PFOA、PFHpA及PFHxA在以化纤为原料的生产过程中残留水平显著高于其他材料.Spearman相关性分析及主成分分析显示,官能团结构、碳链长度和前体物质降解是影响其来源的主要因素.生态风险分析结果表明,PFOA和PFOS的风险商值均小于1,尚未达到对生态环境和水生生物具有风险的水平.

Perfluorinated compounds(PFCs) have been widely applied in the textile industry as finishing agents and surfactants. PFCs generated during the manufacturing wastewater are a potential threat to ecological safety. In this study, raw water of regulation tank and tail water of end-of-pipe treatment were sampled from 58 printing and dyeing factories in Yangtze River Delta. Eight short-and medium-chain PFCs(C4~C8) were identified by using Solid-phase extraction-UPLC/MSMS method. The target compounds were widely distributed in the textile wastewaters with their detection frequencies of 38.9%~100.0%. The total concentrations of PFCs in raw and tail water samples ranged 29.37~4518.27 ng·L^(-1) and 8.82~3995.76 ng·L^(-1), respectively, which PFOA was the predominant contributor. PFCs were not exclusively removed by the traditional treatment process as the highest removal ratio was up to 79.9%. Kruskal-Wallis test results found that the residual of PFOA, PFHpA, and PFHxA in the production process using chemical fiber as raw materials were significantly higher than those of other materials. The Spearman correlation analysis and principal component analysis results showed that the structure of the functional group, carbon-chain length, and degradation of precursor are the main factors affecting the source. Risk assessment suggested that the risk quotients of PFOA and PFOS were both lower than 1, which had not reached the level of risk to the ecological environment and aquatic organisms.