Screening and Semi-quantification of Semi-volatile Contaminants from Recycled High-density Polyethylene Flakes
The work aims to qualitatively and quantitatively analyze semi-volatile pollutants in 25 different sources of recycled high-density polyethylene(rHDPE),so as to explore potential hazardous substances in rHDPE.Semi-volatile organic compounds were extracted using dichloromethane,and then qualitatively analyzed by gas chromatography-mass spectrometry in combination with NIST20 mass spectral library and retention indices.Semi-quantification was done based on reference standards selected according to structural similarity calculated by molecular descriptors and random forest algorithm.A total of 114 substances were detected in these 25 samples,with each sample containing 42 to 89 substances,with median concentrations ranging from 34 to 97 mg/kg.Common substances included alkenes typical in polyolefins,antioxidants,lubricants,and their transformation products.Among the high-concern substances,diisobutyl phthalate and nonylphenol were detected in over 50％of samples,with average concentrations exceeding 8 mg/kg.Although 1-tetradecene was not classified as a high-concern substance,its specific migration limit is only 0.05 mg/kg,while its average concentrat is 59 mg/kg,posing a potential migration risk.These results indicate that there are certain high-concern contaminants present in rHDPE fragments,which may pose potential risks to food safety when used as recycled packaging materials.
万方数据
维普
