Gramshaw J W, Vandenburg H J
Procter Department of Food Science, University of Leeds, UK.
Food Addit Contam. 1995 Mar-Apr;12(2):223-34. doi: 10.1080/02652039509374297.
The levels of ethylbenzene, styrene, benzene and benzaldehyde in samples of thermoset polyester were determined by dynamic headspace/gas chromatography. Styrene was present at levels from 50 to 1400 mg kg-1, ethylbenzene up to 25 mg kg-1 and benzaldehyde up to 180 mg kg-1. Benzene levels were usually less than 1 mg kg-1, but one article contained 19 mg kg-1. Levels of styrene dimers and trimers were estimated using size exclusion chromatography followed by gas chromatographic (GC) analysis and were present at approximately 100 mg kg-1 and 700 mg kg-1 respectively. The principal identified constituents of solvent extracts were stearic and palmitic acids, present at a combined level of nearly 1% by weight of the plastic. Styrene was shown to be produced by thermal depolymerization at temperatures of 175 degrees C and above. The migration of ethylbenzene and styrene into belly pork cooked in thermoset polyester dishes for 1.5 h at 175 degrees C was measured by Likens-Nickerson extraction of the cooked meat and GC/MS analysis of the extracts. Migration ranged from 6 to 2400 micrograms kg-1 for styrene and from < 6 to 34 micrograms kg-1 for ethylbenzene.
采用动态顶空/气相色谱法测定了热固性聚酯样品中乙苯、苯乙烯、苯和苯甲醛的含量。苯乙烯含量为50至1400毫克/千克，乙苯含量高达25毫克/千克，苯甲醛含量高达180毫克/千克。苯的含量通常低于1毫克/千克，但有一篇文章中的含量为19毫克/千克。采用尺寸排阻色谱法，随后进行气相色谱（GC）分析，估算了苯乙烯二聚体和三聚体的含量，其含量分别约为100毫克/千克和700毫克/千克。溶剂提取物中主要鉴定出的成分是硬脂酸和棕榈酸，其总含量占塑料重量的近1%。研究表明，在175℃及以上的温度下，热解聚反应会产生苯乙烯。通过Likens-Nickerson法提取熟肉，并对提取物进行GC/MS分析，测定了在175℃下用热固性聚酯盘烹饪1.5小时后，乙苯和苯乙烯向五花肉中的迁移量。苯乙烯的迁移量为6至2400微克/千克，乙苯的迁移量为<6至34微克/千克。
