Abstract
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°C and above. The migration of ethylbenzene and styrene into belly pork cooked in thermoset polyester dishes for 1.5 h at 175°C was measured by Likens‐Nickerson extraction of the cooked meat and GC/MS analysis of the extracts. Migration ranged from 6 to 2400 μg kg−1 for styrene and from < 6 to 34 μg kg−1 for ethylbenzene.