Identification of Diisobutyl Phthalate (DIBP) Suspected as Possible Contaminant in Recycled Cellulose for Take-away Pizza Boxes

Italian law specifically requires the use of virgin, rather than recycled, cellulose in the production of pizza boxes. We investigated the frequent failure to comply with this law: the identification and determination of phthalates, which have widespread use, contribute to the quality control of various food packaging materials. Diisobutyl phthalate (DIBP) has similar structural and application properties to di-n-butyl-phthlate (DBP), and it is used as a substitute for DBP. We standardized an analytical method that allows the calculation of an ‘exposure index’ (EI) for DIBP in take-away pizza boxes. The technique, which relies on Solid-Phase Micro Extraction/Gas Chromatography/Mass Spectrometry (SPME/GC/MS), allows the definition of a large range of DIBP content in the headspace within various take-away pizza boxes. Data concerning pizza boxes purchased in 16 restaurants in 2006 were reported, and the ‘EIs’ were estimated to range between 6 and 72 microg.