Migration of di-(2-ethylhexyl)adipate and acetyltributyl citrate plasticizers from food-grade PVC film into isooctane: Effect of gamma radiation Panagiota D. Zygoura a , Antonios E. Goulas b , Kyriakos A. Riganakos a , Michael G. Kontominas a, * a Laboratory of Food Chemistry and Technology, Department of Chemistry, University of Ioannina, Ioannina 45110, Greece b Department of Materials Science and Technology, University of Ioannina, Ioannina 45110, Greece Received 17 April 2005; received in revised form 15 November 2005; accepted 1 December 2005 Available online 26 January 2006 Abstract The effect of gamma radiation on the migration of both di-(2-ethylhexyl)adipate (DEHA) and acetyltributyl citrate (ATBC) plasti- cizers from PVC film into the food simulant isooctane was studied as a function of time (0–48 h) at 20 °C. Food-grade PVC cling-film used contained 5.3% (w/w) DEHA, 3.0% (w/w) ATBC and polyadipate polymeric plasticizer. Irradiation of the films was carried out at doses of 5, 10 and 25 kGy using a [ 60 Co] gamma-radiation source. Determination of both plasticizers was performed using a direct gas chromatographic method. No radiation-induced transformation of the two plasticizers was observed after absorbed doses of 5–25 kGy. DEHA migrated rapidly into isooctane in contrast with ATBC. ATBC migrating amounts at equilibrium were approximately three times lower than the corresponding amounts of DEHA. Irradiation at doses 10 and 25 kGy had a small but statistically significant (P < 0.05) effect on the migration of both DEHA and ATBC into isooctane. Migration amount increased with increasing irradiation dose and con- tact time. The irradiation-induced increase of ATBC migration was significantly higher than the corresponding increase of DEHA migra- tion. Results are discussed in relation to EU proposed upper limit for DEHA specific migration (18 mg/L). Diffusion coefficients for both plasticizers calculated, showed differences between irradiated and control samples. Ó 2005 Elsevier Ltd. All rights reserved. Keywords: PVC; Fatty food simulant; Gamma radiation; Diffusion coefficients 1. Introduction Plasticizers are low molecular weight synthetic organic molecules added to the polymer resin to modify properties such as flexibility and processibility. Such additives nor- mally possess a high mobility due to relatively low molecu- lar weight and easily diffuse to the surrounding media (food, solvent etc.) particularly those with a high fat content (Coo- per, Goodson, & O’Brien, 1998; Goulas & Kontominas, 1996; Goulas, Anifantaki, Kolioulis, & Kontominas, 2000; Lau & Wong, 2000; Tsumura, Ishimitsu, Kaihara, Yoshii, & Tonogai, 2002). There are many studies published in the literature on the migration of plasticizers from poly(vinyl chloride) (PVC) (flexible films, children toys, gaskets, blood and serum stor- age bags etc.) into foods, food simulants and saliva simu- lants (Cooper et al., 1998; Fantoni & Simoneau, 2003; Goulas et al., 2000; Goulas, Kokkinos, & Kontominas, 1995; Goulas & Kontominas, 1996; Goulas, Riganakos, Ehlermann, Demertzis, & Kontominas, 1998; Hammar- ling, Gustavsson, Svensson, Karlsson, & Oskarsson, 1998; Hirayama, Tanaka, Kawana, Tani, & Nakazawa, 2001; Lakshmi & Jayakrishnan, 1998; Nerin, Gancedo, & Cacho, 1992; Petersen, Naamansen, & Nielsen, 1995; 0260-8774/$ - see front matter Ó 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.jfoodeng.2005.12.004 * Corresponding author. Tel.: +30 26510 98342; fax: +30 26510 98795. E-mail address: mkontomi@cc.uoi.gr (M.G. Kontominas). www.elsevier.com/locate/jfoodeng Journal of Food Engineering 78 (2007) 870–877