The results for the ICP-MS analysis of samples stored on
nano- silver coated films after incubation at 40 c are presented in Fig. 1. These demonstrate a slightly higher level of migration compared with food samples stored in nano-silver containers. The highest level of migration recorded after conducting replicate
experiments, representing an orange juice sample stored for
7 & 10 days, corresponds to values of 18.95 & 28.92 ± 0.01 mgL1, respectively. These levels are raised in comparison to other samples which possess higher pH under the same conditions and incubated in the presence of the same packaging material, hence indicating that the pH of the foodstuff has an impact on the migration rate of ENPs into food. Conversely, the concentration of silver recorded in the associated control sample was 0.41 ± 0.02 mgL1. The results for samples stored in nano-silver containers are presented in Fig. 2 and in this case silver migration appears considerably lower than for samples stored over nano-silver coated films; orange juice samples stored in nano-silver containers for
7 & 10 days gave 3.17 & 5.66 ± 0.02 mgL1, respectively. This level is considered higher than for other samples stored in the same packaging and under the same conditions (see Fig. 2). In comparison, the migration level for water samples stored over coated films for 6 weeks is presented in Fig. 3 and corresponds to 6.4 ± 0.01 mgL1, demonstrating a rapid increase in silver migration during the first 2 weeks of storage. When the same samples were stored using nano-silver containers the level of migration was not significant until the fourth week of storage. Similar results are also reported by Hill, Liper, and Porter (2010), in their study the release of colloidal silver into water samples in contact with silver antimicrobial filters was determined as