Leaching of Silver from Silver-Impregnated Food Storage Containers

Abstract

The use of silver in commercial products has proliferated in recent years owing to its antibacterial properties. Food containers impregnated with micro-sized silver promise long food life, but there is some concern because silver can leach out of the plastic and into the stored food. This laboratory experiment gives students the opportunity to design their own study to measure the leached silver via graphite furnace atomic absorption spectrophotometry. In this experiment, students stored deionized water, tap water, and acetic acid in two styles of silver food containers for a week. The less expensive version of the food container consistently had higher levels of leached silver. The acetic acid samples and microwaved samples also had higher silver levels. Students gained experience with sample design, chemical analysis, and data analysis.

Review of nanomaterial aging and transformations through the life cycle of nano-enhanced products

“…The ENPs would experience a similar fate as consumption, outlined above. Migration of Ag ENPs from plastic bags into food simulants was studied by Huang et al and Hauri et al, where Ag-impregnated plastic food containers were shown to release a maximum Ag concentration of 0.9 mg/L in 5% acetic acid after seven days Hauri and Niece, 2011). However, in both studies Ag form was not determined.…”

Release of nanomaterials from solid nanocomposites and consumer exposure assessment – a forward-looking review

“…Because of the antimicrobial properties of AgNPs, they are applied as inner coatings for various food storage containers, such as plastic bags or boxes to keep the food fresh longer (The Project on Emerging Nanotechnologies (PEN), 2013). Several studies have attempted to characterize and quantify the silver content in such products (von Goetz et al, 2013b;Huang et al, 2011), as well as determine the release of Ag in various food simulants (Huang et al, 2011;von Goetz et al, 2013b;Hauri and Niece, 2011).…”

“…General trend was that release rates were increasing with higher temperatures and longer storage time (Huang et al, 2011). Another study (a student experiment) used commercially available plastic food containers that contained Ag and also found that acetic acid results in higher release rates in comparison to ethanol or distilled water, however, they did not quantify the initial Ag content of the containers or use any control as reference (Hauri and Niece, 2011). Von Goetz et al (2013b) and Artiaga et al (2014) had also chosen commercially available food storage materials for their migration experiments sharing a similar test setup, choosing instead of using food containers intact, having them cut in pieces and exposed to food simulants.…”

Silver nanoparticle release from commercially available plastic food containers into food simulants

“…There have been attempts to quantify the total Ag release rates from various consumer products, including food contact materials (von Goetz et al 2013;Huang et al 2011;Hauri and Niece 2011;Song et al 2011;Bott et al 2011;Smirnova et al 2012;Echegoyen and Nerín 2013;Cushen et al 2014;Artiaga et al 2014).…”

“…Another study by Hauri and Niece (2011) used a similar release setup and tested commercially available plastic food storage containers advertised as containing AgNPs and found that acetic acid resulted in higher Ag release rates compared to ethanol and distilled water. However, Hauri and Niece (2011) did not quantify the initial Ag content of the food containers or the Ag release in the nanoparticulate form. Again, using a similar setup, experimental studies by von Goetz et al (2013) and Artiaga et al (2014) also chose to test the migration of AgNPs from commercially available food storage materials.…”