Leaching of Silver from Silver-Impregnated Food Storage Containers

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.