The juvenile employee was charged in April with reckless endangerment and criminal mischief.
Police say a total of 11 needles were placed into merchandise, including bagged vegetables, Tastykakes, pouches of tuna and bread rolls purchased at the store.
No injuries were reported.
The incidents happened at the Giant at 7150 Hamilton Boulevard in Lower Macungie Township.
Officials say the case is now being handled by a juvenile court.