A syringe was found in the aisles of the Coles supermarket at Swan Hill late last month.
Freda Noonan was shopping with her granddaughter when she saw the needle on December 30.
Ms Noonan said that it was a very quiet day at the supermarket, with hardly any shoppers around.
"I said look that looks like a syringe and it was. (The needle) was roughly opposite the toilets," she said.
"I would have to say I definitely do think it's a sign of a wider problem in Swan Hill."
To read more about this story, grab a copy of Wednesday's Guardian (January 11).