Needles can often be hidden among letters in post boxes
Postal workers in Derby are being warned to take care after a rise in the number of used syringes being found in post boxes.
Although the problem has existed for some years, Lisa Clark from the Communication Workers Union said reports in Derby were increasing.
Needles have most recently been found posted through the box on Hartington Street, Ms Clark said.
Postal workers have been issued with leather gloves to help protect them.
No crime committed
"If it's a busy box, nine times out of 10, you can't see anything when you're emptying the post until you get to the bottom and sometimes it can be too late," said Ms Clark.
But she added no workers in Derby had been pricked by a needle for about 10 years.
"It's not really a crime being committed, but we tell members who find needles either to empty the box very carefully and separate the bag for further checks or to ring their manager who will send someone to help sort it out.
"Our workers do have a right to refuse to collect post if they find needles, but they do have a duty to inform the managers."
Ms Clark added that in extreme circumstances, post boxes could be closed and services withdrawn.
Resident Larry Jones, who has found needles on the street near his home, said: "Drug users put the needles anywhere - they aren't bothered where they put them."