Mum Marie Mann said the two children, aged five and three, picked up the condoms in separate incidents in different parts of the town.

She was so concerned about the possible risk of infection that she contacted NHS Direct for advice.

Mrs Mann says both incidents happened in the past month, but she said she has seen condoms on local pavements on several other occasions and is warning other parents to be aware of the dangers.

The first incident took place in a play park off Lincoln Way, where she says her three-year-old son, Ehsan, found a condom in a while he was playing in a play park in Lincoln Way.

Then last week, his older brother, five-year-old Javid, picked up another condom which was lying on the pavement in Coltman Avenue, near their home in Schofield Avenue.

“We were just walking along the road with my five year old behind us when he said: ‘Look mum’ - he had the condom in both hands and was playing with it.

“Obviously he had no idea what he had picked up.

“I have since explained to him what they are because I have seen so many of them on the footpaths, sometimes used and sometimes not,” she said.

“It is so disgusting that we feel parents need some awareness because these are not isolated incidents.”

Mrs Mann was so horrified by the most recent incident, in which the condom had apparently been used, that she immediately wiped her son with anti-bacterial mousse and contacted NHS Direct for advice.

She was assured that in this case the risk of infection was minimal but fears that the situation could have been very serious and is warning other parents of the dangers.

“We have lived in Beverley for three and a half years.

“Before that we lived in Hull and I don’t recall coming across anything like this in Hull,” she said.

“The thought that horrifies me is that if a child was on its own, perhaps walking to school, they would not know what they are dealing with. I think it is just horrible.”