The shocking discovery comes in the wake of a Manchester Evening News investigation into the shady practices of hawkers working in Market Street under a loophole in the law.

Council officials have discovered that counterfeit perfume – like the one pictured right – was causing skin reactions under test conditions because "inferior or unsuitable ingredients" including urine were being used.

Town hall chiefs will now go to Parliament to demand a special law allowing them to boot rogue street traders out of the city for good.

The M.E.N. revealed in July the scale of the problem, with up to 20 hawkers working highly lucrative pitches on Market Street and outside the Manchester Evening News Arena.

We told how one perfume seller was using "bogus" customers to drum up business before he fled when we confronted him with our findings.

When we returned days later with a council-led “hit squad”, Pat Karney – a councillor with special responsibility for the city centre – described the scene as like a “Moroccan bazaar”.

Now the council has voted to ask Parliament for a new Act, which would apply only to Manchester, closing a loophole that allows people to use £12.50 pedlar’s licences to trade on the streets. Pedlars are supposed to move from city to city – but council CCTV operators have been spending huge amounts of time gathering evidence that most pedlars flout the law by simply staying in one place.

The new Act, which is due to be presented to the House of Commons next month, would mean pedlars could only operate door-to-door and it would give officials the power to seize goods from those who did not comply.

The council’s Neil Swannick  said: “Illegal pedlars cause real problems on the streets of Manchester, selling often sub-standard goods which put members of the public at risk, undermining legitimate traders and causing obstructions.

“We are determined to protect the quality of the city centre and of the goods which customers buy, and to do that we need extra powers.”

Town hall chiefs are exercising a right to approach Parliament for “location specific” laws if they feel their powers are not strong enough to tackle particular issues. Newcastle, Westminster and Liverpool are among seven councils who have already got similar local acts passed to tackle street traders.

The move was so successful in Medway, in the south east, that neighbouring Maidstone sought and got a similar law because the problem simply migrated over the border.

James Allen, director of events at the M.E.N. Arena, said pedlars often behaved “in a threatening and intimidating way” and sold sub-standard goods.

Coun Karney said: “People will rightly be horrified to hear of this. It is precisely for this kind of reason that we are taking action. “We will do what we need to do to protect the people of Manchester and clean these rogues from our streets.”