There was little doubting what was on offer yesterday at several of the "health studios" advertised in Dublin magazine, the successor to the banned In Dublin.

In one Dorset Street "health studio" advertised in Dublin, £65 was the asking price for "everything inclusive". A young woman outlined the package as including a "full shower, sauna, massage, and the rest".

The phoneline at another "studio" was manned by a woman with an eastern European accent. When asked what was on offer, she said for £60 she would spend half an hour with a customer. "My aim is to make you happy." When asked where her "studio" was, she passed the call to another woman with a more businesslike tone who gave directions to an apartment block and said "two girls" were available. Forty-five minutes would cost £80, an hour £100.

Another health studio offered a "call-out" service only. A woman with a south Dublin accent said a "fully inclusive service was on offer". When asked about the price of the service, the woman asked at what location the service was required. She then offered to send someone out: "£120 for half-an-hour, £160 for an hour". When pressed further on what a "fully inclusive service" involved, she replied; "I'm sure you know what that involves, sir."

More than 10 studios advertised in Dublin were seeking staff. One sought a "receptionist/manageress". The advert insisted that "motivated professional people need only apply". Others sought "sophisticated glamorous ladies", "well-groomed ladies" and "friendly, outgoing staff".

There were over 40 advertisements in yesterday's issue of Dublin for "health studios" and "clubs". Some printed their addresses, others operated from mobile phone numbers. Ms Mary Fleet, of the Rothuma Women's Project, which works with prostitutes, said many of the women the project had assisted are working in what are described as "health studios".

She said women working in such "studios" were no safer than women offering sex on the streets. "Some women say they feel less secure and have less control over the number and type of clients." The Eastern Health Board Women's Health Project estimates there are as many as 600 women working in prostitution in its area and as many as 200 drug-users may be engaged in prostitution to support their or their partners' habits.

Asked what the Garda understanding of the word "health studio" was, a Garda spokesman said any suggestion of any illegality at such establishments would be investigated. It would be open to gardai to mount a surveillance operation to establish who was "coming and going" from "studios" and they could also obtain search warrants if necessary. Several brothel-owners had been prosecuted recently and their establishments closed down, he said.

A recent Criminal Assets Bureau (CAB) tax assessment shows how lucrative the brothel business can be. Mr Thomas McDonnell, from Cooraclare, Co Clare, was estimated by the bureau to have made £5,000 a week from the business with an average of 12 prostitutes a day working for him. The CAB succeeded in having a £1.75 million tax ruling made against him in February.

Gardai identified four Dublin premises, which allegedly were run by Mr McDonnell. They believed that two of those premises were owned by Mr McDonnell. The services were advertised in In Dublin.

In Dublin advertisements also made the news in July last year when it emerged that the Irish pimp who employed a murdered prostitute, Ms Belinda Pereira, advertised the services of his prostitutes in the magazine. The magazine was also mentioned during a court hearing on the case of a Kildare man who assaulted a £150-per-hour "escort girl" in 1996. The man had met the middle-class and "cultured" housewife at the Gentleman's Club escort agency after responding to an In Dublin advert.