The smokable form of cocaine causes risky sexual behaviour among users, drug researchers have found.

And patient charts at the Island's Sexually Transmitted Diseases Clinic show a significant number of HIV-positive residents have admitted smoking crack.

The finding tallies with studies in Puerto Rico and America which show crack addicts are becoming an explosive vehicle for transmitting HIV.

Of the 189 people in Bermuda who are known to be HIV positive and the 34 who are suffering full-blown AIDS, 21 admitted to STD Clinic staff that they indulged in crack, smokable heroin and/or excessive alcohol use. Six were women and 15 were men.

But nurse epidemiologist Ms Rhonda Daniels believes the number is probably much higher.

Clinic staff have to take patients at their word, noted Ms Daniels, who works at the STD Clinic where she heads the Epidemiology/Surveillance Unit.

Patients were reluctant to admit drug use, she said.

"The use of crack and other drugs definitely plays a large part in the spread of AIDS because they lead to high-risk behaviour such as sex for drugs,'' Ms Daniels said.

"It is a concerning trend, because it is evident there is a high use of crack and (smokable) heroin in our community -- as well as alcohol.'' What was even more worrying, Ms Daniels said, was that people tended to think they were not at risk for AIDS if they were not in one of the high-risk groups: IV drug users, homosexuals/bisexuals and promiscuous heterosexuals.

The San Juan Star reported last week on a US/Puerto Rican study which found that crack addicts often engaged in unprotected sex because they were high or prostituting themselves out of desperation for more "rocks''. The drug was also found to lead to increased sexual appetite among beginning users.

Health Department officials here are becoming increasingly concerned about the connection between crack and HIV, the virus that causes AIDS.

There was also alarm over the re-emergence in Bermuda of heroin, which is even more addictive than crack.

"It's going to be a real factor soon I imagine,'' Health Minister the Hon.

Quinton Edness said. "We will be able to record incidences of people who use crack or who are prostitutes -- having AIDS. We just haven't picked up on it yet.'' There were "many terrible ways'' in which the disease could be communicated, he said.

"One of the worst ways is through prostitution by drug addicts,'' Mr. Edness said.

"That type of person loses all sense of responsibility. They are prepared to have sex with anyone and that is very dangerous. They can contaminate a host of other people. I know this is a big factor in Asia and North America.'' Those under the influence of alcohol or drugs generally had no sense of caution, he said.

"We have to try and reach people who are putting themselves in high-risk situations,'' he said.

Ms Daniels suggested no longer "denying that our teens are having sex''.

Those who injected heroin in the past and shared needles with other users currently make up the largest group of people with AIDS in Bermuda.

But people have changed their drug use habits from needles to other means, Government's Chief Medical Officer Dr. John Cann pointed out.

Although heroin abuse is on the rise in Bermuda, addicts were no longer "shooting up'' the drug, but smoking or snorting it, he said.

Dr. Cann said there was evidence some people who are HIV-positive have been selling sex for favours, including crack or cash to buy it with.

Mr. Edness said the Department was also aware of crack causing heightened sexual desire in the initial stages of use.

The Minister said AIDS risk factor statistics continue to be broken down into four categories: Intravenous drug use, Homosexuals/bisexuals, Heterosexuals and Other.

Crack use was often an added risk factor in either of the categories but there was not a separate category for it, he said.

If someone who tests positive to HIV admits smoking crack it is recorded on their chart at the STD Clinic, Ms Daniels said.

Statistics show that in January, seven people tested HIV-positive -- four got it from past IV drug use, two were homosexual or bisexual and one was heterosexual.

The San Juan Star newspaper reported that crack has been found to cause hypersexual behaviour among beginning smokers.

And those addicted to it tended to sell their bodies more cheaply and frequently than other prostitutes to obtain the drug.

"Crack users accordingly have more sexual partners and more unprotected sex than other groups,'' the article said.

Puerto Rico state epidemiologist Mr. John Rullan was quoted as saying, "There's no question crack is a new and dangerous component in the AIDS scenario.'' "We now have to look at crack with as much vigour as we have been addressing IV drug use if we are going to have an impact in stopping and preventing this disease.'' The article said a study by Puerto Rico drug researchers and the US Mental Health and Anti-addiction Services Administration (MHASA), based on data taken from a sample of 260 crack users on the island over a one-and-a-half-year period, found a 20 percent HIV infection rate among women, compared with 11 percent among men.

The same study also found a higher incidence of failure to use condoms during sex among the men and women who smoked crack -- more than half did not.

And it found that the female crack smokers were more likely to trade sex for the drug or for cash to buy it.

Some US drug researchers call it "crack specific prostitution''.

Others call it "sex slavery'', because of the compulsion to obtain more crack outweighs all other needs.

So far 247 people have acquired AIDS and 213 have died of the disease.

And 31 people tested HIV positive last year.