A new Canadian study is providing evidence to support fears that the highly infectious and potentially fatal hepatitis C virus can be passed among crack cocaine smokers sharing their pipes.

"We have some initial evidence that a hepatitis C infected crack smoker can, under certain circumstances, pass on the virus onto the pipe," said Dr. Benedikt Fischer, leader of a study released Wednesday.

The director of the University of Victoria's Centre for Addictions Research said the study affirms that oral crack users can pass on hepatitis C through risky crack use methods. "[That's] one of several steps necessary to transmit hepatitis C from one crack smoker to another, by way of crack-pipe sharing," he said.

The evidence comes from a new biological study of drug paraphernalia used by more than 50 inner city crack users in Toronto last year.

In the study, crack pipes were collected shortly after being used by 51 people, who were tested for hepatitis C virus antibodies. The virus was detected on one of 22 pipes tested whose owners had tested antibody positive.

The study comes as public heat over the distribution of free, safe crack-pipe kits continues to inflame some Canadian communities. Political pressure at the municipal level saw Ottawa scrap its safe pipe program earlier this year, while a similar program in Nanaimo, B.C., was put on hold.

Fischer said he felt the study's results have implications and lessons for both scientists and public health officials. "Primarily, that in order to prevent the spread of hepatitis C in the high-risk population of street drug users, you need to not only focus on injection drug users but also on crack smokers," he explained.

The results are being welcomed by some at the leading edge of drug-intervention programs. British Columbia's provincial health officer said evidence of the virus on the stems of crack pipes clearly helps the argument that hepatitis C can be transmitted between smokers of the concentrated cocaine concoction, sometimes known on the street as "rock."

"This study adds further support for interventions that are aimed at trying to reduce the spread of infectious agents between crack users," said Dr. Perry Kendall. "For quite some time we've been concerned about the potential spread of diseases like HIV, hepatitis C, tuberculosis and even syphilis, using shared crack pipes — a bit like using shared drug-injection equipment can spread diseases.

Experts have concluded that more street-level drug users in Canada are infected by hepatitis C than HIV. It's estimated that the consequences resulting from increased infection now cost Canadians $500 million to $1 billion each year.