Toronto, Dec 17 (IANS): Teenagers who smoke contraband or illegally procured cigarettes are more likely to use illicit drugs, shows a study.

"The rate of illicit drug use among the contraband smokers is higher than that among teenagers who smoke non-contraband cigarettes - sometimes double or triple the rate," said Mesbah Sharaf, health economics lecturer at the University of Alberta in Canada.

For the study, the researchers used a national sample of 2,136 current smoker students in grades nine to 12 from the 2010-2011 Youth Smoking Survey conducted by Statistics Canada.

The researchers found that 22 percent of all adolescent smokers in Canada used cocaine. Among those who smoked contraband cigarettes, 31 percent reported using cocaine, whereas only 18 percent of non-contraband smokers reported using cocaine.

Use of MDMA (ecstasy) was also more prevalent among contraband smokers (45 percent) than among non-contraband smokers (33 percent).

The rate of ketamine and amphetamine use among the contraband-smoking teenagers was almost three times as high as the rate among non-contraband-using teenagers - and more than six times as high for heroin.

"If, as we believe this study shows, contraband cigarette use is associated with illicit drug use, then intensive effort needs to be made to avoid this - by both government and tobacco companies," Sharaf said.

The study appeared in The Journal of Primary Prevention.