Racy ads for a new exhibition on sexuality at Vancouver's Science World are creating controversy, with two of them even banned from bus stops.

The advertisements are for the exhibit The Science of Sexuality, geared toward youth aged 12 and up.

One ad shows a man lying in bed on top of a woman who has both legs in casts up to her knees. The caption reads: "Orgasms can kill pain."

Another shows several used tissues with the caption "Ejaculation fights colds."

"At the end of the day, it's just used tissue that we're showing," said Justin Li, a copywriter for Rethink, the agency behind the ads.

"If that kind of prompts a youngster to ask their parents about it then we say, ‘What better place to answer that question than at Science World?’"

Science World president Bryan Tisdall admits the ads may be racy, but he said that's to attract teens to the educational exhibit.

"[It’s] a responsible, factual, informative and entertaining presentation of the science of sexuality," Tisdall said.

The ads are running in local newspapers and on bus stands.

The exhibit runs until Sept. 2.