A radio advertisement where a child explains in detail how to make a pipe to smoke methamphetamine, or P, has been upheld by an advertising watchdog.

The Brothers In Arms Youth Mentoring advertisement was pulled off air when Media Works became aware of its content.

The advertisement included a child's voice explaining the steps needed to make a P pipe. A member of the public complained to the Advertising Standards Authority which has upheld the complaint, it said in a statement released today.

While the programme's intention was to recruit mentors, which could be commended, the step to step instructions on how to make a pipe from a light bulb, which was an "illegal and dangerous practice", had to be taken into consideration, the authority said in its decision.

It was also concerned that young people may have listened to the advertisement.

The minor explained how to make the pipe before an adult's voice took over.  

"If you don't mentor them, someone else will. Become a youth mentor to a child at risk today. Visit brothersinarms.org.nz."

Brothers In Arms responded to the complaint saying that the organisation's approach was unconventional "but that is precisely why we chose it and why it has proven successful".

"The ads highlighted that the issue of negative role modelling - or mentoring - is real and toxic to the young people of New Zealand."

The ad did not endorse or encourage the behaviour, but instead used facts to highlight the issue, the organisation said.

It was intended to run for only one week. The authority's decision did not say what radio station it was aired on or for how many days it was played.

In another decision released today, the authority upheld a complaint about a prominent billboard advertisement from Spookers, a scary theme attraction based in South Auckland.

The billboard featured two ghoulish monsters covered in blood and baring their teeth aggressively. Because it was placed in a high traffic area it was likely to have been seen and frightened children, who were not Spooker's target market, the authority said.

- © Fairfax NZ News