It's likely young people don't realise how much nicotine they are vaping

The Life Education Trust says some will suck in as much nicotine in a day as smoking a pack-and-a-half of cigarettes.

A survey by the Asthma and Respiratory Foundation and the Secondary Principal's Association found 27 percent of young people had vaped in the preceding seven days.

Foundation Chief Executive Letitia Harding says nicotine dependency can be disruptive for schools.

She says it can cause issues with attention and irritability -- with a dependency causing students to get out of class to go and vape in the toilets.