"Conclusions. DA and AP were found in a large proportion of sweet-flavored EC liquids, at levels that were higher than the strictest safety limits but significantly lower compared to smoking."
http://gfn.net.co/downloads/2014/posters/122 Farsalinos - DA_AP.pdf
http://gfn.net.co/downloads/2014/posters/122 Farsalinos - DA_AP.pdf