More evidence from California that kids are rapidly taking up ecigs, with faster market penetration among younger kids

On December 18, 2014, the California Department of Education reported that e-cigarettes were being adopted much faster than conventional cigarettes among California youth.  These data, collected from over 450,000 youth during the 2013-4 school year showed that 3.9 times as many 7th graders were using e-cigarettes than conventional cigarettes, 2.3 times as many 9th graders, 1.7 times as many 12th graders, and about the same rate (1.1 times) for nontradtional (continuation, community day, and other alternative school types) students.
 
These data add to the case that the e-cigarette epidemic is growing from the bottom up and that estimates of use based on adult surveys will dramatically understate the long term impact in terms of spreading nicotine addiction.
 
The is no doubt that some of these e-cigarette using kids would have or are smoking cigarettes, but it is very hard to believe that these huge increases in youth use are simply displaced cigarette smokers.