Democratic state senator Mark Leno is to be commended for trying to sustain California's leading position in protecting young people from the harmful effects of tobacco and nicotine, in all its forms (see Nature 523, 267; 2015). Contrary to industry claims, the use of electronic cigarettes is increasing among young people who have never smoked before (R. E. Bunnell et al. Nicotine Tob. Res. 17, 228–35; 2015), and not just among adult smokers searching for a less harmful alternative to cigarettes.

Some e-cigarettes are designed to look like cigarettes, come in flavours that appeal to children and adolescents, and are promoted and sold in shops and pharmacies that are frequented by young people. Electronic cigarettes also deliver addictive nicotine; more research is needed on the safety of their other ingredients.

Until more is known about these largely unregulated products, legislation similar to the bill that failed in California should be widely introduced to keep e-cigarettes and other electronic nicotine-delivery devices out of the hands of young people.