“E-cigarettes are not as harmful as conventional cigarettes – but e-cigarettes are not harmless. They do contain nicotine, which is a highly addictive neurotoxin,” according to California’s health officer Dr. Ron Chapman. While traditional paper cigarettes burn tobacco leaves, releasing tar and carcinogenic chemicals, electronic cigarettes heat liquid nicotine derived from tobacco into an inhalable vapor. Electronic cigarettes emit at least 10 chemicals known to cause cancer or birth defects, including formaldehyde, lead and nickel. The public should know about the dangers of e-cigarettes, he warned.