Last year the World Health Organization (WHO) warned against using electronic cigarettes, saying there was no evidence to prove they were safe or helped smokers break the habit.
世界卫生组织(WHO)曾在去年提醒人们不要吸电子香烟，称没有证据证明其安全性，以及帮助戒烟的功用。
Manufacturers claim that electronic cigarettes are a safe alternative to conventional cigarettes.
制造商声称电子香烟是一种安全的香烟替代品。
Electronic cigarettes - a safe way to light up?
电子香烟——安全的吸烟方式？
"As a result, some people believe that e-cigarettes are a safe substitute for conventional cigarettes," said Prue Talbot, the director of UC Riverside's Stem Cell Center, whose lab led the research.
加利佛尼亚大学干细胞研究中心主管，他的实验室正在进行此项研究。他说：“正因为如此，许多人认为电子烟是安全的，完全可以替代传统香烟。”
"As a result, some people believe that e-cigarettes are a safe substitute for conventional cigarettes," said Prue Talbot, the director of UC Riverside's Stem Cell Center, whose lab led the research.
加利佛尼亚大学干细胞研究中心主管，他的实验室正在进行此项研究。他说：“正因为如此，许多人认为电子烟是安全的，完全可以替代传统香烟。”
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