The National Park Service toughened smoking prohibitions in its national parks by including electronic smoking devices.

Vapor exhaled from electronic cigarettes and other electronic nicotine delivery systems (ENDS) contains nicotine at a level roughly one-tenth of that found in second-hand smoke, the park service said. Nicotine is highly addictive, toxic to developing fetuses, and impairs fetal brain and lung development. Recent public health studies suggest that ENDS aerosols can also contain heavy metals, ultrafine particulates, and cancer-causing agents.

“Protecting the health and safety of our visitors and employees is one of the most critical duties of the National Park Service,” NPS Director Jonathan B. Jarvis said in issuing the policy memorandum.

Multi-race individuals (26.8 percent), followed by Native Americans (26.1 percent), have the highest percentage of adult smokers, as assessed by race, according to a survey by the Centers for Disease Control and Prevention.

The park service now bans ENDS use and tobacco smoking inside all NPS-owned, -leased or -administered buildings; within 25 feet of any entrance or exit; within any type of government-owned or –leased vehicles, and any area facility the site manager deems necessary to protect park resources, reduce fire risk, protect employees and the public from vapors or tobacco smoke or prevent conflicts among employees or visitors.

The policy memorandum establishes National Park Service guidance on the use of ENDS and is effective immediately. Under this guidance, the use of ENDS will not be allowed within all facilities and vehicles that are Government owned or leased, and within all national park concessions facilities.

E-cigarettes are estimated to be a $1.5 billion industry, according to Fortune magazine, with sales predicted to rise by 24 percent through 2018. Some states are considering taxing the devices.

The National Park Service issued its initial tobacco smoking prohibitions in June, 2009.