WASHINGTON (Xinhua) -- The US Food and Drug Administration (FDA) on Wednesday announced that a laboratory analysis has found electronic cigarette contain carcinogens and toxic chemicals such as diethylene glycol, an ingredient used in antifreeze. 

Electronic cigarettes, also called "e-cigarettes," are battery-operated devices that generally contain cartridges filled with nicotine, flavor and other chemicals. The electronic cigarette turns nicotine, which is highly addictive, and other chemicals into a vapor that is inhaled by the user.

These products are marketed and sold to young people and are readily available online and in shopping malls. In addition, these products do not contain any health warnings comparable to FDA-approved nicotine replacement products or conventional cigarettes. They are also available in different flavors, such as chocolate and mint, which may appeal to young people. 

Public health experts expressed concern that electronic cigarettes could increase nicotine addiction and tobacco use in young people. 

"The FDA is concerned about the safety of these products and how they are marketed to the public," said Margaret A. Hamburg, commissioner of food and drugs. 

Because these products have not been submitted to the FDA for evaluation or approval, at this time the agency has no way of knowing, except for the limited testing it has performed, the levels of nicotine or the amounts or kinds of other chemicals that the various brands of these products deliver to the user. 

The FDA's Division of Pharmaceutical Analysis analyzed the ingredients in a small sample of cartridges from two leading brands of electronic cigarettes. In one sample, the FDA's analyses detected diethylene glycol, a chemical used in antifreeze that is toxic to humans, and in several other samples, the FDA analyses detected carcinogens, including nitrosamines. These tests indicate that these products contained detectable levels of known carcinogens and toxic chemicals to which users could potentially be exposed. 

The FDA has been examining and detaining shipments of e-cigarettes at the border and the products it has examined thus far meet the definition of a combination drug-device product under the Federal Food, Drug, and Cosmetic Act. 

The FDA has been challenged regarding its jurisdiction over certain e-cigarettes in a case currently pending in federal district court. The agency is also planning additional activities to address its concerns about these products.