Since their first appearance more than a decade ago, people have generally assumed that they are a safer alternative to cigarettes because smokers are not inhaling known carcinogens. But new evidence keeps emerging that e-cigarettes are not as safe as their manufacturers and advertisers would like us to believe.
Researchers analyzing the contents of e-cigarettes are finding that they may be as risky as tobacco. For instance, tobacco is known to significantly impair the immune response of cells in the respiratory system. To find out the effect of e-cigarettes on the immune system, specifically the expression of nearly 600 genes involved in immune response, researchers obtained tissue samples from the epithelial layer inside the nasal cavities of smokers, non-smokers and e-cigarette users.
In conventional cigarette smokers, they observed signs that a number of key immune genes in the nasal mucosa were suppressed. In e-cigarette users, they found the same genetic changes, as well as suppression of additional immune genes. The findings imply that e-cigarettes have an even broader effect on the respiratory mucosal immune response system than conventional cigarettes.
A new study also shows that many of the flavorings used in e-cigarettes are equally harmful to users. Though some of these flavorings are approved for oral consumption by the US Food and Drug Administration (FDA), researchers point out that this does not mean they are safe for inhalation.
The digestive systems and respiratory systems are very different. Our stomachs are full of acids and enzymes that break down food and deal with chemicals; this environment is very different than our respiratory systems, say the team behind the study.
Studying the effects on smokers of cinnamaldehyde, the chemical that gives cinnamon flavor to e-cigarettes, researchers found it to induce a chain of cellular mechanisms that potentially led to impairing immune response in lungs.
The World Health Organization (WHO), points out that tobacco kills around six million people each year. More than five million of those deaths are the result of direct tobacco use while more than 600 000 are the result of non-smokers being exposed to second-hand smoke.
Moreover, with nearly 80 percent of the world's 1 billion smokers living in low- and middle-income countries, and tobacco killing up to half of its users, it has a significant impact on the economy of these countries.