Found In E Cigarettes
E-cigarettes are a popular alternative to smoking, but we still know very little about the effects of them on our health. While numerous studies have explored the effect of e-cigarettes on our lungs, heart, and overall health, one important and often overlooked consideration is what effect they have on our microbiome. But a recent study has found e-cigarettes change the bacteria in our mouths. These bacterial changes can lead to disease, if left unchecked.
E-cigarettes are devices that heat a liquid into an aerosol that the user inhales. The liquid usually has nicotine and flavoring in it, and other additives. The nicotine in e-cigarettes and regular cigarettes is addictive. E-cigarettes are considered tobacco products because most of them contain nicotine, which comes from tobacco. Nicotine is highly addictive and found in most e-cigarettes. Both tobacco products and e-cigarettes pose risks to health and the safest approach is not to consume either. It is of particular public health concern that increasingly children and adolescents take up the use of e-cigarettes in some countries. Most ENDS can be manipulated by the user.
Our microbiome is the living community of bacteria, fungi, and viruses that keep us healthy. We often hear a lot about our gut microbiome, but our oral microbiome is probably just as important to our overall health. It’s the second and most diverse microbiota next to the gut, home to over 1,000 species of microbes. It’s the gateway to the rest of our digestive system and plays a key role in helping us break down foods.
Our oral microbiome also wards off potentially harmful microbes by preventing them from reproducing. A healthy oral microbiome reduces the chances of developing infections or disease.
A recent study investigating the effect of e-cigarettes on our oral microbiome found that e-cigarettes have a negative impact on the diversity of the bacteria present. They also cause an immune response from cells, which can lead to long-term damage to the surrounding cells.
Our oral microbes are not only the first to experience e-cigarette vapour, they’re also exposed to higher concentrations of the chemicals. This arguably makes them most likely of any of the body’s microbes to experience the negative effects of e-cigarettes. Changes in the balance of our mouth microbes can lead to some severe diseases, such as tooth decay and gum disease, or leave us susceptible to infections from localised gum disease that can trigger heart disease or respiratory infections or systemic infections like sepsis, which can be fatal. Some of these infections and diseases have also been associated with oral cancers.
For this particular study, 123 participants were recruited and split into five groups: smokers, non-smokers, e-cigarette users, former smokers currently using e-cigarettes, and those that use both. The team collected dental plaque samples to find out more about the microbes present and the genes they have, as well as fluid from the gums to know how the human body has reacted to these microbes. They also grew bacteria in the lab after exposing them to cigarette smoke and e-cigarette vapour.
Bacteria changes
The study found that those who used e-cigarettes had very similar species of microbes, suggesting e-cigarettes played a role in how the microbial community forms and exists. However, there were some significant differences in the smokers group, non-smoker group and e-cigarette groups, all of which had unique oral microbiomes.
When they looked at groups of people that switched from smoking to e-cigarettes and former smokers, they found their microbiota to be very similar – but they were still very different compared to non-smokers. Although this study didn’t specify which bacterial species were affected, even small changes from the healthy bacteria would likely result in negative effects overall. Gram negative bacteria, which are typically considered the “bad microbes”, were common between smokers and e-cigarette users.
This was also the case when the team did lab studies to see what effects e-cigarette vapour and cigarette smoke had on how bacteria grow. They found that the e-cigarette vapour (with or without nicotine) was able to change the way the bacteria grow, by increasing volume and the area covered by the bacteria, which can lead to infections if untreated.
The researchers also found that the microbes in the e-cigarette group had genes that lead to biofilm growth (such as dental plaque). Biofilms make microbes more resilient to the effects of drugs, toxic compounds and the immune system. This suggests that e-cigarettes vapours cause a stress response in the mouth’s microbes.
When stressed, microbes switch on their fight-or-flight genes, making them better able to survive in harsh environments. They do this by producing special enzymes that cause damage to other cells in order for the microbes to use their nutrients and get more space to reproduce. This leads to a cycle of more inflammation, causing a stronger stress response from other cells. However, if we can’t remove these stressed microbes, this sustained, long-term inflammation can lead to severe diseases.
It was also found that when e-cigarette users were compared with non-smokers, e-cigarette users had significantly higher levels of immune cell response chemicals than non-smokers. E-cigarettes users also had lower levels of chemicals that stop this stress response happening. This shows that the body is trying to fight off microbes present, much more so than in non-smokers.
The presence of a diverse microbiota is essential for healthy mouths, healthy bodies, and healthy people. But based on this study’s findings, the use of e-cigarettes has a negative impact on not only the number and types of oral microbes, but on how the microbes behave and how our body responds. Other studies have had similar findings. Though more research into the health effects of e-cigarettes is needed, current evidence suggests ditching them may be best for our overall health.
February 21, 2018
Potentially dangerous levels of metals leak from some e-cigarette heating coils
Significant amounts of toxic metals, including lead, leak from some e-cigarette heating coils and are present in the aerosols inhaled by users, according to a study from scientists at Johns Hopkins Bloomberg School of Public Health.
In the study, published online in Environmental Health Perspectives on February 21, the scientists examined e-cigarette devices owned by a sample of 56 users. They found that significant numbers of the devices generated aerosols with potentially unsafe levels of lead, chromium, manganese and/or nickel. Chronic inhalation of these metals has been linked to lung, liver, immune, cardiovascular and brain damage, and even cancers.
The Food and Drug Administration has the authority to regulate e-cigarettes but is still considering how to do so. The finding that e-cigarettes expose users—known as vapers—to what may be harmful levels of toxic metals could make this issue a focus of future FDA rules.
“It’s important for the FDA, the e-cigarette companies and vapers themselves to know that these heating coils, as currently made, seem to be leaking toxic metals—which then get into the aerosols that vapers inhale,” says study senior author Ana María Rule, PhD, MHS, an assistant scientist in the Bloomberg School’s Department of Environmental Health and Engineering.
E-cigarettes typically use a battery-supplied electric current that passes through a metal coil to heat nicotine-containing “e-liquids,” creating an aerosol—a mix including vaporized e-liquid and tiny liquid droplets. Vaping, the practice of inhaling this aerosol as if it were cigarette smoke, is now popular especially among teens, young adults and former smokers. A 2017 survey of 8th-, 10th- and 12th-grade students in public and private schools, sponsored by the National Institute on Drug Abuse, found that about one in six had used e-cigarettes in the previous 30 days.
Vaping is popular in part because it provides the nicotine “hit” and the look and feel of tobacco-smoking but without smoking’s extreme health risks. Evidence that vaping isn’t entirely safe continues to accumulate, however. Recent studies have found that e-cigarette liquids contain flavorings and other chemicals that harm cells in standard toxicology tests. Other studies, including one last year from Rule’s group, have detected significant levels of toxic metals in e-liquids exposed to the e-cigarette heating coil.
For the new study, Rule and her colleagues, including lead author Pablo Olmedo, PhD, who was a postdoctoral researcher at the Bloomberg School at the time of his work on the study, recruited 56 daily e-cigarette users from vaping conventions and e-cigarette shops around Baltimore during the fall of 2015. Working with participants’ devices, which they brought to the researchers’ lab at the Bloomberg School, the scientists tested for the presence of 15 metals in the e-liquids in the vapers’ refilling dispensers, the e-liquids in their coil-containing e-cigarette tanks and in the generated aerosols.
Consistent with prior studies, they found minimal amounts of metals in the e-liquids within refilling dispensers, but much larger amounts of some metals in the e-liquids that had been exposed to the heating coils within e-cigarette tanks. The difference indicated that the metals almost certainly had come from the coils. Most importantly, the scientists showed that the metal contamination carried over to the aerosols produced by heating the e-liquids.
Of the metals significantly present in the aerosols, lead, chromium, nickel and manganese were the ones of most concern, as all are toxic when inhaled. The median lead concentration in the aerosols, for example, was about 15 µg/kg, or more than 25 times greater than the median level in the refill dispensers. Almost 50 percent of aerosol samples had lead concentrations higher than health-based limits defined by the Environmental Protection Agency. Similarly, median aerosol concentrations of nickel, chromium and manganese approached or exceeded safe limits.
“These were median levels only,” Rule says. “The actual levels of these metals varied greatly from sample to sample, and often were much higher than safe limits.”
E-cigarette heating coils typically are made of nickel, chromium and a few other elements, making them the most obvious sources of metal contamination, although the source of the lead remains a mystery. Precisely how metals get from the coil into the surrounding e-liquid is another mystery. “We don’t know yet whether metals are chemically leaching from the coil or vaporizing when it’s heated,” Rule says. In an earlier study of the 56 vapers, led by Angela Aherrera, MPH, a DrPH student at the Bloomberg School, the levels of nickel and chromium in urine and saliva were related to those measured in the aerosol, confirming that e-cigarette users are exposed to these metals.
Formaldehyde Found In E-cigarettes
The researchers did observe, however, that aerosol metal concentrations tended to be higher for e-cigarettes with more frequently changed coils—suggesting that fresher coils give off metals more readily.
The researchers also detected significant levels of arsenic, a metal-like element that can be highly toxic, in refill e-liquid and in the corresponding tank e-liquid and aerosol samples from 10 of the 56 vapers. How the arsenic got into these e-liquids is yet another mystery—and another potential focus for regulators.
Rule and her team are now planning further studies of vaping and metal exposures, with particular attention to their impacts on people. “We’ve established with this study that there are exposures to these metals, which is the first step, but we need also to determine the actual health effects,” she says.
“Metal Concentrations in e-Cigarette Liquid and Aerosol Samples: The Contribution of Metallic Coils” was written by Pablo Olmedo, Walter Goessler, Stefan Tanda, Maria Grau-Perez, Stephanie Jarmul, Angela Aherrera, Rui Chen, Markus Hilpert, Joanna E. Cohen, Ana Navas-Acien, and Ana M. Rule.
Support for the research was provided by the Maryland State Cigarette Restitution Fund (PHPA-G2034), the Alfonso Martín Escudero Foundation, the American Heart Association Tobacco Regulation and Addiction Center (1P50HL120163), and the National Institute of Environmental Health Sciences (5P30ES009089).
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Carcinogens Found In E-cigarettes
Media contacts: Barbara Benham at 410-614-6029 and bbenham1@jhu.edu and Nicole Hughes at 443-287-2905 and nhughes4@jhu.edu.