Together we will beat cancer


E-cigarettes are in the news again. This time with headlines that they may cause cancer.

But the study that the stories are based on, published in the journal PNAS, doesn’t show this.

What did the study do?

Researchers from New York University School of Medicine looked at how e-cigarette vapour affected the DNA of mice, and human cells in a dish.

They didn’t look at how it affected people. And they didn’t directly compare it to smoking.

The researchers focused on how components of e-cig vapour damage cells’ DNA. And DNA damage increases the risk of cancer.

But they didn’t look directly at whether e-cigs caused cancer, either in mice or in people.

What did the study show?

They found that e-cig vapour raised levels of DNA damage in the lungs, bladders and hearts of mice.

They also found that the molecular machinery cells use to repair this DNA damage was less effective in the lungs of mice exposed to e-cig vapour.

Then they looked at how nicotine, the chemical that e-cigs vaporise, affects human lung and bladder cells grown in a lab dish. Nicotine is what makes cigarettes addictive, but isn’t what causes the damage from smoking. Both e-cigarettes and conventional cigarettes contain nicotine, but e-cigs have much lower levels of the harmful components of tobacco smoke.

The researchers found that nicotine damages the DNA inside those lab-grown human lung and bladder cells. And they found that these cells were less able to repair this damage. These cells were then more susceptible to further genetic faults that could give them properties like those of cancer cells.

What do the results mean?

The researchers described their results with an interesting line:

“It is therefore possible that e-cigarette smoke may contribute to lung and bladder cancer, as well as heart disease, in humans.”

While this is technically possible, the study didn’t look at humans, and so didn’t show any effect on the health of humans.

Different e-cigs devices deliver different amounts of vapour, and people use them in different ways. So the levels of e-cig vapour and nicotine used in the study might not match the levels that people are exposed to through normal use.

And other research didn’t show a link between nicotine products and cancer.

Finally and crucially, the study didn’t compare vaping to tobacco smoke.

What now?

The evidence so far shows that e-cigarettes are far less harmful than smoking.

And for some people they’re a helpful aide to stop smoking.

Up to two-thirds of long term smokers will die because of their addiction. E-cigarettes don’t contain tobacco, which is the biggest cause of preventable death worldwide.

E-cigs are a relatively new technology and so we can’t be certain about any long-term effects the devices might cause to health – they haven’t been around long enough for this to be completely worked out. But compared to smoking, the evidence so far shows they are less harmful.

Studies like this are important for building up the evidence around vaping, and how e-cig vapour might damage cells in controlled conditions. It’s a small piece in the puzzle, and must be viewed alongside other studies. Large, long-term studies are also needed to definitively answer health questions, because those conclusions can’t be made from lab-grown cells and mice alone.

The popularity of e-cigs continues to grow, but figures show that most people using these devices are now ex-smokers, and people mainly use them to quit smoking or cut down.

So conclusions around the health effects of vaping must be viewed alongside the damage that smoking has wreaked for decades. Only then can smokers make a call that could have a big impact on their health.


If you want to quit smoking you can find support to help you here, and find out about your local Stop Smoking Services here.


Faiz February 2, 2018

I tell you smoking is danger cause cancer but vaping is not danger because is liquid just for wrap ok

Steven February 1, 2018

Cancer research UK helped me switch to vaping in February 2017 After reading their first research paper. I was smoking for 23 years. After 7 months I stopped vaping and stopped smoking altogether. Even whilst i was vaping I felt a lot better then when i smoked tabacco products. now I am a proud non smoker.

anthonyb February 1, 2018

As Oliver on an earlier comment has already mentioned, changing of the coil in the Njoy. It was one of the first things that was picked up on the forum, no mention in the method of how often the coil was changed, or, how they detected when the coil was in need of changing.
As most if not all ecig users know, even changing a coil, at a regular timed interval, does not insure that any given coil is ok to use for that time interval. The reason being, that even two coils from the manufacturing batch, will not necessarily perform the same. One might last only a couple of days, the other a couple of weeks.
If it is the case, that these “scientists” have a coil that will last 12 weeks, then they have cracked it, as very ecig user on the planet would like to buy some please.
I would like to ask as well. How many mice actually survived the 12 week gassing from a burnt out coil ?

Sophie shimman February 1, 2018

Vaper is water. Water on your lung cause pneumonia. Pneumonia no cure??? Know ppl who just use vape instead fags. 3 ppl i know still vape 2 years on .

Fingerspete February 1, 2018

E-cig are not as taking in a thousand chemicals that are dangous nicotine is addicti9ve yes but from what I’ve read and seen no more harmful then tea or coffee

Ralph Concialdi February 1, 2018

I think big tobacco will do or say anything about vaping to be harmful or more harmful than cigarettes just to kept you hooked. Vaping got me off a very bad habit I started at age 12, I’m now 64 and have smoked all this time, what a waste of money. Tried patches and was still smoking with them, waste of money. Tobacco companies should be paying for this not ME, they got me hooked, and our own government could care less as long as they got their fair share of revenue ! Vaping got me off cigs the day I tried it. I think vaping is much safer than what the drug companies are making you take to quit, the side effects alone scare the hell out of me. Just like big oil paying for studies on global warming saying it’s not real, so will tobacco and drug companies will try to discourage vaping.

Oliver February 1, 2018

As others have stated, the study seems pretty flawed. Misusing the e-cigarettes in the study (failing to read the recommended use of the Njoy vape pen) and exposing mice to the extremes of vaping (puff regime consisting of 35-mL puff volumes of 4-s duration at 30-s intervals) stand out to me the most. Are the scientists changing the coils of the e-cigarettes? Do scientists have data on the average amount of use people are getting out of e-cigarettes to give us relevant data (because everything in large quantities is going to present some harmful side-effects)? Are scientists aware of the fact that certain compounds are harmful or even toxic to one species and go completely unnoticed by another? Hopefully this article from cancer research uk will spread so that people aren’t deterred from trying to swap from a life threatening habit to something less harmful by what consistently feels like propaganda and flawed research.

MarcK February 1, 2018

I had been a pack-a-day (20-25), full strength (16mg) smoker for 25 years. I have lost count of the number of times I tried to quit. I started vaping late Jan 2017. By mid Feb, I was down to 6 per day. By June, I had stopped the cigs completely. My sense of smell has come back. I feel and (apparently) look better. I am saving heaps of money. I don’t smell like an ashtray any more. I can no longer tolerate the taste of tobacco (the smell, I can live with).
Switching to vapes is probably the single best decision I have ever made.

Plus, it tastes nice…

John February 1, 2018

Big Tobbaco. You’re dying and us vapers are all clapping.

N woodward January 31, 2018

I have smoked for over 30 years and found it impossible to give up. I spent thousands over the years on acupuncture hypnotherapy and anything else I thought would help. Got myself a vape. Chose a day and I have not picked up a cigarette since! I do however admit to using lozenges on occasion too if the urge got too much. I promised myself I wouldnt ever smoke again. I do worry about the effects as they haven’t been around long enough for any proper analysis on their dangers BUT they can’t be any worse than smoking!

Adam Williams January 31, 2018

It’s about time these junk scientists were brought to court. If one smoker dies because they didn’t switch, then I’d have the for manslaughter! Well done CRUK for your response.

RAED January 31, 2018

I am a smoker , but I think the publication of this study is mainly intended for more advertising.

Matthew January 31, 2018

Another liberal based test that shows nothing of the effects on a living person

Spooky January 31, 2018

I’m a vaper, but I really tried to keep an open mind while reading the findings of this study. However, after reading a statement by lead-author Moon-shong Tang, I decided that it’s nothing more than junk science. Asked if smoking was still more harmful than vaping, he said “We don’t know which one is more harmful”. Really? You find some DNA damage in mice and petri dish cells after exposing them to vaporized high-nicotine e-liquid and all of a sudden they’re potentially more dangerous than those carcinogen-infested death sticks? Now I know why they didn’t compare e-cig vapor to cigarette smoke in the study.

Simon Williams January 31, 2018

I’m another who’s been able to give up a significant cigarette habit only because of vapes. Really has worked for me the past few years. Reassuring to read informed and educated analysis about the relative risks involved. Wish this level of insight was present in some of the media coverage to start with so rebuttal wasn’t needed so frequently. I hope policy decisions will be continue to be evidence led, rather than see vapes placed under increasingly onerous regulations which aren’t supported by the research.

Jason B. January 31, 2018

First off all your doing is spreading lies. These posts are completely unfounded with any clinical proof . When every study done by actual Doctors prove the complete opposite of this trash.

Kenneth Kawa January 30, 2018

Based on what I suspected which was bad research practices it prompted me to research this specific study a bit more in depth. So what did I find?

Quote from the Study: “E-cigarette aerosols from NJOY top fill tanks (NJOY, Inc.) filled with 1.6 mL of e-juice with 10 mg/mL nicotine in a propylene glycol/vegetable glycerin mixture (50/50 by volume; MtBakerVapor MESA). Each day the tanks were filled with fresh e-juice from a stock mixture, and the voltage was adjusted to produce a consistent wattage (∼1.96 A at 4.2 V) for each tank.”

They tested the atomizers at 4.2 volts.

I decided to go to the Njoy website to research further and found This:

Relevant Text:

All NJOY Vape Pen Batteries (including the NJOY Pre-Filled Tank Battery) operate at 3.7V when fully charged.

The NJOY Vape Tank has an atomizer resistance of approximately 2.1 ohms. We do not recommend using NJOY Vape Tanks or NJOY Pre-Filled Tanks with other batteries since we have not tested those.

NJOY specifically states not to use the tanks at over 3.7v, they are specifically designed to be used at 3.7v, the tests were done at 4.2 volts, all the data and time put into this study is a complete waste.

Daniel O'Callaghan January 30, 2018

I quit smoking through vaping 3 years ago, I now run a UK based e-liquid manufacturer and have helped thousands on their journey away from tobacco, it amazes me how such powerful Newspapers can make such crazy claims, which are just untrue, what is their agenda? to sell more papers? They never attack smoking, in fact, they actively promote the tobacco companies slightly less harmful alternatives, the last time they did was last month, claiming a study done by the tobacco company themselves had said so. Thank you Cancer research for writing this, I think by pointing this out more lives can be saved, and less sensationalist newspapers will be sold!

Louise carter January 30, 2018

I quit smoking 4 years ago but have used an e-cig since then. I never thought I’d give up using the e-cig but got a terrible cough at Christmas and haven’t used it for 4 weeks now. I always used plain tobacco flavour and went from a high dose right down to low. I’m not craving it anymore but occasionally think about it when having a drink as I always used it then. It definitely got to be more of a habbit than a need for nicotine in the end. Anyway ….. 4 weeks so far. Wish me luck x