Chemical flavourings found in e-cigarettes linked to lung disease

Harvard University scientists are calling for “urgent action” after their federally funded study confirmed dangerous, lung-destroying chemicals are commonly found in the liquids used in electronic cigarettes and other vaping devices.

The study comes in the wake of a Milwaukee Journal Sentinel investigation in October that found high levels of diacetyl and a related chemical in locally made e-liquids and exposed inadequate testing that results in manufacturers claiming their products are diacetyl-free when sometimes they are not.

The Harvard study, which focused on the presence of diacetyl in e-cigarettes, is similar to one done a year ago by a Greek researcher. But it could have more impact, because it was funded by a division of the National Institutes of Health and comes as the US government weighs whether to regulate the increasingly popular products.

Harvard researchers found diacetyl in 39 of 51 samples tested, including menthol and other flavours not typically associated with the creamy, butter flavour for which diacetyl is known. The evaluation included all the flavours from three large cigarette companies, as well as selections from e-cigarette distributors and e-liquids in disposable cartridges.

The study also noted that two other flavouring chemicals — 2,3-pentanedione and acetoin — were prevalent in the samples. Studies have found 2,3-pentanedione, the chemical cousin of diacetyl, to be equally toxic when inhaled.

The chemicals destroy the lungs’ tiniest airways, leading to scar tissue build-up that blocks airflow. It can result in a permanent, sometimes fatal, lung condition known as bronchiolitis obliterans, perhaps best known for its links to injuries and deaths in microwave popcorn workers.

“Due to the associations between diacetyl, bronchiolitis obliterans and other severe respiratory diseases observed in workers, urgent action is recommended to further evaluate this potentially widespread exposure via flavoured e-cigarettes,” said the authors of the study, published this week in the journal Environmental Health Perspectives.

An earlier Journal Sentinel investigation found potentially dangerous levels of the chemical in coffee roasting facilities and exposed cases of lung disease in commercial coffee roasters and grinders. In the wake of that report, the US Centres for Disease Control (CDC) and Prevention posted a warning to coffee industry workers in September.

The number of young people using e-cigarettes tripled last year, according to data published in April by the US Centres for Disease Control and Prevention. Roughly 2 million high schoolers — about 13 per cent — reported they had used an e-cigarette in the last 30 days, findings from the 2014 National Youth Tobacco Survey show.

It’s the first time since 2011, when the survey started collecting data on e-cigarettes, that current use among youths has surpassed use of every other tobacco product, including conventional cigarettes, according to the CDC’s news release.

There are no requirements that manufacturers test their e-liquids, nor are there any standards to meet. What testing is done is driven largely by the desire of e-liquid makers to market the safety of their products.

Many vapers have turned to e-cigarettes to aid in their effort to stop smoking conventional ones, with nicotine a common ingredient in the products.

In October, several cases of lung problems tied to e-cigarette use emerged, including a 60-year-old Vermont man who suffered an acute lung injury and was diagnosed with hypersensitivity pneumonitis after vaping “red hot cinnamon” flavoured e-cigarettes. That case was documented in the journal CHEST.

Joseph G. Allen, the lead author of the Harvard study, stressed the importance of including flavours in the discussion surrounding potential risks and hazards of vaping. People using e-cigarettes as well as physicians need to be aware of diacetyl’s ties to serious lung disease, he said.

“It’s prudent that we act soon to regulate these e-cigarettes,” said Allen, assistant professor at Harvard T.H. Chan School of Public Health. “[People] don’t know the risks associated with inhaling these chemicals. … We need to move more quickly.”

Following a failed attempt in 2009, the US Food and Drug Administration (FDA) last year proposed new rules to regulate e-cigarettes. The rule-making process allows for stakeholders, including the public, to weigh in. The comment period ended in August 2014. Regulators received 135,000 remarks and are still sifting through them more than a year later.

Asked Wednesday about the results of the new study, an FDA spokesman said it provides more information on “the important questions being raised about the ingredients in e-cigarettes”.

“The FDA values research being conducted to help inform the agency on how best to protect the public, especially youth, from the death and disease caused by tobacco use,” said spokesman Michael Felberbaum. “The agency evaluates studies as part of a larger body of evidence aimed at assisting in our mission to protect public health and furthering our understanding on particular issues.”