OAL team works on analysis of biomass-burning emissions

OAL team works on analysis of biomass-burning emissions

Emissions from wildland fires and biomass fuel use contribute to regional air pollution events, global scale radiative forcing and climate change, and cause severe health effects. However, the role of organic compounds in these processes is still largely unknown and underestimated.

For this reason, the OAL team performs combustion experiments in the DRI’s combustion chamber to characterize in details chemical and physical properties of biomass-burning emissions, especially organic compounds.

Moreover, to study atmospheric aging of combustion pollutants, OAL students operate the oxidation the flow reactor (OFR) that needs only 1-2 minutes to mimic 7 days of oxidation in real atmospheric conditions.

This work is supported by NSF (grant no. AGS-1544425, P.I.: V. Samburova, co-PIs: H. Moosmüller and A. Khlystov), NASA (grant no. NNX15AI48G, P.I.: H. Moosmüller, co-P.I.: V. Samburova), and DRI’s Wildland Fire Science Center (WFSC)

Gallery:

Malaysian peat fuel is prepared for combustion experiment

The OAL team use Malaysian peat fuel for a combustion experiment.

Students Chiranjivi Bhattarai, Michaelene (Miki) Iaukea-Lum, and Deep Sengupta preparing eucalyptus for burning experiment in the DRI’s combustion chamber.

Students Chiranjivi Bhattarai, Michaelene (Miki) Iaukea-Lum, and Deep Sengupta preparing eucalyptus for burning experiment in the DRI’s combustion chamber.

TIGF filters sampled with biomass-burning emissions from combustion of Malaysian peat.

TIGF filters sampled with biomass-burning emissions from combustion of Malaysian peat.

OAL’s oxidation flow reactor

OAL’s oxidation flow reactor

OAL “biomass-burning” team

OAL “biomass-burning” team

OAL Assistant Research Professor Vera Samburova is starting the combustion experiment with Malaysian peat fuel.

OAL Assistant Research Professor Vera Samburova is starting the combustion experiment with Malaysian peat fuel.

OAL team at the 80th Nevada State Legislature!

OAL team at the 80th Nevada State Legislature!

Drs. Andrey Khlystov and Vera Samburova participated in the DRI Day at the NV Legislature today. They met with Senator Heidi Gansert, Assemblywomen Heidi Ann Swank and Lisa Krasner, and educated many members of NV State Legislature on dangers of flavoring compounds in e-cigarettes. Dr. Khlystov attended the recognition of DRI from the floor of the NV Senate by the State Senator Heidi Gansert.

OAL team attends SRNT Annual Meeting, February 20-23, 2019

OAL team attends SRNT Annual Meeting, February 20-23, 2019

The Organic Analytical Lab was well represented at the Society for Research on Nicotine and Tobacco 2019 Annual Meeting in San Francisco. Drs. Andrey Khlystov, Vera Samburova and Yeongkwon Son attended the meeting and Yeong presented three (!!!) posters. Please visit https://cdn.ymaws.com/www.srnt.org/resource/resmgr/SRNT19_Abstracts.pdf to see the abstracts (POS2-8, POS2-17 and POS4-47). The posters generated a lot of interest and created new opportunities for collaboration with governmental agencies and educational institutions.

New Teaching Assistants at UNR Physics: Chiranjivi and Deep

New Teaching Assistants at UNR Physics: Chiranjivi and Deep

OAL graduate students, Deep Sengupta and Chiranjivi Bhattarai have been selected to become Teaching Assistants in UNR Physics for Scientists and Engineers courses! Deep is a TA for three different groups taking course PHYS 181L; Chiranjivi is a TA in PHYS 180L and PHYS 180 recitation. Congratulations and good luck, Chiranjivi and Deep!

OAL members present at the NPHA annual meeting

OAL members present at the NPHA annual meeting

OAL scientists Drs. Vera Samburova and Yeongkwon Son attended the 2018 Nevada Public Health Association annual conference in Las Vegas. They gave presentations on potential hazards of e-cigarette use to the broad audience of health care providers, clinicians, educators, and researchers. The talks generated a lot of interest among the attendees and initiated productive discussions. Well done, Yeong and Vera!

OAL Director gives a keynote speech at the ICAST, September 14-15, 2018

OAL Director gives a keynote speech at the ICAST, September 14-15, 2018

Dr. Andrey Khlystov was invited to give a keynote speech at the 25th International Conference on Aerosol Science and Technology (ICAST) in Tainan, Taiwan. His presentation “Light-absorbing organic carbon in biomass burning aerosols, its properties and transformation” highlighted NSF-sponsored research done at the OAL.

OAL students at the IAC 2018, September 2-7, 2018

OAL students at the IAC 2018, September 2-7, 2018

Deep Sengupta presented a poster “Semi-Volatile Organic Compounds in Fresh and Laboratory-Aged Biomass Burning Aerosols” and gave a talk “Estimation of Snow Albedo Reduction due to Deposition of Light Absorbing Aerosols Using a Monte Carlo Radiative Transfer Model” at the 10th International Aerosol Conference in St.Louis, USA. Well done, Deep!!

Local media coverage of the latest OAL publication

Local media coverage of the latest OAL publication

The latest OAL publication by Vera Samburova et al. on aldehydes in exhaled breath attracted the attention of all major local media outlets! Please click “Continue reading” to see image gallery and enable links to videos.

Reno Gazette Journal (RGJ) story: https://www.rgj.com/story/news/2018/08/20/vaping-leaves-cancer-causing-chemicals-lungs-study/1015582002/ and RGJ Facebook Live: https://www.facebook.com/RGJmedia/videos/301882897057641/

RGJ reporter interviews OAL team for FB live

RGJ reporter interviews OAL team for FB live

KTVN Channel 2 news story: http://www.ktvn.com/story/38910498/pilot-study-shows-significant-amount-of-carcinogens-stay-in-lungs-after-vaping

KTVN2 reporter interviews Dr. Vera Samburova

KTVN2 reporter interviews Dr. Vera Samburova

News 4-Fox 11 story: https://mynews4.com/news/local/dri-scientists-e-cigs-leave-dangerous-amounts-of-cancer-causing-chemicals-in-lungs

Fox 11 reporter and cameraman interviews Dr. Khlystov

Fox 11 reporter and cameraman interviews Dr. Khlystov

Congratulations to Chiranjivi Bhattarai!

Congratulations to Chiranjivi Bhattarai!

Congratulations to Chiranjivi Bhattarai who successfully defended his Master of Science in Atmospheric Chemistry thesis on June 27th, 2018, at the Desert Research Institute!  Chiranjivi has joined the OAL in fall 2014, and conducted a detailed study of “Physical and Chemical Characterization of Fresh and Aged Biomass Burning Emissions” under the supervision of Dr. Andrey Khlystov. Results of this study will be published in the journal Aerosol Science and Technology, stay tuned! Update Feb 2019: the paper was published in November 2018 (AS&T vol 52 No 11) and is among the Top Ten downloaded despite its limited accessibility!

NSHE Rising Researcher Award presentation

NSHE Rising Researcher Award presentation

DRI President Dr. Kristen Averyt presented Dr. Vera Sumburova with the NSHE Rising Researcher Award during a ceremony at the DRI’s Las Vegas location on June 21, 2018.

OAL Visits the NV Dept of Health and Human Services

OAL Visits the NV Dept of Health and Human Services

A DRI team (DAS Executive Director Marc Pitchford and OAL scientists Drs. Andrey Khlystov and Vera Samburova) traveled to Carson City to meet with the officials from the Nevada Department of Health and Human Services. Dr. Khlystov presented results of OAL’s study on the hazardous levels of toxic aldehydes in e-cigarette flavorings and the new OAL’s findings on emissions from very popular JUUL e-cigarettes. While having relatively low carbon monoxide and formaldehyde emissions, JUUL pods subject users to very high concentrations of nicotine, a known addictive substance. Active discussion followed the presentation, and a visit by NV DHHS representative to DRI is expected in the near future. Nevada leads the nation in juvenile e-cigarette use, causing serious concern among state health officials. E-cigarette emissions research done by the OAL at DRI helps to educate and empower the lawmakers.

OAL Participates in Toxic Metals Monitoring Campaign

OAL Participates in Toxic Metals Monitoring Campaign

Dave Campbell, Associate Research Scientist at the DRI’s Division of Atmospheric Sciences and the Organic Analytical Lab member, participated in a 5-week long monitoring campaign near Paramount, CA, sponsored by the South Coast Air Quality Management District and conducted in collaboration with Aerodyne Research Inc.

Dave used Steam-Jet Aerosol Collector – long Pathlength Absorbance Spectroscopy (SJAC-LPAS) instrument developed by Dr. Khlystov to perform real-time on-line measurements of hexavalent chromium concentration in the air, while riding aboard Aerodyne Mobile Laboratory.

Board of Regents awards Dr. Vera Samburova 2018 Rising Researcher Award

Board of Regents awards Dr. Vera Samburova 2018 Rising Researcher Award

The Nevada System of Higher Education (NSHE) Board of Regents this week awarded Vera Samburova, Ph.D., an assistant research professor of atmospheric chemistry and air pollution at DRI, with its annual Rising Researcher Award.

She was recognized for her early-career accomplishments and leading a new and exciting area of research at DRI looking at inhalation and indoor air quality related health effects. The honor is given annually to one NSHE faculty member from DRI, UNR, and UNLV.

Reno, Nev.  (Thursday, March 1, 2018) – The Nevada System of Higher Education (NSHE) Board of Regents this week awarded Vera Samburova, Ph.D., an assistant research professor of atmospheric chemistry and air pollution at DRI, with its annual Rising Researcher Award.

She was recognized for her early-career accomplishments and leading a new and exciting area of research at DRI looking at inhalation and indoor air quality related health effects. The honor is given annually to one NSHE faculty member from DRI, UNR, and UNLV.

As a member of the DRI’s Organic Analysis Laboratory, Samburova’s research focuses on the collection and analysis of atmospheric organic species, characterization and quantification of organic emissions from various sources like biomass burning and fossil fuels.

She recently initiated an internally funded research project investigating the emissions from e-cigarettes. Her research team found that the aerosols (commonly called vapors) produced by flavored e-cigarettes liquids contain dangerous levels of hazardous chemicals known to cause cancer in humans. Their research was published in Environmental Science & Technology (ES&T), a journal of the American Chemical Society.

“The health impacts of e-cigarettes are still widely unknown and not researched,” said Samburova. “I am incredibly honored to be recognized for this important work and everything that our team at DRI has done to advance this important and emerging field of research.”

Samburova has authored a total of 35 peer-reviewed publications, 20 since joining DRI, and seven of which she was the first author. She has served as a principal investigator, and co-principal investigator, and a key personnel/scientist for 15 projects that have received over $2 million in external research funding.

She is also actively involved in the Atmospheric Sciences Graduate Program at the University of Nevada, Reno where she has taught classes every year starting in 2008 and has been the Deputy Director of that program for the last five years.

Samburova received her Ph.D. in Environmental Organic Chemistry from the Swiss Federal Institute of Technology, Zurich in 2007, after which she was recruited at Desert Research Institute as a Post Doc and subsequently transitioned to an Assistant Research Professor.

Dr. Andrey Khlystov wins Society for Research on Nicotine & Tobacco New Investigator Award

Dr. Andrey Khlystov wins Society for Research on Nicotine & Tobacco New Investigator Award

Dr. Andrey Khlystov has been named a “2018 New Investigator Award Winner for Best Abstract” by the Society for Research on Nicotine & Tobacco for his presentation “The Effect of Puff Topography and Power Settings on Aldehyde and Carbon Monoxide in E-cigarette Aerosols”. The award was presented at the Society’s annual meeting in Baltimore, MD. Dr. Khlystov is the Director of the Organic Analytical Laboratory and a Research Professor of Atmospheric Chemistry at DRI. Two other OAL members presented posters at the SRNT meeting: Dr. Vera Samburova (“Carbonyl Compounds in Exhaled E-cigarette Aerosols”) and Dr. Yeongkwon Son (“Indoor Air Quality in Electronic Cigarette Vape Shops”).

A few clarifications about our e-cigeratte study

A few clarifications about our e-cigeratte study

In the Organic Analytic Laboratory at DRI, our main specialty is sampling and detailed chemical analysis of organic air pollutants. Our team has more than 20 years of experience in this area.

E-cigarette research is new for us but involves similar sampling and analytical techniques. Having seen advertisements for e-cigarettes that claimed they are safe because liquids contain only FDA approved ingredients, we decided to apply our expertise to see what is in e-cigarette vapors. This resulted in the publication of the first set of results concerning the role of flavorings in aldehyde formation during vaping.

Following the publication of our paper, we received a lot of attention from media, the blogosphere, and individual vapers. This shows the importance of the problem and we are pleased to have made a contribution to the ongoing discussion of the pros and cons of vaping.

While the news coverage was generally accurate, we noticed some misunderstanding and misrepresentation of the study, especially in comment sections of media articles and on some blogs. For example, we were amazed to see some commenters suggesting that our study was sponsored by the tobacco industry. This is completely untrue. This was an internally funded study. None of us, nor the Desert Research Institute has any connection to the tobacco industry.

A recent blog post by Dr. Farsalinos was also brought to my attention. In his post, Dr. Farsalinos states that our “results contradict previous research on aldehyde emissions” and he makes other assertions that I would like to address here in more detail. By making this statement, Dr. Farsalinos revealed that (a) he is not up-to-date with the current literature, and (b) has not read our paper carefully, because we explicitly compare our results to other studies.

Aldehyde Concentrations

Our paper states (from the top of the right column of page four): “For example, maximal formaldehyde emissions observed in this study are approximately 2−7 times lower than the steady-state emissions measured by Sleiman et al.,9 who reported values ranging from 13000 to 48200 ng/mg. In terms of emissions per puff, our formaldehyde data [0.12−50 μg/puff (Table S3)] are comparable to values of 0.05−50 μg/puff reported by Gillman et al.6 and 30−100 μg/puff reported by Sleiman et al.9”

Yes, the highest observed concentrations in our study, which seem to have caused disbelief in some such as Dr. Farsalinos, are actually several times lower than those reported in another recent study (Sleiman et al.). In Sleiman et al., it is reported that the first few puffs significantly underestimate aldehyde emissions as the coil temperature needs time to come to steady state. Most if not all of the previous studies that reported low aldehyde concentrations did not include warm-up puffs. This is also discussed in our paper.

Flavoring Compounds

Our study also clearly states – “our results do not suggest that PG or VG produces no aldehydes, but that flavoring compounds are responsible for the main part of the emitted toxic aldehydes. Nondetects for unflavored liquids reported in this study are likely due to the small number of puffs that we have used in our measurements. By collecting more puffs per measurement, we could have quantified emissions for unflavored liquids. This quantification, however, is of minor consequence, as the flavored liquids produce significantly more aldehydes than unflavored ones do” (top of the left column on page 5).

We are not contesting the contribution of PG/VG to aldehyde formation. Our point is that flavorings cause significantly higher emissions.

The standard excuse (written about here – http://www.nejm.org/doi/full/10.1056/NEJMc1502242) of a “dry-puff” to explain aldehyde emissions cannot be applied to our study.

There is only one peer-reviewed paper that asserts that high aldehyde concentrations are due to dry puffs only and that these cause aversion in users. That paper was reviewed in just 11 days and methodological problems have been identified by other researchers – see a review by Shihadeh et al. here http://onlinelibrary.wiley.com/doi/10.1111/add.13066/full.

As was discussed above, the evidence is mounting that aldehyde levels in e-cigarette vapors could be dangerously high.

Reproducibility

While we do agree with Dr. Farsalinos that the strength of science lies in reproducibility of experimental results and we wish anyone success in reproducing our study, we strongly believe that science requires impartiality and an open mind. Statements such as “I should note that it is impossible to convincingly identify something that went wrong in this study” are derogatory and assume that our study is wrong.

We would also suggest Dr. Farsalinos reproduce studies by Sleiman et al., Gillman et al., and Jensen et al.

It should be also noted that aldehydes and their DNPH adducts are chemically unstable. Experience and utmost care are required to obtain accurate results.

While we are not interested in proving or disproving Dr. Farsalinos’ dry puff study, we have collected some preliminary data that contradicts conclusions of that study regarding high aldehyde levels causing an “unpleasant” sensation during vaping.

We are collecting data for secondary aldehyde exposure associated with vaping. To estimate secondary emissions, we collected exhaled breath from three research volunteers, who were asked to vape as they normally do in a real-life scenario. The results are shown in the unpublished graph below (DO NOT CITE).

The levels are comparable to what we have measured per puff. One volunteer produced higher concentrations because a different device was used. None of our volunteers complained about anything unpleasant during their vaping.

Drypuff

We continue working on characterizing other pollutants in e-cigarette vapors and have data collaborating the effect of flavoring additives we reported in the ES&T.

Stay tuned for more exciting results and important research findings from our team!

– Andrey Khylstov, Ph.D

A few clarifications about our e-cigeratte study

Hazardous chemicals discovered in flavored e-cigarette vapor

Scientists stress need for thorough research into flavored e-liquids

RENO – Building on more than 30 years of air quality research in some of the most polluted urban environments on Earth, a team of atmospheric scientists at the Desert Research Institute (DRI) has turned their attention toward the growing e-cigarette industry and the unidentified effects of vaping on human health.New research published today in Environmental Science & Technology (ES&T), a journal of the American Chemical Society, reports that the aerosols (commonly called vapors) produced by flavored e-cigarettes liquids contain dangerous levels of hazardous chemicals known to cause cancer in humans.

The study “Flavoring compounds dominate toxic aldehyde production during e-cigarette vaping” confirms that these toxic aldehydes, such as formaldehyde, are formed not by evaporation, but rather during the chemical breakdown of the

“How these flavoring compounds in e-cigarette liquids affect the chemical composition and toxicity of the vapor that e-cigarettes produce is practically unknown,” explained Andrey Khlystov, Ph.D., an associate research professor of atmospheric sciences at DRI. “Our results show that production of toxic aldehydes is exponentially dependent on the concentration of flavoring compounds.”

E-cigarette liquids have been marketed in nearly 8,000 different flavors, according to a 2014 report from the World Health Organization. Recent reports have shown that many flavors, such as Gummy Bear, Tutti Fruitty, Bubble Gum, etc., were found to be especially appealing to adolescents and young adults.

The U.S. Food and Drug Administration (FDA) reports that 16-percent of high school and 5.3-percent of middle school students were current users of e-cigarettes in 2015, making e-cigarettes the most commonly used tobacco product among youth for the second consecutive year. In 2014, 12.6-percent of U.S. adults had ever tried an e-cigarette and about 3.7-percent of adults used e-cigarettes daily or some days.

Khlystov and his colleagues measured concentrations of 12 aldehydes in aerosols produced by three common e-cigarette devices.

To determine whether the flavoring additives affected aldehyde production during vaping, five flavored e-liquids were tested in each device. In addition, two unflavored e-liquids were also tested.

“To determine the specific role of the flavoring compounds we fixed all important parameters that could affect aldehyde production and varied only the type and concentration of flavors,” explained Vera Samburova, Ph.D., an assistant research professor of chemistry at DRI.

Samburova added that the devices used in the study represented three of the most common types of e-cigarettes – bottom and top coil clearomizers, and a cartomizer.

The study avoided any variation in puff topography (e.g., puff volume, puff velocity, interval between puffs) by utilizing a controlled sampling system that simulated the most common vaping conditions. E-cigarette vapor was produced from each device by a four-second, 40-ml controlled puff, with 30-second resting periods between puffs. The e-cigarette devices were manually operated to replicate real-life conditions and all samples were collected in triplicate to verify and confirm results. Specific care was taken to avoid “dry puff” conditions.

e-cigarettes provide further proof that the flavoring compounds, not the carrier e-liquid solvents (most commonly propylene glycol and/or vegetable glycerin) dominated production of aldehydes during vaping, the authors performed a series of experiments in which a test flavored e-liquid was diluted with different amounts of the unflavored e-liquid. Liquids with higher flavor content produced larger amounts of aldehydes due to pyrolysis of the flavoring compounds.

In all experiments, the amount of aldehydes produced by the flavored e-cigarette liquids exceeded the American Conference of Governmental Industrial Hygienists Threshold Limit Values (TLVs) for hazardous chemical exposure.

“One puff of any of the flavored e-liquids that we tested exposes the smoker to unacceptably dangerous levels of these aldehydes, most of which originates from thermal decomposition of the flavoring compounds,” said Khlystov. “These results demonstrate the need for further, thorough investigations of the effects of flavoring additives on the formation of aldehydes and other toxic compounds in e-cigarette vapors.”

This research was independantly funded by the Desert Research Institute and conducted in DRI’s Organic Analytical Laboratory located in Reno, Nevada.

“Flavoring Compounds Dominate Toxic Aldehyde Production During E-cigarette Vaping”

DOI # – 10.1021/acs.est.6b05145 – http://pubs.acs.org/doi/abs/10.1021/acs.est.6b05145

 

DRI scientists used a controlled sampling system to simulate the most common vaping conditions. E-cigarette vapor was produced from each device by a four-second, 40-ml controlled puff, with 30-second resting periods between puffs. Credit DRI.

DRI scientists measured concentrations of 12 aldehydes in aerosols produced by three common e-cigarette devices shown here. Credit DRI

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