Aerosol Composition Testing of Concerning Compounds

Reduced Risk Nicotine
Written By Samantha Wright

Authors:
Matthew Culpepper, Director of Analytical Chemistry and Formulation Development, Pneuma Respiratory; Guangxi Li, MD, Professor of Medicine, Director of Pulmonary and Critical Care Medicine, Guang’anmen Hospital, China Academy of Chinese Medical Science; Mingwan Su, PhD, China Academy of Chinese Medical Science

Study Objective: This study was performed to compare the amounts of concerning compounds in the emissions of several inhaled nicotine products. The compounds of interest included heavy metals (chromium, iron, nickel, copper, zinc, arsenic, cadmium, tin, silver, lead, beryllium, cobalt, selenium, and vanadium) and organic compounds (acetaldehyde, acrolein, butyraldehyde, crotonaldehyde, diacetyl, formaldehyde, furfural, pentanedione, acrylonitrile, and benzene).

Study Design: The study was performed by a third-party laboratory, McKinney Specialty Labs. McKinney is a laboratory with extensive experience in analyzing nicotine-containing products.

The products chosen for this testing are as follows:

  • Pneuma’s device (1.8% nicotine solution)

  • Vape device (1.8% nicotine solution)

  • Heat-not-burn device (tobacco sticks)

The devices were ejected into filter pads to collect the samples. Once the samples were collected, tests were run using gas chromatography with flame ionization detection and thermal conductivity detection to determine the amounts of organic compounds present. The amounts of heavy metals were determined using inductively coupled plasma mass spectrometry. The heat-not-burn device heats the tobacco product directly, whereas the vape device heats a liquid containing nicotine to create vapor.

Key Findings:

  • Pneuma’s device did not show any quantifiable levels of the heavy metals or organic compounds that were tested.

  • The vape device had quantifiable levels of copper, nickel, and zinc. Additionally, the organic compound testing showed quantifiable levels of acetaldehyde, acrolein, diacetyl, and formaldehyde from the vape device.

  • The heat-not-burn device showed no quantifiable levels of heavy metals but had quantifiable levels of all 10 of the organic compound tested.

Conclusions & What the Results Mean:

  • The results of the study showed no quantifiable levels of the included heavy metals or organic compounds from Pneuma’s device. The vape device produced quantifiable levels of certain metals and organic compounds, while the heat-not-burn device produced quantifiable levels of all of the tested organic compounds.

  • The vape and heat-not-burn devices both use high levels of heat to produce vapor from a liquid containing nicotine and a stick containing tobacco, respectively. Pneuma’s device, on the other hand, does not use heat to produce aerosol, in addition to using a water-based solution.

  • The results of the study support the conclusion that a device that delivers nicotine without the use of heat does not produce quantifiable levels of chemical byproducts commonly found in vape and heat-not-burn devices.

Detailed Results:
The following tables show the detailed results of the study, as well as the potential harmful health effects of each measured chemical.

  • Copper fumes cause upper respiratory tract irritation, metallic taste, nausea, and metal fume fever.

  • Nickel issues depend on the dose and length of exposure, as an immunotoxin and carcinogen agent. Nickel can cause a variety of health effects, such as contact dermatitis, cardiovascular disease, asthma, lung fibrosis, and respiratory tract cancer. Inhalation exposure in occupational contexts is a main route for nickel-induced toxicity in the respiratory tract, lungs, and immune system.

  • Zinc can produce irritation and corrosion of the gut, acute renal tubular necrosis and interstitial nephritis. Inhalation would presumably contribute partially to pathological effects on the kidneys.

  • Acetaldehyde exposure by inhalation caused tumors in two rodent species. Inhalation of acetaldehyde also promoted the induction of respiratory-tract tumors by intratracheal instillation of the known carcinogen benzo[a]pyrene in hamsters of both sexes. Acetaldehyde was listed in the Sixth Annual Report on Carcinogens.

  • Acrolein is irritating to the eyes, nose, and throat and causes a decrease in respiratory rate. At higher concentrations, coughing, pulmonary edema, bronchitis, or tracheobronchitis may occur.

  • Butyraldehyde, when inhaled, can irritate the lungs causing coughing and/or shortness of breath. Higher exposures can cause a build-up of fluid in the lungs (pulmonary edema), with severe shortness of breath.

  • Crotonaldehyde causes eye, skin, and respiratory irritation. The International Agency for Research on Cancer does not classify crotonaldehyde, as there is currently no human data to prove its carcinogenicity, but the U.S. Environmental Protection Agency has classified this chemical as a possible human carcinogen due to evidence shown in animal studies.

  • There is limited evidence available pertaining to the inhalation of diacetyl through smoking and e-cigarette use, but studies on occupational exposure conclude that inhalation of diacetyl causes bronchiolitis obliterans, also known as popcorn lung.

  • Formaldehyde is classified as a known human carcinogen (group 1) by the International Agency for Research on Cancer. Its carcinogenicity is attributed to genotoxicity and cytotoxicity.

  • Furfural causes respiratory irritation in humans.

  • Pentanedione is an analog of diacetyl and has the same effects as diacetyl.

  • Acrylonitrile causes respiratory irritation and neurological symptoms such as convulsions and is presumed to cause gastrointestinal irritation. The International Agency for Research on cancer has classified acrylonitrile as a possible human carcinogen.

  • Exposure to benzene has been linked with a higher risk of cancer such as leukemia, particularly acute myeloid leukemia. Benzene has been shown to cause chromosome changes in bone marrow cells in the lab. Benzene can result in anemia, low white blood cell count, and low blood platelet count.

Author Backgrounds:

  • Matthew Culpepper, Director of Analytical Chemistry and Formulation Development, Pneuma Respiratory

    • Research scientist at Argonne National Laboratories

    • Researcher and professor at University of Chicago and Northwestern University

    • R&D department at Therapeutic Proteins, Inc. Responsible for upstream and downstream analysis of biosimilar drugs

  • Guangxi Li, MD, Professor of Medicine, Director of Pulmonary and Critical Care Medicine, Guang’anmen Hospital, China Academy of Chinese Medical Science

    • Assistant Professor of Medicine, Pulmonary and Critical Care Medicine, Mayo Clinic, Mayo Epidemiology and Translational Research in Intensive Care (METRIC)

    • Visiting Scientist at Pulmonary and Critical Care Division, Mayo Clinic

  • Mingwan Su, PhD, China Academy of Chinese Medical Science

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Samantha Wright
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