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Volatile chemical emissions from essential oils with therapeutic claims

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Abstract

Essential oils emit many volatile organic compounds (VOCs), with some considered potentially hazardous. However, little is known about specific emissions from essential oils that make therapeutic claims for health and well-being. This study investigated VOCs emitted from 14 commercially available essential oils with therapeutic claims, such as beneficial for coughs, colds, flus, relaxation, sleep, tension, headaches, stress, or skin irritation. The essential oils were selected from different brands and types, such as tea tree oil, lavender oil, eucalyptus oil, geranium oil, peppermint oil, bergamot oil, orange oil, and oil blends. Analyses were performed using headspace gas chromatography/mass spectrometry (GC/MS). The analyses found 1034 VOCs emitted from the 14 essential oils, representing 378 VOC identities. The most prevalent VOCs (in more than 90% of the oils) were acetaldehyde, alpha-phellandrene, alpha-pinene, camphene, limonene, methanol, terpinolene, 3-carene, acetone, beta-phellandrene, ethanol, and gamma-terpinene. Among the 1034 VOCs emitted, 251 VOCs, representing 60 VOC identities, are classified as potentially hazardous. The most prevalent potentially hazardous VOCs were acetaldehyde, limonene, methanol, acetone, ethanol, and 3-carene. Toluene was found in more than 70% of the essential oils. Each of the essential oils emitted 9 or more potentially hazardous VOCs. Fewer than 1% of all VOCs identified and fewer than 1% of all potentially hazardous VOCs were listed on any essential oil label, safety data sheet, or website. Results from this study provide new findings on VOC emissions from essential oils with therapeutic claims, which can help to improve public awareness about potential exposures and risks.
Volatile chemical emissions from essential oils
with therapeutic claims
Neda Nematollahi
1
&Justine Lew Weinberg
2
&Jennifer Flattery
3
&Nigel Goodman
4
&Spas D. Kolev
5
&
Anne Steinemann
1,6
Received: 20 August 2020 / Accepted: 3 September 2020
#Springer Nature B.V. 2020
Abstract
Essential oils emit many volatile organic compounds (VOCs), with some considered potentially hazardous. However, little is
known about specific emissions from essential oils that make therapeutic claims for health and well-being. This study investigated
VOCs emitted from 14 commercially available essential oils with therapeutic claims, such as beneficial for coughs, colds, flus,
relaxation, sleep, tension, headaches, stress, or skin irritation. The essential oils were selected from different brands and types, such
as tea tree oil, lavender oil, eucalyptus oil, geranium oil, peppermint oil, bergamot oil, orange oil, and oil blends. Analyses were
performed using headspace gas chromatography/mass spectrometry (GC/MS). The analyses found 1034 VOCs emitted from the 14
essential oils, representing 378 VOC identities. The most prevalent VOCs (in more than 90% of the oils) were acetaldehyde, alpha-
phellandrene, alpha-pinene, camphene, limonene, methanol, terpinolene, 3-carene, acetone, beta-phellandrene, ethanol, and gam-
ma-terpinene. Among the 1034 VOCs emitted, 251 VOCs, representing 60 VOC identities, are classified as potentially hazardous.
The most prevalent potentially hazardous VOCs were acetaldehyde, limonene, methanol, acetone, ethanol, and 3-carene. Toluene
was found in more than 70% of the essential oils. Each of the essential oils emitted 9 or more potentially hazardous VOCs. Fewer
than 1% of all VOCs identified and fewer than 1% of all potentially hazardous VOCs were listed on any essential oil label, safety
data sheet, or website. Results from this study provide new findings on VOC emissions from essential oils with therapeutic claims,
which can help to improve public awareness about potential exposures and risks.
Keywords Essential oils .Therapeutic .Emissions .Volatile organic compounds .Hazardous compounds .Fragrance .
Ingredients
Introduction
Essential oils with therapeutic claims are widely used in many
public and private places for different purposes, such as aro-
matherapy, antibacterial effects, and alleviation of cold and flu
symptoms. Essential oils, such as tea tree oil, lavender oil,
eucalyptus oil, peppermint oil, and orange oil, are complex
mixtures of many different compounds (e.g., Milhem et al.
2020; Nematollahi et al. 2018a; Huang et al. 2012).
Numerous studies have examined potential health benefits
of essential oils. For example, Shaaban et al. (2012)reviewed
bioactivities associated with essential oils, including antibac-
terial, antiviral, anti-inflammatory, and additional properties.
More specifically, Cavanagh and Wilkinson (2002)reviewed
the physiological and psychological effects associated with
lavender oil.
However, relatively few studies have examined potential
hazards of essential oils. Exposure to essential oils has been
associated with adverse health effects such as skin irritation
Electronic supplementary material The online version of this article
(https://doi.org/10.1007/s11869-020-00941-4) contains supplementary
material, which is available to authorized users.
*Neda Nematollahi
neda.nematollahi@unimelb.edu.au
1
Department of Infrastructure Engineering, Melbourne School of
Engineering, The University of Melbourne, Parkville, VIC 3010,
Australia
2
Public Health Institute, Contractor to Occupational Health Branch,
California Department of Public Health, Richmond, CA 94804, USA
3
Occupational Health Branch, California Department of Public
Health, Richmond, CA 94804, USA
4
School of Property Construction and Project Management, RMIT
University, Melbourne, VIC 3000, Australia
5
School of Chemistry, The University of Melbourne,
Parkville, VIC 3010, Australia
6
College of Science and Engineering, James Cook University,
Townsville, QLD 4814, Australia
https://doi.org/10.1007/s11869-020-00941-4
/ Published online: 18 September 2020
Air Quality, Atmosphere & Health (2021) 14:365–369
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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