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Allergic contact dermatitis following exposure to essential oils

  • University of Auckland Medical School, Waikato Clinical Campus, Hamilton, New Zealand

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Allergic contact dermatitis from the topical use of essential oils is not widely recognized as an occupational hazard. Four cases of allergic contact dermatitis to essential oils occurring in three aromatherapists and one chemist with a particular interest in aromatherapy are described. All presented with predominantly hand dermatitis and demonstrated sensitization to multiple essential oils. One patient developed a recurrence of cutaneous symptoms following ingestion of lemongrass tea. Workers within this industry should be aware of the sensitization potential of these products and the risk of limiting their ability to continue employment.
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The exposure to essential, or volatile, oils in an occupational
setting is increasing with the burgeoning popularity of
natural therapies in Anglo-Saxon cultures. Aromatherapy is
the use of essential oils topically or by inhalation to promote
physical and psychological well-being.1Essential oils are
aromatic substances that are extracted from many different
plants and a small number of animals, or that can be synthe-
sized from coal and petrolatum.2The oil can be extracted from
plants and flowers by several methods including distillation,
extraction, enfleurage, maceration and expression.2The
composition of essential oils is highly variable. Each oil may
have over 100 constituents; the same botanical species may
produce oils containing differing components and concen-
trations.1The principal constituents of essential oils are
monoterpene and sesquiterpene hydrocarbons, monoterpene
and sesquiterpene alcohols, esters, ethers, aldehydes, ketones
and oxides.1Typically, each oil has several compounds from
each major chemical group.1The spectrum of reported skin
reactions to essential oils includes allergic contact dermatitis,
irritant contact dermatitis, phototoxic reactions and contact
urticaria.3–5 We present four cases of hand dermatitis as a
result of allergic contact dermatitis following exposure to
essential oils.
Case 1
A 52-year-old female masseur and aromatherapist presented
with a 12-month history of hand and later forearm dermatitis.
The rash improved substantially when she was absent from
work and recurred upon her returning. Standard patch testing
was performed using aluminium Finn chambers with read-
ings at 48 and 96 hours, to an extended standard series, a
cosmetic series, a fragrance series and her own massage
oils. The positive reactions are presented in Table 1. The
aromatherapist subsequently developed a small area of
dermatitis on her forearm following ingestion of lemongrass
tea and Thai food.
Case 2
A 46-year-old female masseur and aromatherapist presented
with a 3-year history of hand and forearm dermatitis. The rash
improved upon cessation of her employment. She had a past
history of hayfever and a family history of atopy. Standard
patch testing was performed using aluminium Finn chambers
with readings at 48 and 96 hours to an extended standard
series, a cosmetic series, a fragrance series, a limited plant
series and her own massage oils. The positive reactions are
presented in Table 1. In addition, the patient demonstrated a
positive patch-test reaction to her own massage oil, which
contained a mix of almond, ylang ylang, neroli, sandalwood
and frankincense oils.
Case 3
A 45-year-old natural therapist presented with a 3-year history
of hand dermatitis, which extended to involve her face and
neck 2 weeks prior to presentation. The eruption resolved
completely while on a 2-week holiday. Patch testing to the
Australasian Journal of Dermatology (2002) 43, 211–213
Allergic contact dermatitis following exposure
to essential oils
Narelle Bleasel,1Bruce Tate1and Marius Rademaker2
1Skin and Cancer Foundation, Carlton, Victoria, Australia, and
2Health Waikato, Hamilton, New Zealand
Allergic contact dermatitis from the topical use of
essential oils is not widely recognized as an occupa-
tional hazard. Four cases of allergic contact dermatitis
to essential oils occurring in three aromatherapists and
one chemist with a particular interest in aromatherapy
are described. All presented with predominantly hand
dermatitis and demonstrated sensitization to multiple
essential oils. One patient developed a recurrence of
cutaneous symptoms following ingestion of lemongrass
tea. Workers within this industry should be aware of
the sensitization potential of these products and the risk
of limiting their ability to continue employment.
Key words: Bulgarian rose oil, hand dermatitis,
lavender oil, natural therapist, occupational skin
disease, ylang ylang oil.
Correspondence: Dr B Tate, Skin and Cancer Foundation,
95 Rathdowne St, Carlton, Vic. 3053, Australia.
Narelle Bleasel, MB BS. Bruce Tate, FACD. Marius Rademaker,
Submitted 22 October 2001; accepted 15 January 2002.
European standard series (Chemotechnique, Malmo, Sweden),
antimicrobials, an extended fragrance series and
her own massage oils was performed using IQ chambers
(Chemotechnique), with readings at 48 and 96 hours. The
positive reactions are presented in Table 1.
Case 4
A 29-year-old analytical chemist, with a part-time occupa-
tional interest in aromatherapy and massage, presented with
a 1-month history of hand dermatitis. The rash became more
widespread to involve her face and neck prior to presentation.
Relevant past history included hayfever and scabies. Patch
testing to the European standard series (Chemotechnique),
a cosmetic series, a fragrance series, and the patient’s own
massage oils was performed using IQ chambers (Chemo-
technique) with readings at 48 and 96 hours. The positive
reactions are presented in Table 1.
Reactions were graded according to the International
Contact Dermatitis Research Group grading system.
The frequency of allergic contact dermatitis associated with
essential oil usage is unknown and at present there have been
only limited reports of this association in the natural therapy
industry.6–9 This may represent low incidence of sensitization
to these compounds, or a failure to recognize allergic contact
dermatitis within this occupation and subsequent under-
reporting. Allergic contact dermatitis related to essential
oils has been reported in several other occupational groups,
including bar workers,10 citrus fruit pickers,11 a hairdresser,12
a physiotherapist,13 a beautician14 and manufacturers of
Determining the sensitizing agent responsible for skin
reactions associated with an essential oil is difficult, because
of the many components and their variable concentrations
within an oil.1In addition, the components of an essential oil
often undergo complex interactions that result in reducing
the sensitization potential of an individual compound
when combined in an oil mixture.1,5 This is known as the
quelching effect.1,5 Indeed, a degradation product may be
the sensitizing agent.1,3
The four cases presented developed a delayed type allergy
to essential oils following exposure in an occupational setting.
In all cases, multiple sensitizations were demonstrated.
Case 1 displayed positive patch-test reactions to several
essential oils that she had not previously been exposed to,
including palmarosa, frankincense, rose, neroli and myrrh.
Linalool was a common constituent amongst this group of
sensitizing oils, with the exception of myrrh, implicating
cross-reactivity.17,18 Of note, this patient had a positive patch-
test reaction to lemongrass and described a recurrence of
dermatitis following ingestion of lemongrass-containing foods.
The phenomenon of systemic contact dermatitis has pre-
viously been described in relation to Matricaria chamomilla
Case 2 exhibited sensitivity to geraniol, a component of
lavender, rose, geranium, ylang ylang, lemongrass, cananga,
sandalwood and neroli.17,18 This may account for her sensi-
tivity to these products. In addition this patient displayed
sensitivity towards peppermint, laurel and yarrow, products
which do not contain geraniol.17,18 Limonene is a common
component in this second group of oils; however, sensitivity
to this compound was not tested.17,18
Geraniol is a common constituent of the oils case 3 devel-
oped sensitization reactions to;17,18 however, the patient did not
exhibit sensitivity to geraniol. Similarly, the positive reactions
seen in case 4 could be accounted for by sensitivity to geraniol;
however, no primary reaction to geraniol was present.
Of note, three of the four cases presented had positive
patch-test reactions to fragrance mix. The constituents of
fragrance mix are cinnamic alcohol, cinnamic aldehyde,
-amyl cinnamic aldehyde, eugenol, isoeugenol, geraniol,
hydroxycitronella and oak moss.20 Six of these eight fragrance
ingredients are also components of essential oils (including
cinnamic alcohol, cinnamic aldehyde, eugenol, isoeugenol,
geraniol).4Fragrance mix is a common allergen, with approxi-
mately 1% of the unselected population demonstrating sensi-
tivity.21 Patients with positive patch-test reactions to fragrance
mix often react to essential oils. One study demonstrated that
57% of patients with positive reactions to fragrance mix also
reacted to one or more essential oils.22 However, testing solely
with fragrance mix or its constituents will not reliably detect
all patients allergic to essential oils. Patients can be tested to
the commercially available allergens in the Chemotechnique
fragrance series.
The use of essential oil-based products in people’s homes
is also now popular and leading to reports of allergic contact
dermatitis.23–25 Many cosmetics and perfumes contain essen-
tial oils and are likely to be important allergens.5,20,22,26 In
Japan, an increase in the frequency of positive patch tests to
lavender oil was reported between 1990 and 1998.25 A tele-
phone survey of these patients suggested the main source of
exposure to the lavender allergens was products containing
dried lavender flowers.
These cases highlight the importance of allergic contact
dermatitis associated with essential oil exposure in an
occupational setting. It appears that multiple sensitizations
are a common occurrence. Therefore, avoidance of a single
212 N Bleasel et al.
Table 1 Results of patch tests
Test substance Case 1 Case 2 Case 3 Case 4
Fragrance mix + + +
Cananga oil 2.0% –+–+
Geraniol 2.0% +
Geranium oil Bourbon 2.0% + + +
Frankincense 5.0% + NT NT NT
Lavender absolute 2.0% ++++
Lavender oil 2.0% + NT NT NT
Laurel oil 2.0% + NT NT
Lemongrass oil 2.0% + + NT NT
Myrrh 5.0% + NT NT NT
Neroli oil 2.0% + NT NT
Palmarosa 5.0% + NT NT
Peppermint oil 2.0% + NT NT
Rose oil, Bulgarian 2.0% ++++
Sandalwood oil 2.0% + + +
Yarrow + NT NT
Ylang ylang oil 2.0% + + +
+, positive reaction; –, negative reaction; NT, not tested.
oil is unlikely to prevent further episodes of allergic contact
dermatitis. In addition, the concurrent reaction to fragrance
mix may pose further limitations on product selection.
Employees within the aromatherapy and masseur industry
should be aware of the sensitization potential of the oils that
they use in their workplace. Sensitization to essential oils may
have serious ramifications, as the employees may be unable
to continue in their chosen field of work. It is also necessary
to consider allergy to essential oils in clients of aromathera-
pists and people using them at home.
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Contact dermatitis to essential oils 213
214 N Bleasel et al.
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... No specific data were provided by the applicant regarding the safety of the additive for users. However, published reports (Bleasel et al., 2002;de Groot and Schmidt, 2016) have identified ylang ylang oil as a potential contributor for skin allergy and dermatitis and on this basis, it should be considered a dermal sensitiser. This is reinforced by the classification assigned on the safety data sheets. ...
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Hair is biologically diverse with a range of textures and thicknesses. Hair also serves as expression of oneself; leading to hair care practices and styling that are influenced by culture, perception of beauty, and environment. The use of hair oils, styling and hair restructuring processes are utilized to help manage and style hair, along with offering options for self-expression. These hair care practices can lead to a range of complications, including contact dermatitis, seborrheic dermatitis, and scarring alopecias.
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The purpose of this study was to determine the frequency of responses to selected fragrance materials in patients who were fragrance sensitive. 178 patients were evaluated in 8 centers worldwide with a fragrance mix (FM) and 20 other fragrance materials. Reaction to the fragrance mixture (FM) occurred in 78.7% of the subjects. Substances reacting at a rate of 2% or higher included jasmine absolute, geranium oil bourbon, l-citronellol, spearmint oil, 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-gamma-2-benzopyran, omega-6-hexadecenlactone, dimethyltetrahydrobenzaldehyde (isomer mixture), and alpha-amylcinnamaldehyde. These chemicals should be furthur evaluated to corroborate their allergenicity. We are constantly looking for new fragrance allergens to extend the diagnostic capability of the fragrance mix (FM)
Aromatherapy is a form of alternative medicine (complementary therapy, holistic practice) using essential oils systemically or topically. Aromatic substances extracted from flowers have been used for medical purposes from ancient times. The term ‘aromatherapy’ was introduced in 1936 by René-Maurice Gattefossé, a French chemist, after he had used lavender oil to heal his burned hand (Weiss and James 1997). According to the International Federation of Aromatherapists, aromatherapy enhances well-being, relieves stress, and helps in the rejuvenation and regeneration of the human body’. Aromatherapists also claim that it can help in stress-related conditions, premenstrual syndrome, moderate anxiety or depression, sleeping problems, minor aches and pains, migraine, digestive disorders, skin problems such as eczema and acne, and minor infections such as thrush and cystitis (Trevelyan 1993). Aromatherapy has become increasingly popular in recent years together with other so-called alternative treatments.
The second edition of this book is virtually a new book. It is the only comprehensive text on the safety of essential oils, the first review of essential oil/drug interactions, and it provides detailed essential oil constituent data not found in any other text. Much of the existing text has been re-written, and 80% of the text is completely new. There are 400 comprehensive essential oil profiles and almost 4000 references. There are new chapters on the respiratory system, the cardiovascular system, the urinary system, the digestive system and the nervous system. For each essential oil there is a full breakdown of constituents, and a clear categorization of hazards and risks, with recommended maximum doses and concentrations. There are also 206 Constituent Profiles. There is considerable discussion of carcinogens, the human relevance of some of the animal data, the validity of treating an essential oil as if it was a single chemical, and the arbitrary nature of uncertainty factors. There is a critique of current regulations.
We report the annual results of patch testing with lavender oil for a 9-year period from 1990 to 1998 in Japan. Using Finn Chambers and Scanpor tape, we performed 2-day closed patch testing with lavender oil 20% pet. on the upper back of each patient suspected of having cosmetic contact dermatitis. We compared the frequency of positive patch tests to lavender oil each year with those to other fragrances. We diagnosed contact allergy when patch test reactions were + or <+ at 1 day after removal. The positivity rate of lavender oil was 3.7% (0–13.9%) during the 9-year period from 1990 to 1998. The positivity rate of lavender oil increased suddenly in 1997. Recently, in Japan, there has been a trend for aromatherapy using lavender oil. With this trend, placing dried lavender flowers in pillows, drawers, cabinets, or rooms has become a new fashion. We asked patients who showed a positive reaction to lavender oil about their use of dried lavender flowers. We confirmed the use of dried lavender flowers in 5 cases out of 11 positive cases in 1997 and 8 out of 15 positive cases in 1998. We concluded that the increase in patch test positivity rates to lavender oil in 1997 and 1998 was due to the above fashion, rather than due to fragrances in cosmetic products.