オール・アバウト・レモンマートル

レモンマートルとは？
オーストラリアクイーンズランド州の多雨林を原産とする植物の名称です。

■レモンマートル
■レモンマートルの学名
■レモンマートルの葉
■Pengelly Report
■「レモンよりレモン」の言いだしっぺ

レモンとマートルのブレンドではありません。
イギリスの植生学者バックハウス卿（James Backhouse）がオーストラリア原住民アボリジニの生活から発見しました。
レモンマートルはアボリジニが古来から薬草として活用していました。
バックハウス卿にちなみ、学術名を「バックハウジア・シトリオドーラ」と呼ばれるようになりました。

■海外文献より
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The botanical name of lemon myrtle, Backhousia citriodora, was a tribute to James Backhouse, an English botanist. The name was given by Baron Ferdinand von Mueller, a German botanist who was curator of the Melbourne Botanical Gardens in 1853; the species name includes reference to the citrus taste of the leaves.
↑
レモンマートルの植物学名バクホウシア・シトリオドラは、イギリス人植生学者ジェームズ･バックハウス卿にちなんだものです。学名自体は、ドイツ人植生学者であり１８５３年当時のメルボルン植物園の園長であったバロン・フェルディナンド・フォン・ミュラーにより、レモンマートル葉の柑橘（シトラール、シトラルなど）テイストも加味した上で名づけられました。
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レモンマートルは、湿潤の多雨林地帯でしかうまく育たないため、栽培が難しい植物です。
日本でごく少々、米国カリフォルニア州でも少し栽培されていますが、風味などは別物です。
その葉に含むエッセンシャルオイルは、９８％がシトラールで２％がシトロネラールという成分です。
シトラールこそが、レモンで広く知られる柑橘の芳香を出しています。
一時、リモネン成分がその芳香のもととされていましたが、間違いです。
シトラールは、世界中で研究されています。
各エッセンシャルオイル中、
レモンマートル＝約９８％
ティトリー＝約８５％
レモングラス＝約８０％
レモンバーム＝約６０％
そしてレモン＝約６％
の割合のシトラールが含まれています。

■レモンマートルのエッセンシャルオイル
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This popular oil has a vibrant aroma of lemon with a menthol back note. It is native to rainforest on the south Qld coast.

Suggested uses: Common cold, influenza, bronchitis, indigestion and herpes simplex (topical). It has been found to be effective as relieving chest congestion. It also seems useful for improving concentration as well as being relaxing, uplifting emotionally and producing soothing sleep. Superb as an air purifier. Can be applied directly onto warts, otherwise always dilute before use as it may irritate.

↓

一般的な風邪、インフルエンザ、気管支炎、消化不良、単純ヘルペスに。
胸部うっ血を和らげる効果もある。
また、集中力を向上させつつリラックス効果・精神的高揚効果・快適な睡眠のためによい。
空気清浄面では大変素晴らしい逸品である。
イボなどに直接塗布するのもいいだろうし、気になる場合は使用する前に希釈してもいいだろう。
…とのこと。
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■海外のレモンマートル文献のまとめ（逐次、和訳を掲載してゆきます）
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Backhousia Citriodora in WIKIPEDIA

Technical Information about Lemon Myrtle Oil

[Latin Name]
Backhousia Citriodora

[Family]
Myrtaceae

[Common Names]
Lemon-scented myrtle, Sweet verbena tree; Lemon ironwood. Origin: Rainforests of south east Queensland.

[Description]
A pale yellow or yellow mobile liquid of intensely fresh lemon-like odor with a pleasant sweet-green undertone. Its odour is much cleaner and fresher than Lemongrass oil and there are no grassy-fatty notes. Even the amylacetate-like fruitiness of Lemongrass oil is absent in B. citriodora.

Backhousia is a rare genus of 8 species of trees, characterised by opposite, shiny and strongly aromatic leaves. In rainforests, B. citriodora grows wild up to 30m high with lanceolate, strongly lemon-scented leaves. In early summer the tree is covered by clusters of tiny white four-petalled flowers. The tree prefers a moist climate and is frost sensitive. Propogation is by cuttings taken in spring.

[Constituents]
Leaves contain 1.5 - 2.0% essential oil consisting almost entirely of citral (85-97%).

[Properties of essential oil]
Citral is an aliphatic aldehyde in the monoterpenoid class. In plants such as lemongrass (Cymbopogon) and lemon balm (Melissa officinalis), citral occurs as two isomeric aldehydes, neral and geranial. Relative density: 0.89, refractive index 1.4928, optical rotation 1.0, solubility in 70% v/v ethanol 20 degrees C: 1.5ml.

[Actions]
Besides being antiviral, antibacterial, and germicidal as shown previously, it is also sedative (4), antifungal (5), antiseptic, carminative and corrective.

[Indications]
Common cold, influenza, bronchitis, indigestion and other irritable gastrointestinal disorders, herpes simplex - apply topically over area or on reflex points of feet. If caustic to sensitive skin, dilute with carrier oil. For sensitive skin, dilute 2 drops in one ounce of carrier oil. Do not use the oil directly on skin. Always dilute.

[Applications]
As an acne cream it would be vastly more effective than other products on the market. As B. citriodora has 25% more activity against a range of microorganisms than melaleuca (phenol coefficient of 16 versus 12) it would do well in preparations such as shampoos, toothpaste, hand soaps, antiseptic lozenges, deodorizers, dental applications, throat gargles, mosquito/insect repellants, cleaning formulations, veterinary products (flea repellant) and perfumes. One or more drops of citriodora makes an excellent tea and gargle. Even rock stars gargle herbal tea with B. citriodora added to an a herbal infusion to help with raw throats. Many people are reporting improvements using B. citriodora diluted in carrier oil topically on psoriasis, rashes, folliculitis, neuro-dermatitis, itching, tinea, candidiasis and headaches. It can effectively deter the most persistent case of ant colonies roaming a house with just a few countertop applications.

The main constitutent of lemon myrtle oil, citral, in tests against fungus, proved very active, more so than camphor. Essential oils, direct their action to the microorganisms’ cell membrane. Their activity is broad spectrum thus reducing the possibility of microorganisms developing a resistance.

In fact, whatever conditions are helped by Lemongrass or Melissa oils (e.g. depression) will receive even more benefit from lemon myrtle oil simply by virtue of the fact that it contains more citral.

Some people have reported mind-altering states as a result of sitting quietly and one­pointedly inhaling the vapors from a bottle.

[Modes of Application]
Use topically (always dilute with carrier oil to avoid irritating the skin), add small amounts (1 or 2 drops) to beverages and drinks as flavoring, wipe on counters, add to cleaning agents, shampoos, liquid soaps. Avoid prolonged inhalation via diffusion. Do not add to douches or enemas!

[A Rare Oil]
Main B. citriodora forests near Gympie, Queensland were destroyed during World War II when a famous soft drink company in Australia could no longer obtain Lemongrass oil from India to flavor their drinks. They found the citral content in B. citriodora met their requirements so eventually the forests were severely depleted. A few companies now plantation-grow this unique resource so that endemic strands are no longer under threat of extinction.

[The Source]
Our supplier is committed to producing a superior quality organic product. The trees are grown approximately 2-3 metres high and are irrigated with mineral water. Organic farming principles are followed (no organochlorines or organosulphides) using natural fertilizers, mulch, microbes, rock dust and natural pest control. No synthetic insecticides are employed (the high citral content of B. citriodora repels most insects).The biomass is steam distilled then the oil is double filtered. No chemicals or solvents are used in the process.

As all new plants of a selected cultivar must be propagated asexually (cuttings), are difficult and slow to strike, require good soils to prosper, be on elevated land not subject to frost and given that it is a rare oil, the cost is expensive relative to other citral oils. However, the potency of B. citriodora means extensive dilution is possible, thereby reducing its actual cost.

[Other Species]
There are eight species of Backhousia all having aromatic foliage (viz. B. anisata, B. angustifolia, B. bancroftii, B. citriodora, B. hughesii, B. myrtifolia, B. sciadophora, B. kingii). B. citriodora. appears to have the highest level of citral of any plant in the world, ranging from 85-97% (Lemongrass oil is 75-85%).

[History]
Though an attempt to link all the known Backhousia oils together has been made, it is easier to describe work previously done on individual species. Schimmel & Co. was the first to investigate B. citriodora over 100 years ago and found it to’contain 95% citral. In 1920 John Blogg noted its citral content could be used to produce ionone (the highly aromatic component found in violets which is extremely hard to produce synthetically) (7). A few years later Penfold et al. reported the existence of a chemical variety of B. citriodora which contained 1-citronellal and d-isopulegol. Attempts to relocate this species were unsuccessful and the species remained hidden for nearly fifty years until recently rediscovered.

[Toxicity]
None reported. Citral is found in fresh fruits and has a long history of acceptance by U.S. and European regulatory bodies and has been accorded GRAS (generally recognized as safe) status. Some studies performed on rats using .3glk essential oil of B. citriodora led to impaired reproductive function and prostatic enlargement in some animals, but not in others. Citral is reported to promote increased intraocular pressure in test animals, but a subsequent study failed to support this. Bear in mind, also that for therapeutic use, humans are only likely to be using a few drops of this oil at a time. Not only that, the results of animal research can never be accurately extrapolated to humans. If citral was dangerous for human health, it would not be possible to sell hundreds of thousands of tonnes of Lemon oil (which also contains citral), annually around the world!

Metabolic studies show that when minute quantities of citral are used as food flavoring, it is rapidly extracted from the food, altered into a more water-soluble form using specialized enzymes in the liver, sent to the kidneys and excreted in the urine so there is no accumulation of this chemical component in body lipids.

Because it has the world’s highest concentration of citral, without question, this is a very important oil for the aromatherapy and herbal industries along with personal hygiene products, food and beverages (both hard and soft). Already, the Japanese are very interested in adding B. citriodora to their tea for flavor enhancement. Its taste is very smooth, clean, lemon-like and pleasant. Some herbal practitioners like to add B. citriodora to teas and extract/tincture compounds to vastly improve the flavor and also to provide anti-microbial and possible immunostimulating benefits, so helpful during winter months.

As our world becomes more and more toxic with its corresponding negative effect on our first line of defense: the immune system, this potently anti-microbial essential oil deserves a place among some of the most therapeutic oils the world has to offer.

■[References]
Schnaubelt K., Potential Application of Essential Oil in Viral Disease, Int. J. Aromatherapy, 1988/89, 1/2:33
　⇒海外サイト本文
　⇒当サイト内和訳ページ

Atkinson W. & Brice H., Anti-Bacterial Action of Essential Oil from Some Australian Plants, Aust. J. Exp. Biology 1955, 33:547
　⇒（現在、未発見、無いかもしれません、古すぎます）

Pengelly A., Australian Medicinal Plant, Aust. J. Med.
　⇒海外サイト本文
　⇒当サイト内和訳ページ
　⇒Mr. Andrew Pengelly

Herbalism, Vol 3 (3) 1991 Schnaubelt K.
　⇒海外サイト本文（現在未発見）
　⇒当サイト内和訳ページ
　⇒Schnaubelt著　１・２

Friendly Molecules, Int. J. Aromatherapy 1989, 2:20
　⇒海外サイト本文（現在未発見）
　⇒当サイト内和訳ページ

Moleyar V. & Narasimbam P., Mode of Anti-Fungal Action of Essential Oil Components: Citral and Camphor, Indian J. Exp. Biology 1987:25:781
　⇒海外サイト本文
　⇒当サイト内和訳ページ

Tisserand R., The Essential Oil Safety Data Manual, Sussex - Tisserand Aromatherapy Institute, 1988
　⇒海外サイト本文
　⇒当サイト内和訳ページ

Blogg J., Some Australian Essential Oils, Science & Industry 1920 Vol 2: 242
　⇒海外サイト本文（具体的文献は現在未発見）
　⇒当サイト内和訳ページ

Australian Plant Name Index APNI
　⇒海外サイト本文
　⇒当サイト内和訳ページ
　⇒オーストラリア政府農林水産省

Hayes AJ, Markovic B. "Toxicity of Australian essential oil Backhousia citriodora (Lemon myrtle). Part 1. Antimicrobial activity and in vitro cytotoxicity." Food Chem Toxicol. 40(4):535-43 (2002).
Hayes AJ, Markovic B. "Toxicity of Australian essential oil Backhousia citriodora (lemon myrtle). Part 2. Absorption and histopathology following application to human skin." Food Chem Toxicol. 41(10):1409-16 (2003).
　⇒海外サイト本文
　⇒当サイト内和訳ページ

Burke BE, Baillie JE, Olson RD. "Essential oil of Australian lemon myrtle (Backhousia citriodora) in the treatment of molluscum contagiosum in children." Biomed Pharmacother. 58(4):245-7 (2004).
　⇒海外サイト本文
　⇒当サイト内和訳ページ

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＊上記に乗っていない情報があれば、ご提供くださいませんか？＊

オーストラリア国内においてオーガニック認定商品とは、オーストラリア政府から認可を受けている８つの認定団体のうちのいずれかにより、有機JAS認定やUSDAオーガニック認定などを正式に受けている商品をさします。

商品が、オーガニック認定を受けるためには、栽培農園や生産工場なども全てオーガニック認定を受けないといけないそうです。ACO（Australian Certified Organic）などの説明によると、
「該当農園が農薬を使用していなくても、散布農薬による土壌汚染もありえるため、認可プロセスのチェックには該当農園周辺の他農園など状況を把握したうえで該当農園の土壌チェックを行い、残留農薬がないか調べます。そこから３年間の安全を確認した後に、やっとオーガニック認定を受けることができます。」
とのこと。
詳しくは、別記事で書きますが、オーストラリアでは国をあげて「オーガニック認定（Certified Organic）」商品を守っています。

中国では、やっと「はじめて国の定めるルール」が最近（２００７年７月中旬）になってようやく考えられるようになったそうですね…

「自称オーガニック」とは、どんな商品でも謳えるキーワードで、よく市場を混乱させる言葉です。
「これはオーガニックです」と言ったとしても、USDAや有機JASやそれを認可した団体のロゴがないと、オーガニック認定ではないので要注意です。

自称オーガニックとオーガニック認定と何が違うか…
それは、残留農薬などが入っていなくて間違いなく安全だということです。
食の安全を求めるオーストラリア政府の姿勢はすばらしいと評価は絶大なんですよ。

ハーブ（一般的に薬草のこと）の葉などから、蒸気抽出されるオイルをエッセンシャルオイルと言います。

このエッセンシャルオイル中には、もちろん構成する成分があるわけです。

レモンマートルの場合、「シトラール（citral）」と呼ばれる主成分があります。
主成分ということは、エッセンシャルオイル中に多く含まれるということです。

シトラールについて、今後詳しく触れるとして、まずは主要ハーブ・植物のシトラール含有率を見てみましょう。

レモンマートル　＝　約９８％
ティトゥリー　＝　約８５％
レモングラス　＝　約８０％
レモンバーム　＝　約６０％
レモン　＝　約６％

シトラールを様々な製品に使用するために、
世界中で栽培されるレモングラスが用いられていました。

レモンマートルは、
オーストラリアのクイーンズランド州の多雨林（原生地）でしか、本来のようには育たないと言われています。クイーンズランドには、オーストラリア産のオーガニック認定レモンマートルの９０％シェアを占める農園があります。

天然のホンモノのレモンマートルでしか、本来のシトラールは採れないんですね。

２００７年７月現在、
オーストラリアには、７つのオーガニック認定団体があります。

①Australian Certified Organic (ACO)
*Organic Growers of Australia (OGA)を吸収
②National Association for Sustainable Agriculture Australia (NASAA)
③Organic Food Chain (OFC)
④Biodynamic Research Institute (BDRI)
⑤Safe Food Queensland (SFQ)
⑥Tasmanian Organic Produce (TOP)
⑦AusQual

各団体とも、厳しい認定基準を持っており、どこが悪い良いというのはないようです。
ACOが一番大きな団体であるとか、
OFCは一年毎に認定継続チェックをしているとか（２年毎のところもある）、
差異は確かにありますが、やっていることは全く同じです。

レモンマートルもそうですが、肉も穀物もなんでもオーガニック認定を受けた商品だけをオーストラリアは輸出推進していこうと動いており、今では確かオーストラリアからの輸出商品の５０％以上がオーガニック認定を受けているようです。

ただしご注意ください。
商品には、必ず認定のロゴがついています。
例）　有機JASやUSDAロゴ

この他にも、各団体のロゴやオーストラリア政府のケミカルフリーのロゴもあるんですよ。
おいおい、お話してゆきますね♪

シトラールについて（ウィキペディア参照）

このページでは、シトラールについて調べた内容を完全リストアップします。
縦に長くてすいません。

レモンマートルのシトラールという成分には、
抗バクテリア効果、抗ウイルス効果、殺菌効果、沈静作用、中和作用のちからがあります。
特に、ヘルペスウイルスを減退させる効能が大変人気です。
レモンマートルからシトラールをティなどで摂取することで、抗生物質を薬用することなく（副作用に悩まされること無く）ヘルペスウイルスを上手く抑え込むことができます。

ちなみに、
ヘルペスウイルスは人間の体内から消滅させることはできません（２００７年７月現在）
これは、現在科学や医学ではできないらしいのです。

ヘルペスが治るなどは間違いで、ヘルペスウイルスを抑え込むという表現になります。
疲れやストレスによって肌に出てくる唇ヘルペスや性器ヘルペスを抗生物質で一時的に治すと、
その後もっと抗生物質が必要になりますよね（これは、抗生物質の一般的基本知識です）
抗生物質に頼らないハーブ生活を、アボリジニは昔から営んでいるわけです。

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Citral has several medicinal uses. It is a potent antiseptic and may prove useful in treating gastro-intestinal infections, including Helicobacter pylori, which is responsible for many cases of gastric ulcer. It has antispasmodic properties that help alleviate intestinal spasms, as may occur with intestinal infections or adverse reactions to foods. Overall, it has a relaxing effect. Further, one of its modern applications is for treating throat disorders, either due to infection or to overuse and irritation.
↑
あああ、医学用語多すぎて私の英語力では難しいです…
どなたか、教えてくださいませ～
そのうち、がんばって直訳…してみます。
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これ以上に詳しい情報は無いかもしれない、相当優良な情報です。
元情報サイトはこちら（ドイツのサイト）

[Citral]
Occurrence and application
Citral is seldomly applied as fragrances in perfumes (22).

Citral has a strong lemon fragrance. The substance is applied as flavour additive in foodstuffs. Intake of the substance is estimated to be 6849 µg/person/d (114 µg/kg bw/d) in and 6990 µg/person/d (117 µg/kg bw/d) in the USA. In the USA, a little more than half of the substance is considered to originate from natural sources. (23).It occcurs in lemon grass in its natural form (19).

JECFA (Joint Expert Committee for Food Additives) has established a group-ADI (Acceptable Daily Intake) (through foodstuffs)) for citral, citronellol, geranyl acetate, linalool og linalyl acetate, of 0-0.5 mg/kg bw (calculated as citral) (25).

Identification
Citral is a terpenaldehyde. The substance is a mixture of the aldehydes geranial 55-70 % (trans-structure – the shown) and neral 35-45 % (cis-structure) (26).

Chemical name Citral
Synonym 3,7-Dimethyl-2,6-octadienal
CAS-No. 5392-40-5
EINECS No. 226-394-6
Molecular formula C10H16O
Molecular structure
Legislation:
Classification in accordance with the list of hazardous substances (Gov. order 439 of 3 June 2002) (12)
List of Undesirable Substances 2004 (16)
Cosmetics (1) Xi; R 43
Listed, as the substance is assessed to be allergenic at skin contact. and is 1 of th 26 fragrance allergens.assessed by SCCNFP.
Fragrances are declared in cosmetics if applied in quantities above 0.01% in products which are cleaned and 0.001% in products which are not cleaned.

Physical/Chemical properties

Physical state Liquid
Molecular weight (g/mol) 152.3 (19)
Melting point °C < -10 °C (24)
Boiling point, °C 226-228 °C (24)
Vapour pressure (Pa) < 130 Pa ved 100 °C (24)
Octanol/water partition coefficient (log Pow) 2.8 for neral og 3.0 for geranial ved 25 °C (24)
Water solubility (mg/L) 590 mg/L ved 25 °C (24)

WHO has established a NOEL[9] for citral of 100 mg/kg bw/d for rats (25).

7.3.1.1 Acute toxicity
The LD50-value by oral administration of citral in rats was found to be 4960 mg/kg bw (26)

WHO has found that citral metabolises to harmless substances that are quickly excreted quickly through the kidneys (25), (26)

The dermal LD50-value for rabbits was found to be 2250 mg/kg bw (26).

7.3.1.2 Local irritation
Testing in rabbits showed that citral was found skin irritating, but not eye irritating (26).

7.3.1.3 Allergy
EU Scientific Committe (SCCP) has registered citral on the list of fragrances. The fragrances on the list are well known allergens. Many cases of allergy in consumers have been reported. In two described studies 4 of 228 patients (1.7%) and 19 of 1855 patients (1%) respectively showed allergic reactions to citral (18).

Citral was found strongly sensitizing in guinea pigs. Between 12 and 64% voluntary test persons were sensitized using the Human Maximization Test in humans (18).

Citral belongs to fragrances which should no be used separately but only in mixtures with substances depressing the sensitizing effect of the substance (22). IFRA (International Frangrance Association) recommends that citral is only applied in products together with substances preventing a sensitizing effect, for example 25% d-limonenee, mixed citrus terpenes eller a-pinenes (22).

7.3.1.4 Long-term, repeated exposure
Citral in micro encapsulated form was administered 3 groups of 10 rats of each sex in their daily diet during 14 weeks, the daily dose being 345, 820 and 1785 mg/kg bw for males and 335, 675, and 1130 mg/kg bw for females. All doses showed effects on kidneys in males. In females, the highest dose showed low increase and reduction of the bone marrow. In this study, a NOEL2 was found to be lower than 345 mg/kg bw/d for male rats. In female rats, NOEL was 645 mg/kg bw (25).

A 2-year study group of 50 rats of each sex was exposed through their diet to 0, 50, 10 and 210 mg/kg/bw/d. In the male group was found a dose-dependent increase of the mineralization of the kidneys, which was interpreted as an increase of normally occurring deviation in the rat strain. In this study, NOEL for citral was 100 mg/kg bw/d due to reduced increase in female rats at highest dose. There was no indication that citral is carcinogenic in rats (25).

Many studies with long-term repeated exposure in rats were performed, but the studies referred are the latest and were performed by NTP (National Toxicology Program) in the USA. Their laboratories are considered to be very reliable.

Citral has been tested in an Ames’ test and in a number of other tests with bacteria and mammal cells. It has also been tested for genotoxic properties after administration in living mice. Almost all results were negative (25)

Daily doses of citral of until 1000 mg/kg bw/day before, during and after mating did not effect the fertility of rats. In the high dose analyses, microscopy showed changes in the stomach of the experimental animals. The embryos showed reduced growth in the period of lactation (26).

A concentration of 423 mg citral/ m3 inspirated air resulted in reduced growth and abortation and death among pregnant female rats exposed for 6 hours/d on the 6-15 day of gestation, but was not teratogenetic (26).

Critical effect

The critical effect of citral is assessed to be contactallergy. Because of the allergenic potential of citral, humans allergenic to the substance should avoid skin contact, as there is no lower limit for this adverse effect.

No lower limit for the contactallergy is known. MoS[10]-calculation is based on effects other than allergy. The below calculation is based on NOEL for 2 years:

Table 8-3 . Summary of data used for calculation of MoS for citral

Toxicological data (animals)
LD50, (mg/kg bw), oral, rat 4960 (24)
NOEL, (mg/kg bw/d), intake (2 year), rat 100 (23)
LOEL, (mg/kg bw/d), intak (14 weeks), rat 345 (23)

[Citronellol]
7.4.1.1 Occurrence and application
Citronellol is applied as perfumery material in perfumes, often in flower fragrancies. The substance is also applied as a flavour additive in foodstuffs. Intake of the substance is estimated to be 370 µg/person/d (6,2 µg/kg bw/d) in Europe and 771 µg/person/d (13 µg/kg bw/d) in the USA, Much of this originates from natural ingredients in foodstuffs (23). Citronellol also occurs in rose- and geranium oil and as gland secretion in alligators. (19).

Identifikation
Citronellol består af en terpenalkohol.

Chemical name Citronellol
Synonyms 3,7-Dimethyl-6-octen-1-ol, dl-Citronellol
CAS-No. 106-22-9
EINECS No. 203-375-0
Molecular formula C10H20O
Molecular structure
Legislation:
Classification in accordance with the list of hazardous substances (Gov. order 439 of 3 June 2002) (12)
List of Undesirable Substances 2004 (16)
Cosmetics (14) Not classified
Listed, as the substance is assessed to be allergenic at skin contact.
The fragrance is stated on the product label of cosmetics if applied in quantities above 0.01% in products which are cleaned and 0.001% in products which are not cleaned.

Physical-chemical properties

Physical state: Liquid
Molecular weight (g/mol) 156.3 (19)
Melting point °C No information
Boiling point, °C No information
Vapopour pressure (Pa) No information
Octanol/water partition coefficient (log Pow) No information
Water solubility (mg/L) No information

WHO har established a NOEL[11] for citronellol of > 51 mg/kg bw/d for male rats (25).

JEFCA (Joint Expert Committee for Food Additives) has established a group-ADI (Acceptable Daily Intake) of 0-0.5 mg/kg bw/d expressed as citral for the group of terpene-containing flavour additives (citral, geranylacetate, citronellol, linalool and linalyl acetate) (1).

Acute toxicity
LD50-values at oral administration of citronellol in rats were found to be 3450 mg/kg bw (21), (25) and 5000 mg/kg bw (21).

WHO assessed that citronellol most likely metabolises to harmless substances based on data on a corresponding substance (geraniol). The end product is excretred through the urine (25).

The LD50-value of citronellol applied on the skin of rabbits was found to be 2650 mg/kg bw (21).

Local irritation
The effect of citronellol is moderately irritating to the skin of humans for 48 timer, and seriously irritating to the skin of rabbit and guinea pig for 24 hours (21). No information was found on eye irritation.

Allergy
The Scientific Committe of EU SCCP has registered Cinnamal on the list of fragrances. The fragrances on the list are well known allergens, on which, however, not many cases on allergy in consumers are reported. Two out of 20 perfume allergy sufferers (35%) and 2 out of 119 (1.7%) patients suffering from cosmetic allergy showed allergic reactions to citronellol (18).

Long-term, repeated exposure
10 rats of each sex were administered citronellol (mixed with equal parts of linalool) in the diet daily for 12 weeks. The doses were 51 mg/kg bw/d for males and 56 mg/kg bw for females. At this concentration, no effects on kidneys, liver, blood were found differing from the control group or from the normal area. In this study, NOEL for citronellel was found to be higher than 51 and 56 mg/kg bw in male and female rats respectively) (25).

The result of an Ames’ test and another bacterium test with Citronellol was negative (25).

TCLo[12] for citronellol for rats was found to be 1.3 mg/m³ air by inhalation for 4 hours. By repeated inhalation for 4 hours daily for 3 days, TCLo decreased to 0.3 mg/m³ air. In both analyses, the rats showed behavioural changes (21).

Critical effect

The critical effect of citronellol is assessed to be contactallergy. Because of the allergenic potential of citronellol, humans allergic to the substance should avoid skin contact, as there is no lower limit for this adverse effect.

No lower limit for the contactallergy is known. MoS[13]-calculation is based on effects other than allergy. The below calculation is based on NOEL from the above study with administration of rats for 12 weeks.

Table 7-4 Summary of data used for calculation of MoS for citronellol

Toxicological data (animals)
LD50, (mg/kg bw), oral, rat 3450 (19,23)
NOEL, (mg/kg bw/d), intake, male rat > 51 (23)