Photo Toxicity In Bergamot Oil

Photosensitizers Bergamot oil

Introduction Photosensitive reactions have been recognized for thousands of years. In ancient Egypt, India, and Greece psoralencontaining plants extracts were combined with exposure to sunlight to trea t skin diseases. In 1897, reports of dermatitis following contact with parsnips and angelica came from both the United States and England, and in 1916, E. Freu nd observed characteristic hyperpigmented lesions that he attributed to eau d e cologne containing bergamot oil. Unfortunately, none of the authors recog nized the necessity of ultraviolet radiation (UVR) for the reaction. In 1938, H. Kuske showed that plant furocoumarins caused photosensitization, and shortly thereafter, T.Jensen and K. G. Hansen repo rted that UVR between 320 and 380 nm caused the reaction maximum.. In 1967, British researchers discovered that sandalwood oil in sunscreens and cosmetics caused photoallergies. Shortly thereafter, Frenc h scientists demonstrated that bergamot oil in sunscreens caused photosen sitivity disorders, and German researchers isolated photoreactive agents fr om colognes, perfumes, and oral contraceptives

Photosensitivity reactions Photosensitivity is an adverse cutaneous reaction that results when a certain chemical or dr ug is applied topically or taken systemically at the same time when a person is exposed to UVR or vi sible light . Photosensitivity reactions may be mor e specifically categorized as phototoxic or photoal lergic in nature. Phototoxicity is much more com mon than photoallergy

Photosensitizers photosensitizers are chemicals that induce a photoreaction. The chemicals may be therapeutic, cosmetic, industrial, or agricultural. Photosensitivity r eactions can be caused by injected, oral, or topically a pplied chemical photosensitizers. In most cases, the m echanism is phototoxicity like a bergamot oil, but som e agents cause photoallergy.

Bergamot oil Scientific Name: Citrus bergamia Common Name: Bergamot Oil Bergamot oil is cold-pressed from the peel of the nearly ripe fruit. The aroma of bergamot oil is fresh, lively, fruity and sweet. It is an excellent deodorizer. Aromatherapy benefits: uplifting, inspiring, confidence. Avoid using bergamot on the skin when there is a possibility of exposure to sunlight because it can cause phototoxicity.

Composition of Bergamot oil

Bergapten

Limonene

Linalyl acetate

alpha-Pinene

Linalool

Myrcene

How to evaluate the phototoxicity In vivo experiment Test Sample (bergamot oil) The test sample was inject into the patch tests (diameter of 10 mm) and was applied on the back skin areas.

It was exposed with irradiation (at a dose of 5 J/cm2,as measured in the UVA rang)

It was exposed with irradiation (as controlled)

Observed and recored every 24 h,48h,72h after exposure

How to evaluate the phototoxicity In vitro experiment 3D skin model tissues

It was pre-incubated in fresh medium for 1 h (37 o C,5%CO2) were applied with test sample overnight ( 16-20 h ) It was exposed with UV light

It was not exposed with UV light

(at a dose of 6 J/cm2, as measured in the UVA rang)

It was detected by spectrophotometer (at 540 nm)

Statistical analysis by the mean photo effect (MPE)

The MPE & MED The MPE (Mean Photo Effect ) MPE is a statistical comparison of the dose–response curves obtained with and without UV and a test substance is pr edicted as phototoxic •

if MPE is higher than 0.1 is predicted as ‘‘probably phototoxic’’ (OECD, 2004)

The MED (Minimal Erythema Dose ) MED is amount of sunlight needed to cause a minimally perceptible erythema sunburn. • MED quantifies the subject’ s actinic sensitivity is depend on subject’s

phototypes

Phototoxic in Bergamot oil

Hyperpigmented on streak on the dorsa of hand of a patient with bergapten phototoxicity

Skin irritation

Application of Cosmetic

Reference - Rūta Dubakienė, Miglė Kuprienė. Scientific problems of photosensitivity. Medicina (Kaunas) 2006; 42(8) - emedicine.medscape.com/article/1119063-media - www.elsevier.com/locate/toxinvit -http://www.sunadvise.com/?page_id=32 -http://books.google.co.th/books?id=2iCr7Xglyi4C&pg=PA192&lpg=PA192&dq=def inition+of+Minimal+erythema+dose&source=bl&ots=sz3at_cEx9&sig=LXHEiyoLR S57qcXULNMWuM47hhA&hl=th&ei=v1SzSuPgII_y6gOBzYz_CQ&sa=X&oi=boo k_result&ct=result&resnum=10#v=onepage&q=definition%20of%20Minimal%20eryt hema%20dose&f=false -สำำนักวิทยำศำสตร์เครื่องสำำอำง.เอกสำรประกอบกำรสอนเรือ่ ง photosensitive reaction & phototoxicity.