Johanna Rudbäck, a researcher at the University’s department of chemistry and molecular biology, says that despite EU safeguards, fragrances can develop allergenic properties after being exposed to the air.
Rudback’s thesis describes, for the first time, a test which can detect this potentially troubling problem.
The “simple and sensitive” method uses LC/ESI-MS/MS, a hyphenated mass spectrometry technique, in order to detect these compounds, which are likely to be capable of causing users to develop allergies.
In a statement from the University, Rudbäck commented: “I have developed methods for chemical analysis that for the first time make it possible to identify fragrance compounds that have been exposed to air, and thus become potent allergens in small amounts.”
Despite regulations, fragrances can still develop allergenic properties
EU regulations mean that fragrances may not include allergens exceeding 100ppm in ‘rinse off’ products and 10ppm in those designed to ‘stay on.’
However, the chemists’ research reveals that beauty products may still develop these allergy-causing substances.
In a paper in the Journal of Seperation Science on their new method, the team of researchers commented: “Products may still contain allergens, such as hydroperoxides, formed by oxidative degredation of their parent terpene.”
The four-person team, who published their research in March 2013, say that their method effectively deals with this problem: “The sensitivity and selectivity of the presented LC/MS/MS method enables detection of hydroperoxides from the fragrance terpenes linalool, linalyl acetate, and limonene.”
The chemists also noted that the method would require further validation for routine measurements.
Exposing fragrance compounds to the air
Rudbäck’s new procedure is built on research involving exposing the common fragrance compounds sweet orange oil and petitgrain oil to the air.
The researcher explained: “My analyses show that hydroperoxides from the fragrance compounds were present already before the bottles were opened, and the levels increased when the oils were exposed to air.”
With another experiment, which tested the common perfume compounds alpha-terpinene and citronellol, “the allergenic effect of both compounds increased tenfold after air exposure compared to the pure fragrance compounds,” the Gothenburg resident said.
Rudbäck also pointed out that the essential oils tested did not show any protection against the formation of allergenic compounds, making them vulnerable to developing damaging properties.