INFLUENCE OF AN ANTIOXIDANT ON THE FORMATION OF ALLERGENIC COMPOUNDS DURING AUTOXIDATION OF D-LIMONENE

Butylated hydroxytoluene (BHT), a common anti-oxidant, was added to different samples of d-limonene. The decrease in concentration of d-limonene and the formation of oxidation products were compared between the samples and with samples without anti-oxidant using gas chromatography. The aim of the study was to investigate how long d-limonene to which BHT was added could be handled when air-exposed at room temperature, without formation of oxidation products which according to previous studies increase the risk of skin sensitization. In experiments trying to mimic the handling of limonene products at workplaces the addition of BHT prevented auto-oxidation for periods depending on the purity of the products and on the room temperature. Cold and dark storage of d-limonene in closed vessels prevented auto-oxidation for 1 year without addition of anti-oxidant.