Chemical profiles of tea tree essential oil samples available on the Bulgarian market

Melaleuca alternifolia Cheel (Myrtaceae), indigenous to Australia, is considered one of the tea tree essential oil (EO) sources, which have seen increased global utilisation. The EO is available in both its pure form and as an active ingredient in various commercial products. It is recognised for its safety, natural composition, and efficacy. This study aims to evaluate whether tea tree EOs available in Bulgarian markets meet established standards. Commercial EO products were randomly chosen from the Bulgarian market and analysed using gas chromatography-mass spectrometry. The analysis revealed that all samples were predominantly composed of monoterpenes and sesquiterpenes, with terpinen-4-ol as the major constituent. Other significant compounds included γ -terpinene, eucalyptol, α -terpineol, and terpinolene. All commercial products examined contained the requisite chemical compounds, indicating compliance with the necessary standards, except for one sample, which did not meet the required percentage criteria.