Problems and challenges in the detection of essential oil adulteration – a review of current analytical methods

Oliwia Szambora; Katarzyna Paradowska

doi:10.56782/pps.880

Published : 2026-08-23

Vol. 24 No. 3 (2026)

Problems and challenges in the detection of essential oil adulteration – a review of current analytical methods

Oliwia Szambora

Katarzyna Paradowska

DOI: https://doi.org/10.56782/pps.880

Abstract

Essential oils are volatile, aromatic plant metabolites with a complex chemical composition and a wide range of applications in the pharmaceutical, cosmetic, and food industries. Due to their high market value and the limited availability of certain raw materials, essential oils are susceptible to numerous forms of adulteration, such as dilution with cheaper substances, the addition of synthetic compounds, or substitution of the botanical source. Quality control and authenticity assessment of essential oils require advanced analytical methods. The European Pharmacopoeia recommends basic physicochemical determinations, including relative density and refractive index. Gas chromatography coupled with mass spectrometry (GC–MS) represents the gold standard for the analysis of volatile constituents of essential oils, enabling both identification and quantitative evaluation of terpene compounds. High-performance liquid chromatography (HPLC) allows for the determination of non-volatile and thermolabile compounds, which is particularly important in citrus oils. Nuclear magnetic resonance (NMR) spectroscopy offers a rapid, non-destructive method for authenticity verification and impurity detection, despite its lower sensitivity compared to chromatographic techniques. Contemporary approaches to essential oil quality control are based on the combination of complementary analytical techniques, enabling comprehensive chemical characterization and effective detection of adulteration.

Keywords:

essential oils, quality control, GC–MS, HPLC, NMR

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Szambora, O., & Paradowska, K. (2026). Problems and challenges in the detection of essential oil adulteration – a review of current analytical methods. Prospects in Pharmaceutical Sciences, 24(3), 45–53. https://doi.org/10.56782/pps.880

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Oliwia Szambora

oliwiaszambora@gmail.com

Affiliation:

a:1:{s:5:"en_US";s:28:"Medical University of Warsaw";} Poland

Katarzyna Paradowska

katarzyna.paradowska@wum.edu.pl

Affiliation:

Medical University of Warsaw Poland

Bio Statement (e.g., department and rank)

Department of Organic and Physical Chemistry, Faculty of Pharmacy

Problems and challenges in the detection of essential oil adulteration – a review of current analytical methods

Oliwia Szambora

Katarzyna Paradowska

Abstract

Keywords:

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