Evaluation of Two Spectroscopic Techniques to Estimate the MDMA Dose of Ecstasy-Like Tablets, an On-Site Approach.

Portable near-infrared (NIR) and Fourier-transform-infrared (FT-IR) spectroscopy, combined with chemometric modeling, can reliably estimate the MDMA dose in seized tablets. When tested on 98 tablets, NIR achieved an R² of 0.64 (indirect contact, intact tablets) and 0.87 (direct contact, homogenized tablets) with RMSEP values of 8.0 and 5.9, respectively; FT-IR achieved an R² of 0.84 with an RMSEP of 5.4, compared to reference gas chromatography results. Both techniques are suitable for rapid on-site application, but dose estimation alone does not address all health risks—low-dosed substances, combinations with other drugs, and alcohol also matter, so laboratory analysis remains essential for comprehensive safety assessment.

Study at a glance

Abstract

MDMA, commonly known as "ecstasy," is widely used in clubs and at festivals, earning its reputation as a "party drug." The increasing demand for rapid on-site dose estimation of MDMA in tablets arises from the need of various stakeholders, including law enforcement, emergency services, and public health officials, to respond appropriately to potential public safety risks and incidents. This study evaluates the performance of two portable spectroscopic techniques (near-infrared [NIR] and Fourier-transform-infrared [FT-IR]) combined with chemometric modelling for estimating the MDMA dose in tablets. Ninety-eight seized tablets were measured on-site with both spectroscopic techniques and confirmed by the reference techniques: gas chromatography (GC) combined with a mass spectrometer (MS) and a flame-ionization detector (FID). Considering the correlation values (NIR: R2 = 0.64 for indirect contact with intact tablets, 0.87 for direct contact with homogenized tablets; FT-IR: R2 = 0.84) and the RMSEP values (NIR: 8.0 for indirect contact with intact tablets, 5.9 for direct contact with homogenized tablets; FT-IR: 5.4), both spectroscopic techniques provide a reliable dose prediction in comparison to the GC-FID results. Moreover, these devices are suitable for rapid on-site application. The instruments' choice depends on several factors, such as speed, safety measures, and laboratory support for modelling. However, determining the MDMA dose does not address all health risks. Other factors, such as the presence of low-dosed substances (undetectable on-site) and the combination of MDMA with other drugs and/or alcohol also play a significant role. Therefore, laboratory analysis remains essential for comprehensive safety assessment.