Analysis of Methanol and Ethanol Content in Illegal Alcoholic Beverages using Headspace Gas Chromatography: Case Studies at Rwanda Forensic Institute

Abstract

Illegal alcoholic production in Rwanda has become a critical social concern due to its widespread prevalence and associated health risks, stemming from the inexpensive distillation process employed by illicit producers. This often results in the unintentional production of toxic methanol instead of safe ethyl alcohol, presenting a substantial hazard in the context of illegal alcohol production. Methanol, when consumed, transforms into toxic formic acid in the body, causing severe health complications by disrupting mitochondrial respiration. Between 2021 and 2022, 183 forensic cases related to methanol and ethanol poisoning were collected nationwide and examined at the Rwanda Forensic Institute (RFI). Utilizing Headspace Gas Chromatography, the study aimed to quantitatively assess the extent of the problem and compare results to Rwanda’s allowable limits for methanol and ethanol in alcoholic beverages. The analysis demonstrated a significant variation in ethanol content (3.8% to 98.9% v v-1) and methanol levels (32% to 58.3% v v-1), with 6.6% of samples exceeding the methanol limit (0.5% v v-1) and 16.9% surpassing the ethanol limit (45% v v-1). The City of Kigali emerged as the primary contributor to non-compliance, notably associated with specific brands like K’bamba, African Buffalo, Merry Cane, Royal Castle, and unbranded alcoholic beverages. Importantly, none of the samples tested positive for both methanol and ethanol simultaneously, emphasizing the urgency of monitoring and regulating Rwanda’s alcoholic beverages market to ensure compliance with acceptable methanol and ethanol levels and safeguard public health.