Issues: This contribution aims to examine systematically the evidence on the impact of the quality of unrecorded alcohol products on health consequences.
Approach: Systematic computer assisted review of the literature.
Key findings: There are a number of pathways related to alcohol quality that may lead to acute or chronic health problems. The following constituents and contaminants of alcoholic beverages were identified as likely contributors to these problems: (i) toxic metals (e.g. lead) from contaminated water sources or unsuitable distillation equipment; (ii) volatile constituents, such as acetaldehyde or higher alcohols, which may be produced in significant amounts due to faults in production technology or microbiological spoilage; (iii) ethyl carbamate (urethane), a carcinogenic contaminant with major occurrence in certain fruit and sugarcane spirits; (iv) biologically active flavour compounds (e.g. coumarin in cosmetics used as non-beverage alcohol); (v) toxic compounds used to denature alcohol (e.g. methanol or diethyl phthalate). In addition, the often higher ethanol content may have detrimental health effects. These pathways should not be assumed as present for all subcategories of unrecorded alcohol, but are more relevant to certain types and geographic regions.
Implications: A health impact of unrecorded alcohol over and above the effect of ethanol cannot be excluded. More research is urgently needed, especially with respect to liver disease and alcohol poisoning as endpoints.
Conclusion: A feasible approach for new research on the effects of unrecorded alcohol could be based on a representative sample from low socioeconomic regions with high prevalence of unrecorded consumption.