Quantitative Analysis of Chemical Contaminants in Ghanaian Herbal Alcoholic Bitters

摘要

Ten popular Ghanaian herbal alcoholic bitters were selected for the investigation of organic and inorganic chemical contaminants using a combination of LR/EI-GCMS, HR/ESI-LCMS, ICP-AES and AAS techniques. The ability of these drinks to inhibit microbial growth and the effects of shelf-life on the physicochemical parameter pH were also studied. The results showed that, Ghanaian herbal alcoholic bitters have a complex matrix of various compounds which are difficult to isolate. Di-n-octyl phthalate (DOP) was present in all the ten herbal alcoholic bitters studied but the amounts of DOP isolated from the five drinks studied into detail were 7.84mg/L, for MD, 12.53mg/L, for KA, 30.72mg/L, for HA, 36.22mg/L for AG and 15.76mg/L for OG. The level of DOP in all the samples exceeded by a large amount the WHO limit of 8ug/L. The herbal alcoholic bitters, as packaged did not inhibit the growth of pathogenic bacteria strains Staphylococcus aureus and Escherichia coli. With the rich organic load per bottle and the fact that these drinks were found to be generally acidic, microbial invasion and growth is highly possible. The potential to further complicate the chemistry of these products when microbes metabolize the complex organic compounds in the drinks can lead to microbial toxicity in addition to direct pathogenic effects. The ten Ghanaian herbal alcoholic drinks analyzed generally contained various metals at different levels compared to the WHO permissible limits. The levels of the trace metals Al and Fe in all the herbal alcoholic drinks exceeded the WHO recommended daily intake (RDI) of 0.2mg/L and 15mg/L respectively. The levels of As exceeded the WHO RDI of 0.01mg/L in all the drinks except in PB, OG and CL. However, levels of Hg, Cd, Se and Pb were below detectable limits for all the drinks studied. We hope that this data will be applied to the continued study of this problem in more depth and to allow this to inform a policy process that will lead to greater quality assurance of these drinks and safeguard the health of Ghanaian consumers.