A study of Bacterial Contamination of Ghanaian Currency Notes in Circulation

Abstract

The study aimed at determining the presence, type and nature of bacterial contamination of Ghanaian currency notes in circulation. One hundred currency notes of different denominations were randomly collected from sellers on the major streets and markets of the Cape Coast Metropolis into sterile paper bags, shaken in universal bottles with 10ml sterile buffered peptone water, removed and the resulting peptone water incubated overnight and later sub-cultured onto Blood agar, MacConkey, Cysteine Lactose Electrolyte Deficient (CLED) and incubated at 370C for 24hours. Colonial Morphology, Gram Reactions and Biochemical tests were used for identification of isolates. All 100 samples collected were contaminated with one or more bacteria representing 100% contamination. A total of 107 bacteria isolates were obtained from the 100 samples made up of 13 different bacteria species. Bacteria isolated from the notes include Coagulase negative Staphylococci (23.4%), Staphylococci aureus (8.4%), Escherichia coli(5.6%), Bacillus species (23.4%), Klebsiella species (5.6%), Enterobacter species (2.8%), Enterococci species (10.3%), and Proteus species (8.4%) among others. The One Ghana Cedi and Twenty Ghana Cedi notes had more bacteria isolated than their number sampled (43 out of 40) and (25 out of 20) respectively. Although the number of species isolated increased with sample numbers, all the denominations were contaminated with Coagulase Negative Staphylococci and Bacillus species. Four non-circulated notes of each denomination used as controls had no bacteria growth. This work seeks to confirm bacterial contamination of everyday currency and also introduces the nature and levels of contamination of the Ghanaian currency.