This snippet found in the Ghanaian national archives in Accra didn’t seem to warrant a full-blown research article, but I thought it was funny enough to transcribe.
A medical officer in colonial Gold Coast wrote an article titled “Filthy Lucre” for the colony’s 1920 annual report (ADM 5/1/77, PRAAD-Accra). He wrote that “the native African is often pocket-less and much given to using his mouth as a receptacle for all sorts of things,” a situation “fraught with serious pathological possibilities.” Sampling ten notes, the author found no evidence of “faecal pollution,” but he did identify a motley array of bacteria, molds, and yeasts. A few mites and mite eggs were also found. Despite these rather innocuous results, he wrote: “it can scarcely be questioned therefore that, given the opportunity, [paper notes] might convey the fungi of skin affections, the virus of exanthems normally spread by scales of desquamated skin, the eggs of intestinal parasites, the spores of pathologenic bacteria, and itch mites or other similar vermin. Many a ‘travelled shilling’ must meet with ample opportunity.”
A quick Google Scholar search shows plenty of recent research into “dirty money,” like this 2010 article: Tagoe et al., “A study of Bacterial Contamination of Ghanaian Currency Notes in Circulation.”
The contrast between crisp ATM notes and well-circulated small bills in Ghana is striking, and I’m not surprised that people are grossed out – but it’s definitely an aesthetic problem. Perhaps another reason to expect more mobile and e-currency adoption in the near future?