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GermsonBanknotes
Peopleindifferentcountriesusedifferenttypesof 1 yuaninChina, pesosinMexico, poundsintheUnitedKingdom, dollarsintheUnitedStates, AustraliaandNewZealand. Theymayuse 2 currencies, butthesecountries, andprobablyallcountries, stillhaveonethingincommon1: Germsonthebanknotes.
Scientistshavebeenstudyingthegermsonmoneyforwellover2 100 years. Attheturnofthe 20th 3 , someresearchersbegantosuspectthatgermslivingonmoneycouldspreaddisease.
Moststudiesofgermymoneyhavelookedatthegermsonthecurrency 4 onecountry. Inanewstudy, FrankVriesekoop3 andotherresearcherscomparedthegermpopulationsfoundonbillsofdifferent 5 .
Vriesekoop3 isamicrobiologistattheUniversityofBallaratinAustralia4. Heledthestudy, whichcomparedthegermpopulationsfoundonmoney 6 from 10 nations. Thescientistsstudied 1,280 banknotesintotal; allcamefromplaceswherepeoplebuyfood, likesupermarketsstreetvendorsandcafes, 7 thosebusinessesoftenrelyoncash.
Overall, theAustraliandollarshostedthefewestlivebacteria ---- nomorethan 10 persquarecentimeter. Chineseyuanhadthemost ---- about 100 persquarecentimeter. Mostofthegermsonmoneyprobablywouldnotcauseharm.
Whatwecallpapermoneyusuallyisntmadefrompaper. TheU. S. dollar, forexample, isprintedonfabricthatismostly 8 .Differentcountriesmayusedifferent 9 toprinttheirmoney. SomeofthecurrenciesstudiedbyVriesekoopandhis 10 suchastheAmericandollarweremadefromcotton. Othersweremadefrompolymers.
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