我们知道,钞票因为流通频繁,上面的细菌非常多,对于爱干净的人来说,摸完钞票立刻洗手是必须的。而在一些非法交易中,钞票也常常被称为“脏钱”。这不禁让我们的脑子中产生了问号:世界上最干净的钱在哪里?在日本!2009年,美国科学家做了一个全球纸币上沾染古柯碱(Cocaine,毒品的一种)的调查,发现多达九成的美钞都沾有古柯碱,其中以首都华盛顿的美钞最为肮脏。在这种意义上,中国和日本的钞票则“干净”得多,只有一成至二成沾有古柯碱。 We know that because of the frequent circulation of banknotes, there are so many bacteria on them that it is necessary for people who love cleanliness to wash their hands immediately after they have taken the money. In some illegal transactions, banknotes are often called “dirty money.” This can not help but give rise to a question mark in our minds: Where is the cleanest money in the world? In 2009, a U.S. scientist who did a survey of Cocaine (a type of drug) on ​​global paper currency found that Up to 90% of the U.S. dollar bills are stained with coca-cola, with the U.S. dollar being the most filthy in the capital, Washington. In this sense, the bills in China and Japan are much cleaner and only 10% to 20% have cocaine.