Many countries in the world today lack clean drinking water. In some countries, daily drinking water is brought directly from rivers. Some scientists in the United States developed a book that can be used to filter water for the public welfare organization Waterislife, called the "drinkable book". It can filter out bacterial impurities in the water, allowing some countries with water pollution to Drink clean water. Each page of the book introduces how to filter water and some basic hygiene knowledge. After people study, they can tear off the page and use it to filter clean drinking water. The filtered water can basically It meets North American drinking water standards. The nano-silver on the surface can kill most bacteria, and the filtered water volume of each page reaches 100 liters.
