2-3 years ago, 3 out of 10 people in the world have no access to the safe drinking water. The population of the world has increased so the situation has definitely got worst. In capitalism, every problem is actually a business opportunity. Sawyer S1 for example is a quick solution to get rid of water impurities but the real question is how can it be affordable for poor people of underdeveloped countries where situation is the worst?