After doing some research, I found out some of the stages the water goes through in the filtering Process as the user sucks up the water in the straw.
It would be hard for me to criticize this straw that I have never used before. I did see it in the 'Designing for the other 90%' Exhibition at the Cooper Hewitt, and it seemed quite light and simple. It really amazed me that this simple object could really improve the lives of so many humans around the world.
From the information I have collected, and as shown in the diagram, it seems that the water goes through 4 stages of filtration. The first is a mesh that filters dirt, second is a polyester filter (interesting.. why polyester.. is there nothing else that can be used instead? isnt it slightly poisonous?) that filters out bacteria. Following is a chamber of beeds that kills 99.3% of bacteria and viruses. This i honestly do not understand. It would be interesting to know how small these beeds are and how it actually works. this is still a mystery to me. The next is a Granulated Active Carbon, which improves taste, smell and again filters. This stage is also a bit unclear to me. It would be interesting to further look into that.