Is filtering water through cotton effective against pathogens?

Cotton’s Porosity and Pathogens

Cotton’s ability to filter water is limited by its porosity. The diameter of cotton fibers typically ranges from 15 to 40 micrometers, allowing particles as small as 1-2 micrometers to pass through. However, this may not be sufficient to prevent the passage of more resilient pathogens like viruses (diameter 0.02-0.3 micrometers) or parasites like Giardia and Cryptosporidium, which can have diameters ranging from 8-15 micrometers.

Cotton as a Pre-Treatment Method

While cotton may not be effective as a standalone water filtration method, it can be used as a pre-treatment step to remove larger particulate matter and reduce the overall bacterial load. By using cotton to filter water, you may be able to remove up to 90% of bacteria and particulate matter before further treatment, making subsequent filtration methods more effective. This approach can be useful in emergency situations where access to more advanced filtration equipment is limited.