Sari Cloth Micrographs
Images: (1) new sari cloth micrograph (2) old sari cloth micrograph
Caption: An old sari cloth, available even in the poorest household, can be folded eight to ten times. This creates a 20-micron mesh filter, as we determined by electron microscopy.
The pictures show why old sari cloth, not new, is preferredóbecause its holes are smaller. Recent studies in Bangladesh show that sari filtering reduced cholera in villages by more than 50%.
Source: Dr. Rita Colwell, Director of The National Science Foundation