Each page, costing just pennies to make, is coated with silver nanoparticles that, when used to filter water, can trap a reported 99.99% of the bacteria found in cholera, E. coli, and typhoid. One book is said to give 5,000 litres (up to four years) of clean drinking water for a single person.
Step 1: tear out a pre-perforated page — each will filter 100 litres of water
Step 2: slot the page into the base of the custom filter box
Step 3: replace the pressure plate and pour water through
Tests took place earlier this year in the remote mountain village of San José el Negrito, Honduras. Source water from a village tap, (above left) shows dark blue dots that are E. coli bacteria, and the water filtered through the page paper (above right) is bacteria free.
Focus group discussion in San José el Negrito, Honduras
Last month saw the beginning of pilot scale field testing in South Africa’s Western Cape, conducted by Folia Water, the company co-founded by scientist and inventor Teri Dankovich. The team gave filters to children at a rural primary school, then visited their families at home to find out what they can improve to give each family more power over their health and water quality.
The filter holders stacked in the photo below were industrially produced for the pilot test. The advantage over the filter box shown in photos earlier in the post is that the holders can be widely used with common household water containers (2-litre bottles, jerry cans, etc.).
Round pages are a better fit for the filter holders, so the book shape has changed (shown below, named the Safe Water Book). If it works, it saves lives. That counts immeasurably more than any design polish.
Teri Dankovich preparing for trials in the Western Cape
Let’s hope the South African trials are a success. Much respect to you and your team, Teri.