A high incidence of fluoride in drinking water leads to a crippling bone disease called skeletal fluorosis which has affected many people in some parts of India. The disease causes crippling deformities of the spine and joints, especially in children whose skeletons are still forming.

Now, a simple colour changing test is being developed to detect fluoride in drinking water which helps to prevent the disease. Lead researcher Simon Lewis from University of Bath in Britain states that while low amounts of fluoride are good for teeth and prevents tooth decay, high levels lead to weakened bones and crippling deformities.

As water passes over certain minerals, it can dissolve fluoride, which results in elevated levels of fluoride in drinking water. While in developed countries, water is routinely tested for fluoride and is monitored and controlled at treatment works, in developing countries, people rely on untreated water drawn from wells that can often contain high levels of fluoride.
A simple colour changing test has been developed which does not require a lab, power supply or trained operator. Researchers have developed a molecule that simply changes colour in few minute if fluoride content is higher than the recommended level.

Lewis said that they are in the process of developing this technology into test strips, similar to litmus paper, that allow people without any scientific training to perform a test that is low cost, rapid and robust.