Fluoride Action Network

Tanzania: Seminar on ‘Roasted Teeth’ in Arusha

Source: The Arusha Times | April 20th, 2013 | By Ramadhani Kupaza
Location: Tanzania

A worried parent who has just relocated to Arusha has asked seminar organizers if her child will acquire “roasted teeth” by drinking water in Arusha. The parent has learned that a substance called fluoride which is present in most of the natural water in Arusha causes teeth to appear as if they have been roasted. The Nelson Mandela African Institute of science and Technology and the University of Sassari in Italy organized the seminar.

The seminar organizers informed the worried parent that they will analyze the water that members of her family drink to determine whether the concentration of fluoride in that water causes teeth to appear as if they have been roasted.

The presenter on the subject informed seminar participants that there are two references for determining acceptable concentration levels of fluoride in drinking water. He mentioned that the World Health Organization (WHO) has set the internationally acceptable concentration level while each country sets acceptable concentration levels independently. For example, the WHO fluoride concentration standard is 1.5mg / liter while Tanzania accepts 4mg / liter. That is a national standard improvement from 8mg/ liter used before 2009.

By the way, fluoride affects bones as well as teeth. Scientists use the word sclerosis to refer to the effect of fluoride on teeth and bones. Seminar participants asked if fluoride affects animals other than humans. They asked if the vegetables cultivated in areas which are contaminated with fluoride contain harmful concentrations of the substance. The presenter did not respond to such questions adequately because the aim of the presentation was to express a multidisciplinary approach to understand availability and movement of safe underground water in the Mount Meru ecosystem which is located in the East African Rift Valley in Arusha. It is necessary to develop multidisciplinary study approaches to determine sites that can provide safe groundwater in Arusha because volcanic activities in the area have complicated the rock systems or rather aquifers that hold underground water. In addition, underground water in volcanic areas tends to contain high levels of fluoride.

In the end the presenter informed participants that the multidisciplinary study approach has led to mapping of a hydrological system in Arumeru District that can be used for locating suitable sites for drilling safe underground water. The presenter explained further that two boreholes have been drilled in the area to verify accuracy of the hydrological map.

The fluoride content of one of the two boreholes that were drilled in the area provided water containing fluoride levels that are acceptable based on Tanzania standards. The borehole produces substantial quantities of water. It means that the multidisciplinary study has been able to locate accurately suitable sites for drilling safe drinking water.

The second borehole has been drilled at King’ori junction in Meru District. The water in the borehole contains 2.2mg/liter of fluoride. The quantity of water in the borehole is also substantial. Again, it means that the studies have established a reliable map for locating suitable sites for good and substantial quantities of quality underground water in Meru District.

But it was not always smooth. The study has once recommended drilling of 80 meters at a site where there was no single drop of water even after drilling 120 meters deep in the ground. Some people joke about the miss that geology is an art rather than science.

Scientists applied a multidisciplinary research effort to map the underground safe water movements and availability in the area. The efforts include geological and Hydro-geological investigations. Others are hydro-chemical, geophysical and hydrological assessments.

In particular, scientists used specialized laboratories to analyze data from the studies. They used remote sensing laboratories and those that measure age of water in order to determine if the water storage underneath is recharged or it is stagnant water of the past. The scientists also used laboratories that analyze mineral compositions, conductivity of soil profiles and permeability of rocks in the area. Not to forget the use of laboratories to analyze fluoride contents of the water. The findings of the study promise that residents of Arusha may not have to worry about “roasted teeth” in the future.