Dissolution of aluminium from sub-standard utensils under high fluoride stress: A possible risk factor for Chronic renal failure in the North-Central Province

Abstract

Chronic renal failure of an endemic nature and unknown aetiology affects people in the North-Central Province of Sri Lanka. People affected, consume fluoride rich water and almost exclusively use sub-standard aluminium pots for cooking and storing water. Leaching of aluminium under different fluoride stress and under the acidic conditions used in cooking was studied. Aluminium was -determined using a graphite furnace Atomic Absorption Spectrophotometer. In the absence of acidic spices, the amount of aluminium leached was quite small with a maximum of 1.20 ppm reached after 10 min of boiling in 6 ppm fluoride solution. However, under acidic conditions obtained during the use of tamarind at a pH of 3.02, the aluminium leached was around 18 ppm even in the absence of fluoride with a regular enhancement of leaching at higher fluoride levels. The aluminium leached at 6 ppm fluoride reached 29 ppm after 10 min of boiling. Similarly, at a pH of 2.12 in the presence of 0.1 M tartaric acid, the maximum aluminium concentration leached reached ca. 50 ppm. Aluminofluoride complexes may play a significant role in causing chronic renal failure.