VISOCOLOR® ECO Fluoride: Photometric determination of fluoride. Features: • Photometric determination of fluoride with 1,8-dihydroxy-2-(4-sulfophenylazo)naphthalene-3,6-disulfonic acid (SPADNS) with the photometer PF-12. • The test is delivered without color scale and can be evaluated only with the photometers PF-12! • Normally, the content of fluoride in surface and ground water is lower than 1 mg/l. • Permanent consumption of water containing more than 2 mg/l fluoride can cause a drinking water fluorese (a stained discolouration of the tooth enamel). • On the other hand a content of fluoride lower than 0.5 mg/l could lead to an increasing risk of caries. • The optimal content of fluoride in drinking water is about 1 mg/l. • To avoid problems with caries in some countries the content of fluoride in drinking water is artificially increased. • However, WHO and EC drinking water regulations recommend a threshold value of 1.5 mg/l F–. • In some European countries, the threshold value for mineral water is also 1.5 mg/l F–. • For the suitability of water for the preparation of baby food a threshold value of 0.7 mg/l F– is recommended. • Natural mineral waters with a fluoride content of more than 5 mg/l must be labelled with a warning. Specifications: • Type: photometric test kit • Range: 0.1 – 2.0 mg/l F– • Sufficient for: 150 determinations • Shelf life at least: 1.5 years • Sea water suitability: yes, after distillation • Detectable with PF-12: yes