Fluoride and Silicon Content of Foods from Normal and Endemic Fluorotic Areas in India

• Published in: Journal of food composition and analysis 1997-03, Vol.10 (1), p.43-48
• Main Authors: Anasuya, A., Bapurao, S., Paranjape, P.K.
• Format: Article
• Language: English
• Subjects: ANDHRA PRADESH; ARROZ; Biological and medical sciences; COMPOSICION APROXIMADA; COMPOSITION GLOBALE; CONTENIDO MINERAL; ELEUSINE CORACANA; FLUORIDES; FLUORURE; FLUORUROS; FOOD COMPOSITION; Food toxicology; GEOGRAPHICAL VARIATION; Medical sciences; MINERAL CONTENT; PENNISETUM GLAUCUM; PROXIMATE COMPOSITION; RAGI; RICE; RIZ; SILICIO; SILICIUM; SILICON; SORGHUM; TENEUR EN ELEMENTS MINERAUX; Toxicology
• ISSN: 0889-1575; 1096-0481
• DOI: 10.1006/jfca.1996.0516

Samples of rice (Oryza sativa, n= 36), sorghum (Sorghum vulgare, n= 19), and bajra (Pennisetum typhoideum, n= 18) were collected from normal and endemic fluorotic areas located in the state of Andhra Pradesh, India. Samples of ragi (Eleusine coracana, n= 5), which were available only in a normal area, were also obtained. Fluoride and silicon content of these foods was measured. The concentrations (means ± SD) of fluoride and silicon in the above foods, expressed as mg/kg, are as follows. Of the cereals and millets from normal areas, ragi contained the highest concentration of both fluoride (0.8 ± 0.41) and silicon (2000 ± 500). Fluoride levels were similar in rice (0.16 ± 0.05), sorghum (0.15 ± 0.04), and bajra (0.20 ± 0.09). Silicon contents of sorghum (300 ± 290) and bajra (400 ± 110) were significantly higher than that of rice (90 ± 31) and lower than that of ragi (2000 ± 500). Between bajra and sorghum, the former contained significantly higher levels of silicon. Samples of rice and sorghum grown and consumed in the fluorotic area had significantly higher (P< 0.02 andP< 0.001) concentration of fluoride than those collected from the normal area. The values were 0.4 ± 0.32 in rice and 0.4 ± 0.16 in sorghum from the fluorotic area and 0.16 ± 0.05 in rice and 0.15 ± 0.04 in sorghum from the normal area. Silicon contents of rice and bajra (mg/kg) grown in the fluorotic area were 200 ± 150 and 600 ± 240, respectively. These values were significantly higher (P< 0.02,P< 0.01) than those present in the respective foods from the normal area (90 ± 31 in rice, 300 ± 290 in sorghum). No significant difference was observed in silicon levels of sorghum from normal (300 ± 290) and fluorotic (300 ± 130) areas although an increasing trend was observed in the latter area. Three important findings emerge out of this study: (1) Silicon-rich food grains of common use in India are ragi, sorghum, and bajra. (2) Foods grown in fluorotic areas in general contain not only higher concentration of fluoride,but also silicon,an element which was found to aggravate the risk of fluorosis in experimental animals. (3) Compared to the other cereals studied, ragi contains significantly higher levels of both silicon and fluoride.