Evaluation of the reliability of human teeth matrix used as a biomarker for fluoride environmental pollution.

Environmental contamination by heavy metals has been a matter of great concern in many countries for several decades. Human exposure to such elements may cause adverse health effects and young children are particularly at risk. Many matrixes have been used for determination of metal exposure levels. Hard tissues such as teeth and bones have some advantages compared to other matrix. Dental tissues are considered to be suitable for long-term metal exposure due to their stability, resistance to physical and chemical degradation and their good preservation over time. Several studies have analyzed the teeth of animals for assessment the relationship between increased fluoride exposure and dental fluorosis, however few studies have been conducted on human teeth. Thus, the aim of the present study was to assess the reliability of human teeth matrix used as a biomarker for fluoride environmental pollution in Tunisia, and to evaluate the relationship with place of residence, age, dental caries and sex. Teeth samples (n=123) were collected from individuals living in Gafsa (fluoride-polluted area which inhabitants are to a great extent exposed to heavy metals) and Tunis (non polluted area). Samples were analyzed using a potentiometric method. The fluoride concentration was found to be significantly higher in teeth from Gafsa samples than those from Tunis. Their control levels were respectively 6793.1µg/g and 1068.8µg/g. The results indicate that there is a clear relation between fluoride concentration and residence of living. An increased level of dental fluorosis in fluoridated communities has been used to evaluate historical chronic exposure to fluoride in these communities, despite constant fluoride levels in the drinking-water. The fluoride concentration was also observed to be significantly increased in polluted area with age and in carious teeth whereas, no significant difference was observed for sex. Our study confirms well that human teeth used as a bioindicator for environmental pollution provide good chronological information on exposure, and highlighted the risks incurred by consumers living in such polluted area.

[Creation and report of the Tunisian Fanconi Anemia Registry (TFAR)]. / Création et rapport du registre tunisien de l'anémie de Fanconi (TFAR).

INTRODUCTION: Fanconi anemia (FA) is a genetically and phenotypically heterogeneous inherited disease. Many groups have established FA registries. In Tunisia, in collaboration with the Tunisian Fanconi Anemia Study Group (TFASG), we set up the Tunisian Fanconi Anemia Registry (TFAR). PATIENTS AND METHODS: We contacted all hematology and pediatrics departments to include their FA patients diagnosed between January 1983 and December 2008. The registry is available on the TFASG web site (www.fanconi-tunisie.net). RESULTS: Sorting the files brought out 142 patients belonging to 118 families. The mean age at diagnosis was 11 years. There was consanguinity in 86%, malformative syndrome in 91%, and pancytopenia at diagnosis in 69%. Of 28 patients, 95% belonged to the FANCA group. Androgen treatment was given in 109 cases and genoidentical bone marrow transplantation (BMT) in 27 patients. The diagnosis of a myelodysplastic syndrome was retained in 4%, acute leukemia in 6%, and a solid tumor in 2%. The median overall survival time in all patients is 17 years 5 months; it is significantly better in patients having received allografts (p=0.01). CONCLUSION: FA seems frequent in Tunisia, which is in part explained by the high consanguinity and endogamy in this country. Hematologic impairment is still the most frequent revealing circumstance of the disease. It is often severe or moderate and requires androgen treatment or bone marrow transplantation. BMT should be proposed to all patients with an HLA-compatible donor.