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The Drosophila melanogaster somatic mutation and recombination test (SMART) was used to assess the genotoxicity of surface (S) and bottom (B) water and sediment samples collected from Sites 1 and 2 on the Japaratuba River (Sergipe, Brazil), an area impacted by a petrochemical industrial complex that indirectly discharges treated effluent (produced water) into the river. The genotoxicity tests were performed in standard (ST) cross and high bioactivation (HB) cross flies and were conducted on samples taken in March (dry season) and in July (rainy season) of 2003. Mutant spot frequencies found in treatments with unprocessed water and sediment samples from the test sites were compared with the frequencies observed for similar samples taken from a clean reference site (the Jacarecica River in Sergipe, Brazil) and those of negative (ultrapure water) controls. While samples from the Japaratuba River generally produced greater responses than those from the Jacarecica River, positive responses were detected for both the test and reference site samples. All the water samples collected in March 2003 were genotoxic. In July 2003, the positive responses were restricted to water samples collected from Sites 1 B and 2 S in the ST cross. The genotoxicity of the water samples was due to mitotic recombination, and the samples produced similar genotoxic responses in ST and HB flies. The spot frequencies found in the July water samples were considerably lower than those for the March water samples, suggesting a seasonal effect. The only sediment samples that were genotoxic were from Site 1 (March and July) and from the Jacarecica River (March). The genotoxins in these samples produced both somatic mutation (limited to the Site 1 sample in HB flies) and recombination. The results of this study indicate that samples from both the Japaratuba and Jacarecica Rivers were genotoxic, with the most consistently positive responses detected with Site 1 samples, the site closest to the putative pollution source.

Abstract. Hydroxyapatite (HAP) is a bioceramic used in the medical and dental areas as a bone replacement factor due to its chemical similarity to the mineral phase of bones and teeth. Its use in implants stimulate the growth of bone tissue, showing no toxicity or rejection of the host tissue. Its nanostructured form has been shown to be a viable alternative for photoprotection when doped with metal ions, such as trivalent chromium (Cr + ³). Due to the reach of this form among the population, this work evaluated the mutagenic potential of pure nanostructured hydroxyapatite (HAP) and doped with trivalent chromium (Cr + ³) (HCrIII) by means of the Somatic Mutation and Recombination Test (SMART Test) on Drosophila melanogaster Meigen, 1830 (Diptera: Drosophilidae) wings. Larvae resulting from standard crosses (ST) and high metabolic bioactivation (HB), treated with PAH and with HCrIII at concentrations 16.66 mg/mL, 8.33 mg/mL, and 4.16 mg/mL. As positive and negative controls, urethane and dodecyl sulfate sodium (SDS) were used, respectively. The frequencies of the different categories of mutant spots observed in offspring of HAP (HAP) and HCrIII treated crosses were not significantly different from those observed in the negative control. These data show that pure and chromium-doped (Cr + ³) nanoestructured hydroxyapatite do not exhibit mutagenicity. Keywords

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Uma informação, que geralmente impressiona como advertência: “CONTÉM FENILALANINA”, encontra-se em embalagens de alimentos, como alguns refrigerantes, gelatina e suplementos alimentares. Muitas pessoas, desconhecendo seu real significado, questionamse quanto ao “risco” de ingerir esses alimentos. [...]