Assays of genotoxic damage in peripheral blood lymphocytes of individuals occupationally exposed to different x-ray systems in hospital radiology departments.

We obtained peripheral blood lymphocyte samples from individuals occupationally exposed to X-rays in hospital radiology departments that use different radiology systems: analog film (AF), computerized radiology (CR), or digital radiology (DR). The micronucleus test (MNT) and comet assay were performed on the samples. Micronucleus cell counts (means vs. controls, i.e., individuals not occupationally exposed to ionizing radiation) were as follows: AF, 1.96 ± 0.21 vs 1.2 ± 0.25; CR, 1.89 ± 0.15 vs 1.31 ± 0.36; and DR, 1.75 ± 0.11 vs 1.59 ± 0.32. For the comet assay, damage scores were as follows; AF, 0.84 ± 0.22 vs 0.47 ± 0.04; CR, 0.64 ± 0.26 vs 0.43 ± 0.04; and DR, 0.56 ± 0.19 vs 0.49 ± 0035. These findings were consistent with cytogenetic damage due to radiation exposure.

In vitro assessment of the genotoxic and cytotoxic effects of boiled juice (tucupi) from Manihot esculenta Crantz roots.

The population of Pará (a state in Brazil) has a very characteristic food culture, as a majority of the carbohydrates consumed are obtained from cassava (Manihot esculenta Crantz) derivatives. Tucupi is the boiled juice of cassava roots that plays a major role in the culinary footprint of Pará. Before boiling, this juice is known as manipueira and contains linamarin, a toxic glycoside that can decompose to hydrogen cyanide. In this study, the cytotoxic and genotoxic effects of tucupi on cultured human lymphocytes were assessed using the comet assay and detection of apoptosis and necrosis by differential fluorescent staining with acridine orange-ethidium bromide. Tucupi concentrations (v/v) were determined using the methylthiazole tetrazolium biochemical test. Concentrations of tucupi that presented no genotoxic effects (2, 4, 8, and 16%) were used in our experiments. The results showed that under our study conditions, tucupi exerted no genotoxic effects; however, cytotoxic effects were observed with cell death mainly induced by necrosis. These effects may be related to the presence of hydrogen cyanide in the juice.