Ecotoxicological and genotoxic assessment of hospital laundry wastewaters.

The aim of the present study was to assess the ecotoxicity and genotoxicity of hospital laundry wastewaters generated from a regional hospital located in Rio Pardo Valley in the state of Rio Grande do Sul, Brazil. Physicochemical, microbiological, ecotoxicological, and genotoxic analyses were performed, and the results indicate that some parameters were not in accordance with the limit concentrations established by Brazilian and international guidelines for urban wastewaters. Daphnia magna (EC50 2.01%) and Danio rerio (LC50 29.25%) acute toxicity was detected, and sublethal effects were identified in Lactuca sativa (IC25 12.50%) and Allium cepa (IC25 51.25%). Cytotoxicity was observed at the five wastewater concentrations used yielding statistically significant differences (p < 0.05) in the meristematic cells of A. cepa compared with the negative control. The results obtained here warn about the necessity to develop treatment methods that can mitigate the environmental impacts caused by the ecotoxicity and genotoxicity of hospital laundry wastewaters.

Micobiota e micotoxinas em amostras de arroz coletadas durante o sistema estacionário de secagem e armazenamento / Mycobiota and mycotoxins in rice samples collected during the stationary drying and storage system

Considerando as perdas qualitativas e quantitativas no período pós-colheita de grãos, neste trabalho foram avaliadas a contaminação fúngica e as micotoxinas em arroz com casca, durante o sistema estacionário de secagem e armazenamento. As amostras foram coletadas em intervalos de 60 dias durante o armazenamento, em duas alturas do silo-secador. A amostra inicial apresentou 5,4x10(4)UFC g-1, sendo que a contagem aumentou significativamente durante a secagem e o armazenamento, chegando a 10(5)UFC g-1. A contaminação fúngica diferiu no interior do silo-secador, com maior contaminação na porção superior do silo. Os gêneros predominantes foram Aspergillus e Penicillium, com maior ocorrência de A. flavus (26,3 por cento) e P. commune (19,1 por cento). Quatro isolados de A. flavus produziram aflatoxina B1, mas não foram detectadas micotoxinas nas amostras.

Considering the qualitative and quantitative losses in post-harvest of grain, in this research was evaluated fungi and mycotoxins contamination in whole rice (Oryza sativa L.) during the stationary drying and storage system. Samples were collected in a period of sixty days in two heights of the warehouse during storage. The initial sample presented 5.4x10(4)CFU g-1; the contamination increased significantly during drying and storage, up to 10(5)CFU g-1. Fungi contamination was different inside the warehouse with higher contamination in the upper portion. The more abundant fungi genera were Aspergillus and Penicillium, A. flavus (26.3 percent) and P. commune (19.1 percent) which presented higher incidence. Aflatoxin B1 was produced by four A. flavus isolates, but mycotoxins were not detected in the samples.