Evaluation of biochemical and redox parameters in rats fed with corn grown in soil amended with urban sewage sludge
Nenhuma Miniatura disponível
Data
2013-09-01
Autores
Grotto, Denise
Carneiro, Maria Fernanda Hornos
Sauer, Elisa
Garcia, Solange Cristina
de Melo, Wanderley José [UNESP]
Barbosa, Fernando
Título da Revista
ISSN da Revista
Título de Volume
Editor
Resumo
The increased production of urban sewage sludge requires alternative methods for final disposal. A very promising choice is the use of sewage sludge as a fertilizer in agriculture, since it is rich in organic matter, macro and micronutrients. However, urban sewage sludge may contain toxic substances that may cause deleterious effects on the biota, water and soil, and consequently on humans. There is a lack of studies evaluating how safe the consumption of food cultivated in soils containing urban sewage sludge is. Thus, the aim of this paper was to evaluate biochemical and redox parameters in rats fed with corn produced in a soil treated with urban sewage sludge for a long term. For these experiments, maize plants were grown in soil amended with sewage sludge (rates of 5, 10 and 20. t/ha) or not (control). Four different diets were prepared with the corn grains produced in the field experiment, and rats were fed with these diets for 1, 2, 4, 8 and 12 weeks. Biochemical parameters (glucose, total cholesterol and fractions, triglycerides, aspartate aminotransferase and alanine aminotransferase) as well the redox state biomarkers such as reduced glutathione (GSH), malondialdehyde (MDA), catalase, glutathione peroxidase and butyrylcholinesterase (BuChE) were assessed. Our results show no differences in the biomarkers over 1 or 2 weeks. However, at 4 weeks BuChE activity was inhibited in rats fed with corn grown in soil amended with sewage sludge (5, 10 and 20. t/ha), while MDA levels increased. Furthermore, prolonged exposure to corn cultivated in the highest amount per hectare of sewage sludge (8 and 12 weeks) was associated with an increase in MDA levels and a decrease in GSH levels, respectively. Our findings add new evidence of the risks of consuming food grown with urban sewage sludge. However, considering that the amount and type of toxic substances present in urban sewage sludge varies considerably among different sampling areas, further studies are needed to evaluate sludge samples collected from different sources and/or undergoing different types of treatment. © 2013 Elsevier Inc.
Descrição
Palavras-chave
Biochemical parameters, Food safety, Oxidative stress, Risk assessment, Urban sewage sludge, alanine aminotransferase, arsenic, aspartate aminotransferase, barium, cadmium, catalase, cholesterol, cholesterol derivative, cholinesterase, chromium, copper, glucose, glutathione, glutathione peroxidase, malonaldehyde, mercury, molybdenum, nickel, selenium, triacylglycerol, zinc, biochemical composition, biomarker, enzyme activity, fertilizer, food safety, maize, redox conditions, risk assessment, rodent, sewage, sludge, soil amendment, animal experiment, animal food, animal model, concentration (parameters), controlled study, enzyme inhibition, evaluation research, field study, food contamination, grain, long term exposure, male, nonhuman, oxidation reduction state, plant growth, rat, soil pollution, toxicity testing, urban area, urban sewage sludge, Rattus, Zea mays
Como citar
Ecotoxicology and Environmental Safety, v. 95, p. 188-194.