RESUMO

The application of excessive fertilizer represents a primary source of entry for perchlorate into crop systems and thus has raised widespread concern regarding food safety. Several studies have reported the occurrence of perchlorate in vegetables. However, limited information is available on the fate of perchlorate in the soil-plant system. In this study, we performed field experiments to evaluate the effects of the application rate of Chilean nitrate fertilizer and the type of fertilization (manual or fertigation) on the uptake of perchlorate by plants grown in open fields. Interestingly, in the control, chard and spinach accumulated 21.3 and 25.9 µg kg-1, respectively. For both agronomic practices, the content of perchlorate in chard and spinach increased as the fertilizer application rate increased, with fertigation promoting more significant accumulations. Spinach accumulated almost two times more perchlorate than chard for all treatments; however, the concentrations generally remained below regulatory values. The intake of spinach and chard presented a low risk to human health for all age groups. These findings enhance our understanding of the environmental impact of the use of fertilizers in agriculture and food safety.

Assuntos

RESUMO

The accumulation of arsenic (As) in vegetables poses a risk of contamination to humans via the food chain. Two chard (var. cicla and var. d'ampuis) crops were grown for 60 days in greenhouses on Aridisol soil, and irrigated with water from Pastos Chicos, Jujuy (Argentina). The soil and water used in the trial presented 49 and 1.44 mg/L As concentration levels, respectively. Total dry biomass (TDB) and total As were determined in soils, roots and leaves. The latter was quantified by atomic absorption spectrometry with hydride generation, and bioconcentration and translocation factors were determined. TDB in var. cicla showed statistically significant differences when the plant was cultivated in control soil and watered with the toxicant (2.04 g), as compared with the treatment without exposure (2.8 g). TDB in var. d'ampuis presented statistically significant differences with respect to that of the control when the plants were grown in soils with As and watered with the toxicant (3.3 g). This variety increased its biomass in the presence of As. In the two Swiss chard varieties evaluated, the largest As accumulation in root and leaves was found when they were cultivated in contaminated soil and watered with distilled water. The presence of the toxicant in the leaves exceeded the limits established by Código Alimentario Argentino, i.e. 0.30 mg/kg. Total target hazard quotient (THQ) values for As were higher than 1, suggesting that consumers would run significant risks when consuming these chard varieties. Furthermore, it was determined that the carcinogenic risk (CR) posed by this type of exposure to As exceeded the acceptable risk level of 1 × 10-6. Based on this evidence, we may conclude that consuming chard cultivated on the evaluated site brings about considerable risks to local residents' health.

Assuntos

RESUMO

Background: reports from traditional medicine suggest that chard (Beta vulgaris L. var Cicla) can have remarkable effects in diabetes therapy. Objective: to evaluate the cytotoxic activity of chard extracts in cell lines and determine the viability of cultured porcine pancreatic islets added with or without chard extracts. Methods: cytotoxic activity of chard extracts was assessed in non-tumor and tumor cell lines using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] technique, and the ability of extracts to maintain porcine pancreatic islets viability and regeneration in vitro was tested. Results: the 50% cytotoxic concentration (CC50) of extracts for non-tumor cell lines was above 1,000 μg/mL, while it was 825 μg/mL, 283 μg/mL, 136 μg/mL and 380 μg/mL, for hexane, ethyl acetate, ethanol and water extracts in the tumor cell line, respectively. The CC50 ratio between cell lines indicates that ethanol extract is 7.5 times more toxic to tumor than non-tumor cell lines. There was an increase in viability of porcine pancreatic islets cultured with aqueous, ethyl acetate, and ethanol extracts compared with standard media (CMRL1066) and Cyclosporine A (CsA) control groups. Furthermore, a greater than one regeneration index of islets cultured with ethanol extract at 1,000 μg/mL and 500 μg/mL concentrations during 15 days was observed, which remained constant and was significantly higher than CsA group. Conclusions: these results suggest that chard metabolites should be researched to develop antitumor therapies and human pancreatic islets recovery in diabetes treatment.

Antecedentes: reportes de medicina tradicional sugieren que la planta acelga (Beta vulgaris L. var Cicla) es importante en el tratamiento de enfermedades como la diabetes. Objetivo: evaluar la citotoxicidad de concentraciones de extractos de acelga en líneas celulares y determinar la viabilidad de islotes pancreáticos porcinos cultivados con y sin extracto de acelga. Método: se evaluó la actividad citotóxica en líneas celulares tumorales y no tumorales, con la técnica del MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]. Específicamente se hicieron ensayos para comprobar si los extractos de acelga tienen la capacidad de mantener la viabilidad de islotes pancreáticos porcinos aislados e influir en su regeneración in vitro. Resultados: la concentración citotóxica al 50% (CC50) de los extractos en líneas no tumorales fue mayor de 1.000 μg/mL, mientras que para los extractos en hexano, acetato de etilo, etanol y agua fue de 825 μg/mL, 283 μg/mL, 136 μg/mL y 380 μg/mL, respectivamente, en líneas tumorales. La proporción CC50 encontrada indica que el extracto en etanol es 7,5 veces más tóxico para las líneas celulares tumorales que para las no tumorales. Igualmente encontramos un aumento en la viabilidad de los islotes pancreáticos porcinos cultivados con extracto acuoso, de acetato en etilo y etanol en comparación con el medio de cultivo estándar (CMRL1066) y un control inhibidor que contenía medio con Ciclosporina A (CsA). Además, se encontró que el índice de regeneración era mayor de uno en los islotes cultivados con el extracto en etanol a concentraciones de 1.000 μg/mL y 500 μg/mL durante 15 días, que se mantuvo constante y fue significativamente mayor en comparación con el grupo de CsA. Conclusión: estos resultados sugieren que los metabolitos de la acelga podrían ser utilizados en la investigación de nuevos fármacos para el desarrollo de terapias antitumorales y recuperación de islotes pancreáticos en el tratamiento de la diabetes.

Antecedentes: relatos encontrados em medicina sugerem que a planta acelga (Beta vulgaris L. var Cicla) tem un papel importante no tratamento das doenças como a diabetes. Objetivo: avaliar a citotoxicidade de concentrações de extratos em linhagens celulares e determinar a viabilidade de ilhotas pancreáticas de porcos cultivadas com e sem extrato de acelga. Métodos: neste trabalho foi avaliada a atividade citotóxica dos extratos da acelga em linhagens celulares tumorais e não tumorais, usando a técnica do MTT [3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide]; além disso, foram feitos ensaios para verificar a capacidade que têm os extratos para manter a viabilidade das ilhotas pancreáticas isoladas de porcos e a influência em sua regeneração in vitro. Resultados: a concentração citotóxica ao 50% (CC50) dos extratos em linhagens não tumorais está acima de 1000 μg/mL, enquanto para os extratos de hexano, acetato de etilo, etanol y água é de 825 μg/mL, 283 μg/mL, 136 μg/mL y 380 μg/mL, respectivamente, em linhagens tumorais. A proporção CC50 entre a célula indica que o extrato de etanol é 7,5 vezes mais tóxico para as linhas celulares tumorais que para as linhas não tumorais. Houve um aumento na viabilidade dos isolados pancreáticos de porcos cultivados com extrato aquoso, de acetato de etilo y etanol, em comparação com o meio de cultura padrão (CMRL 1066) e um controle inibitório contendo meio com Ciclosporina A (CsA). Encontrou-se também uma taxa de regeneração maior do que um em ilhotas cultivadas com concentrações de 1000 μg/mL e 500 μg/mL durante 15 días, que se manteve constante e foi significativamente mais elevada em comparação com a CsA. Conclusões: estes resultados sugerem que os metabolitos da acelga poderiam ser usados para a pesquisa de novas drogas para o desenvolvimento de terapias antitumorais e recuperação de ilhotas pancreáticas para o tratamento da diabetes.