Ozonation of agri-food products for reducing mycotoxin contamination: challenges in grains and particulates processing.

This study evaluated differences in the efficiency of ozonation process to reduce the natural contamination of two mycotoxins, deoxynivalenol (DON) and zearalenone (ZEN), in wheat grains and particulate products. Three different products were used, each one representing a different structure and mycotoxin distribution: (1) wheat grains, with natural mycotoxin distribution inside and among the grains; (2) homemade pellets, with homogenous mycotoxin distribution; (3) ground homemade pellets, with homogeneous mycotoxin distribution, and smaller particles. The ozonation of naturally contaminated wheat grains did not reduce the concentrations of DON and ZEN. When the variability of contamination among replicates was reduced by the production of homemade pellets showed, the ozonation provides a reduction of 14% of ZEN concentration. Reducing the size of particles by grinding the homemade pellets, a reduction of DON (11%) and ZEN (31%) was observed, which was evidenced by the higher ozone consumption during the process. Therefore, some limitations of ozonation of grains and particulate products, such as particle dimensions and distribution of natural contamination of mycotoxins affect the degradation of DON and ZEN under real conditions. Because of this, further studies to evaluate the effectiveness of ozonation should also be performed in samples naturally contaminated to produce robustness results.

Five thousand years of bellyaches: Exploring boron concentration in ancient populations of the Atacama Desert.

OBJECTIVES: This study explores whether ancient Atacama Desert populations in northern Chile were exposed to endemic boron contamination. MATERIALS AND METHODS: Using Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS), we studied 144 strands of ancient mummy hair, ranging from 3000 B.C. to 1500 A.D., excavated from the Lluta, Azapa, and Camarones valleys in northern Chile. We tested whether these ancient populations showed signs of significant boron concentration in hair tissue. RESULTS: On average, all individuals from these valleys showed high boron concentrations, ranging from 1.5 to 4 times above the average boron concentration in contemporary hair (baseline <0.85 µg/g). The boron concentration in mummy hair varied according to the main geographic areas mentioned above. CONCLUSIONS: The rivers of northern Chile have high geogenic boron concentrations. They contain 38 times above the recommended limit for human consumption. Geogenic boron contamination likely played a role in population morbidity and the types of crops that were cultivated in antiquity. The ancient populations were chronically affected by boron overexposure, suggesting that ancient geogenic water contamination should be considered when discussing the biocultural trajectories of ancient populations.

Living in poisoning environments: Invisible risks and human adaptation.

This article describes the hidden natural chemical contaminants present in a unique desert environment and their health consequences on ancient populations. Currently, millions of people are affected worldwide by toxic elements such as arsenic. Using data gathered from Atacama Desert mummies, we discuss long-term exposure and biocultural adaptation to toxic elements. The rivers that bring life to the Atacama Desert are paradoxically laden with arsenic and other minerals that are invisible and tasteless. High intake of these toxic elements results in severe health and behavioral problems, and even death. We demonstrate that Inca colonies, from Camarones 9 site, were significantly affected by chemical contaminants in their food and water. It appears however, some modern-day Andean populations resist the elevated levels of arsenic exposure as a result of positive selection mediated via the arsenic methyltransferase enzyme and display more tolerance to high chemical doses. This article further debate the effects of natural pollution and biocultural adaptation of past populations.

Natural occurrence of hexavalent chromium in a sedimentary aquifer in Urânia, State of São Paulo, Brazil

Anomalous concentrations of hexavalent chromium have been detected in ground-water of the Adamantina Aquifer inat least 54 municipalities located in the northwestern region of the State of São Paulo, southeast Brazil, occasionallyexceeding the permitted limit for human consumption (0.05 mg.L-1). An investigation was conducted in the municipality of Urânia, where the highest concentrations of chromium were detected regionally. It was defined that the originof this contamination is natural, since high concentrations of chromium were detected in aquifer sandstones (averageof 221 ppm) and also in pyroxenes (6000 ppm), one of the main heavy minerals found in the sediments. Besides, noother possible diffuse or point sources of contamination were observed in the study area. Stratification of ground-waterquality was observed and the highest concentrations of Cr6+ were detected at the base of the aquifer (0.12 mg.L-1),where ground-water shows elevated values for redox potential (472.5 mV) and pH (8.61). The origin of Cr6+ in water may be associated with the weathering of pyroxene (augite), followed by the oxidation of Cr3+ by manganese oxides. The highest concentrations of Cr6+ are probably related to desorption reactions, due to the anomalous alkaline pHfound in ground-water at the base of the aquifer.

Concentrações anômalas de cromo hexavalente foram detectadas em águas subterrâneas do Aqüífero Adamantina em pelo menos 54 municipalidades localizadas na região noroeste do Estado de São Paulo, sudeste do Brasil, algumas vezes ultrapassando o limite máximo permitido para consumo humano (0,05 mg.L-1). Um estudo foi realizado no município de Urânia, onde as mais elevadas concentrações de cromo da região foram detectadas. A origem da contaminação foi definida como natural, pois foram detectadas concentrações de cromonos arenitos do aqüífero (média 221 ppm) e em piroxênios (6000 ppm), um dos principais minerais pesados encontrados nos sedimentos. Além disso, não foram observadas outras possíveis fontes de contaminação difusas ou pontuais naárea de estudo. Uma estratificação da qualidade da água no aqüífero foi observada e as mais elevadas concentrações de Cr6+ foram detectadas na base do aqüífero (0,12 mg.L-1), onde as águas subterrâneas apresentam valores elevados de potencial redox (Eh = 472,5 mV) e de pH (8,61). A origem do Cr6+ na água deve estar associada com o intemperismo do piroxênio (augita), seguida da oxidação do Cr3+ pelos óxidos de manganês. As maiores concentrações de Cr6+ estão provavelmente ligadas com reações de desorção, devido ao pH anomalamentealcalino da água subterrânea na base do aqüífero.

Determinación de fluoruro en aguas de Rinconadillas (Provincia de Jujuy) / Determination of the presence of fluorides in groundwaters to Rinconadillas (Jujuy)

El objetivo de la investigación fue determinar la presencia de fluoruros de aguas procedentes de vertientes y pozos cavados en la localidad de Rinconadillas de la Puna Jujeña. Dicha región fue seleccionada debido a que se quería corroborar la presencia de fluoruros, encontrados en la década del ‘80 por el organismo Agua Potable de la provincia de Jujuy, como así también ver si existía variación en la concentración de este contaminante natural en el transcurso del tiempo. La evaluación se realizó sobre 11 muestras de agua de vertientes y de pozos, que representan la totalidad de las fuentes en toda la localidad de Rinconadillas y alrededores. Otras 9 muestras fueron tomadas de Purmamarca, Tumbaya, Volcán, San Salvador de Jujuy y Palpalá, localidades que se alejan de Rinconadillas. Estas muestras consideradas testigos fueron seleccionadas sabiendo que, en estudios realizados anteriormente, no contenían fluoruros. De la totalidad de las muestras recolectadas en Rinconadillas, el 82 % superó el límite máximo recomendado por el Código Alimentario Argentino mientras que menos del 10% se encontraron por debajo de lo reglamentado. Las concentraciones de esta zona fueron superiores a las registradas en las muestras tomadas como referencias, determinándose diferencias significativas entre ambos grupos (p = 0,001). De las muestras testigos sólo una superó el límite superior recomendado por el Código Alimentario Argentino. Algunas de las concentraciones determinadas en el presente estudio fueron mayores a los registros de 15 años atrás y podrían indicar una variación creciente en el tiempo. Se ha observado que la población se ha dispersado en las cercanías a Rinconadillas con nuevas fuentes de aguas de bebida, que sólo reciben una eventual cloración. Se ha observado también en la población del lugar una marcada fluorosis dentalque debería ser evaluada clínica y epidemiológicamente.

The aim of this study was to determine the presence of fluorides in groundwaters from springs and wells belonging to Rinconadillas, a small town located in “La Puna” in the Province of Jujuy. This region was selected because fluoride has been detected during the '80 by Jujuy Water Agency and a comparative study of fluoride levels would provide information about the variation of concentrations of this “natural” contaminant along the time. In “La Puna” the study was conducted on eleven samples of groundwaters from springs and wells from Rinconadilllas and its surroundings. Nine further samples were obtained in Purmamarca, Tumbaya, Volcán, San Salvador de Jujuy and Palpalá, all ofthem far from Rinconadillas. Those samples were selected as prior studies determined that water from such towns does not contain fluoride. Eighty two percent of all the samples collected in Rinconadillas exceeded fluoride limits stated by Argentine Legislation (AL), while less than ten percent of the samples are below the stated values. Fluoride levels from this area were higher than the levels for the reference samples. For the blank samples, only one exceeds the maximum allowed level. Fluoride levels found in this study were higher than those coming from samples that have been analyzed 15 years ago indicating that fluoride levels in waters are increasing. It has also been observed that the population has moved to Rinconadillas surroundings having a drinking water form newsource that is only eventually chlorinated. A remarkable dental fluorosis is observed in the population, which should be clinically and epidemiologically assessed.

Thermolysed and active yeast to reduce the toxicity of aflatoxin

Aflatoxins are hepatotoxic metabolites produced by Aspergillus flavus and A. parasiticus on a number of agricultural commodities. This research was carried out to evaluate the ability of thermolysed and active Saccharomyces cerevisiae to attenuate liver damage caused by aflatoxin. Diets were prepared containing 0 aflatoxin; 400 mug kg-1 aflatoxin; 400 mug kg-1 aflatoxin plus 1% of dehydrated active yeast, and 400 mug kg-1 aflatoxin plus 1% of thermolysed yeast. A bioassay with Wistar rats was conducted for 28 days, and body organs were weighted and analyses of the liver tissue of the animals were performed. The relative weight of heart, kidneys and liver from animals submitted to the different treatments did not show any difference, and liver tissue of animals feeding on the aflatoxin-free diet was adopted as a toxicity-free pattern. Hepatic tissue of animals feeding on diets containing 400 mug kg-1 aflatoxin or the diet supplemented with 1% thermolysed yeast showed clear signs of toxicity and damage. Hepatic tissue of animals feeding on the diet containing 1% of dehydrated active yeast showed less toxicity signs and damage than those receiving the diet containing 400 mug kg-1 aflatoxin. Active, dehydrated yeast had the ability to reduce toxic effects caused by aflatoxin, but thermolysed yeast was not able to alleviate the effects of aflatoxin toxicity.

As aflatoxinas são metabólitos hepatotóxicos produzidos por algumas linhagens de Aspergillus flavus, A. parasiticus e, eventualmente, por A. nomius sobre grande número de produtos agrícolas. Esta pesquisa foi conduzida para avaliar a capacidade de Saccharomyces cerevisiae, nas formas termolisada e desidratada viva, em reduzir os danos causados por aflatoxinas. Para tal, foi preparada uma dieta básica e desta se obtiveram quatro formulações: uma como controle; as demais contaminadas com aflatoxinas na concentração de 400 mig kg-1, sendo duas com posterior adição de 1% de leveduras, uma na forma termolisada e outra como desidratada viva. Um bioensaio com duração de 28 dias foi efetuado com ratos Wistar. Foram realizados os estudos do peso relativo de órgãos internos e a análise do tecido hepático dos animais. Os pesos relativos de órgãos internos de animais submetidos aos diferentes tratamentos não diferiram estatísticamente entre si; o tecido do fígado dos animais submetidos à dieta livre de aflatoxinas foi adotado como padrão de isento de toxidez; o tecido hepático dos animais que receberam dieta controle com aflatoxinas apresentaram sinais claros de toxicidade; os animais que receberam dieta com aflatoxinas + 1% de levedura termolisada apresentaram sinais de toxicidade semelhantes ao controle com aflatoxinas; o tecido hepático dos animais que receberam dieta com aflatoxinas + 1% de levedura viva apresentaram sinais de toxicidade menores do que os animais que receberam a dieta controle com aflatoxinas. As leveduras termolisadas não foram capazes de suprimir os efeitos das aflatoxinas; as leveduras vivas apresentaram habilidade de reduzir os efeitos promovidos por aflatoxinas.

Thermolysed and active yeast to reduce the toxicity of aflatoxin

Aflatoxins are hepatotoxic metabolites produced by Aspergillus flavus and A. parasiticus on a number of agricultural commodities. This research was carried out to evaluate the ability of thermolysed and active Saccharomyces cerevisiae to attenuate liver damage caused by aflatoxin. Diets were prepared containing 0 aflatoxin; 400 mug kg-1 aflatoxin; 400 mug kg-1 aflatoxin plus 1% of dehydrated active yeast, and 400 mug kg-1 aflatoxin plus 1% of thermolysed yeast. A bioassay with Wistar rats was conducted for 28 days, and body organs were weighted and analyses of the liver tissue of the animals were performed. The relative weight of heart, kidneys and liver from animals submitted to the different treatments did not show any difference, and liver tissue of animals feeding on the aflatoxin-free diet was adopted as a toxicity-free pattern. Hepatic tissue of animals feeding on diets containing 400 mug kg-1 aflatoxin or the diet supplemented with 1% thermolysed yeast showed clear signs of toxicity and damage. Hepatic tissue of animals feeding on the diet containing 1% of dehydrated active yeast showed less toxicity signs and damage than those receiving the diet containing 400 mug kg-1 aflatoxin. Active, dehydrated yeast had the ability to reduce toxic effects caused by aflatoxin, but thermolysed yeast was not able to alleviate the effects of aflatoxin toxicity.

As aflatoxinas são metabólitos hepatotóxicos produzidos por algumas linhagens de Aspergillus flavus, A. parasiticus e, eventualmente, por A. nomius sobre grande número de produtos agrícolas. Esta pesquisa foi conduzida para avaliar a capacidade de Saccharomyces cerevisiae, nas formas termolisada e desidratada viva, em reduzir os danos causados por aflatoxinas. Para tal, foi preparada uma dieta básica e desta se obtiveram quatro formulações: uma como controle; as demais contaminadas com aflatoxinas na concentração de 400 mig kg-1, sendo duas com posterior adição de 1% de leveduras, uma na forma termolisada e outra como desidratada viva. Um bioensaio com duração de 28 dias foi efetuado com ratos Wistar. Foram realizados os estudos do peso relativo de órgãos internos e a análise do tecido hepático dos animais. Os pesos relativos de órgãos internos de animais submetidos aos diferentes tratamentos não diferiram estatísticamente entre si; o tecido do fígado dos animais submetidos à dieta livre de aflatoxinas foi adotado como padrão de isento de toxidez; o tecido hepático dos animais que receberam dieta controle com aflatoxinas apresentaram sinais claros de toxicidade; os animais que receberam dieta com aflatoxinas + 1% de levedura termolisada apresentaram sinais de toxicidade semelhantes ao controle com aflatoxinas; o tecido hepático dos animais que receberam dieta com aflatoxinas + 1% de levedura viva apresentaram sinais de toxicidade menores do que os animais que receberam a dieta controle com aflatoxinas. As leveduras termolisadas não foram capazes de suprimir os efeitos das aflatoxinas; as leveduras vivas apresentaram habilidade de reduzir os efeitos promovidos por aflatoxinas.