Evaluation of ochratoxin A exposure degree in two Portuguese cities through wheat and maize bread consumption during the winter 2007

The occurrence of OTA in fresh and packed wheat and in maize bread and the evaluation of the exposure degree through their consumption in two Portuguese populations from Porto and Coimbra, during the winter of 2007, were studied. One hundred and sixty eight bread samples, 61 maize and 107 wheat, were analysed by liquid chromatography–fluorescence detection (LC–FD). The results showed that 84% of samples were contaminated, with a maximum level of 3.85 ng/g (above the EU maximum limit, 3 ng/g). Fresh wheat bread presented higher levels than packed wheat bread. Moreover, the traditional maize bread, in either city, was consistently more contaminated than wheat bread, 0.25 vs 0.19 ng/g, and 0.48 vs 0.34 ng/ g for Porto and Coimbra, respectively. Avintes maize bread showed the highest mean contamination and maximum levels. The higher estimated daily intake of OTA from both types of bread in the population of Coimbra compared to Porto reflects the higher average contamination of bread in the first city.

Influencing factors on bread-derived exposure to ochratoxin A: type, origin and composition

The nearly ubiquitous consumption of cereals all over the world renders them an important position in international nutrition, but concurrently allocates exposure to possible contained contaminants. Mycotoxins are natural food contaminants, difficult to predict, evade, and reduce, so it is important to establish the real contribution of each contaminated food product, with the aim to evaluate mycotoxin exposure. This was the key objective of this survey and analysis for ochratoxin A content on 274 samples of commercialized bread in the Portuguese market, during the winter 2007. Different bread products were analyzed through an HPLC-FD method, including traditional types, novel segments, and different grain based bread products. A wide-ranging low level contamination was observed in all regions and types of bread products analyzed, especially in the Porto and Coimbra regions, and in the maize and whole-grain or fiber-enriched bread. Nevertheless, the exposure through contaminated wheat bread continues to be the most significant, given its high consumption and dominance in relation to the other types of bread.

Determination of ochratoxin A in bread: evaluation of microwave-assisted extraction using an orthogonal composite design coupled with response surface methodology

An analytical method using microwave-assisted extraction (MAE) and liquid chromatography (LC) with fluorescence detection (FD) for the determination of ochratoxin A (OTA) in bread samples is described. A 24 orthogonal composite design coupled with response surface methodology was used to study the influence of MAE parameters (extraction time, temperature, solvent volume, and stirring speed) in order to maximize OTA recovery. The optimized MAE conditions were the following: 25 mL of acetonitrile, 10 min of extraction, at 80 °C, and maximum stirring speed. Validation of the overall methodology was performed by spiking assays at five levels (0.1–3.00 ng/g). The quantification limit was 0.005 ng/g. The established method was then applied to 64 bread samples (wheat, maize, and wheat/maize bread) collected in Oporto region (Northern Portugal). OTAwas detected in 84 % of the samples with a maximum value of 2.87 ng/g below the European maximum limit established for OTA in cereal products of 3 ng/g.

Should the U.S. adapt to the world? The first debate on american exceptionalism and its impact on the founding of the United States

This paper aims at putting into perspective the recent, post 9/11 debate on the United States‘ alleged exceptionalism and its impact on the definition of American foreign policy. It reminds the readers that the United States was born as a result of a similar debate, at a time when a crucial choice for its future was to be made. Indeed, the Founding Fathers discarded the revolutionary idea that America was altogether different from other (European) nations and, as such, could succeed in saving republicanism and concentrate on domestic affairs. As Gordon Wood and Harvey Mansfield have shown, the 1787 version of republicanism stood as a departure from its earlier version, and such a change was necessary to the creation of a full-fledged federation, therefore paving the way to the current powerful Federal Republic. The early failure of the exceptionalist creed did not cause its disappearance, as the contemporary form of exceptionalism demonstrates, but created conditions that made an enduring and powerful influence very difficult.