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Fumonisin B1 (FB1) and fumonisin B2 (FB2) are mycotoxins mainly produced by Fusarium verticillioides and Fusarium proliferatum, which are field pathogens of maize. A survey was conducted on the incidences of FB1 and FB2 in both maize and derived products purchased in Portugal. The analytical method involved extraction with methanol-water, clean-up by immunoaffinity column and derivatization with naphthalene-2,3-dicarboxaldehyde. Determination was carried out by high-performance liquid chromatography (HPLC) with spectrofluorimetric detection, with liquid chromatography/mass spectrometry (LC/MS) confirmation. The presence of FB1 and FB2 was determined in 67 samples of maize and maize-based foods, such as flour, semolina, starch, sweet maize, cornflakes and other breakfast cereals, and snacks collected in 2005. FBs were found in 15 samples at concentrations ranging from 113 to 2026 µg kg-1. Two of the samples showed higher contamination levels than the limits established by the European Commission Regulation. None of the samples contained levels of fumonisins that would lead to an exposure exceeding the tolerable daily intake (TDI). [ABSTRACT FROM AUTHOR]

One hundred samples of dried fruits (20 dried raisins, 20 walnuts, 20 peanuts, 20 dried figs and 20 pistachios) and 20 samples of rice purchased from retail shops in the Rabat and Salé area in Morocco were analysed for ochratoxin A (OTA) by immunoaffinity clean-up (IAC) and liquid chromatography (LC) with fluorescence detection. The limit of quantification (LOQ) (S/N = 10:1) of OTA was 0.02 ng g-1 in rice, 0.03 ng g-1 in pistachio, peanut and walnut, and 0.03 ng g-1 in dried raisins and dried figs. The incidences of occurrence of OTA in dried raisins, walnuts, peanuts, dried figs and rice were 30, 35, 25, 65 and 90%, respectively. Analytical results showed that pistachio samples contained no detectable OTA, but concentrations ranged from 0.02 ± 0.01 to 32.4 ± 2.10 ng g-1 in rice, from 0.10 ± 0.05 to 2.36 ± 0.75 in peanut, from 0.03 ± 0.01 to 1.42 ± 0.45 in dried figs, from 0.05 ± 0.02 to 4.95 ± 0.02 in dried raisins, and from 0.04 ± 0.01 to 0.23 ± 0.05 in walnuts. The results also showed that 15% of the total number of rice samples analysed exceeded the 2002 regulatory limit set by European Union regulations for cereals. This is the first report on the occurrence of OTA in dried fruits and rice available in Morocco. [ABSTRACT FROM AUTHOR]

A total of 634 samples of oranges, tangerines, peaches, nectarines, khakis and watermelons were collected from an Agricultural Valencia Community Cooperative during the May 2001 to April 2003 campaigns and they were analysed for 15 pesticides among those recommended for pest treatment. A conventional multiresidue analytical procedure based on ethyl acetate extraction was used followed by gas chromatography coupled to a nitrogen phosphorus detector for routine analysis; and mass spectrometry was performed for confirmation. Recovery studies with spiked samples at 0.5  mg  kg -1 for each pesticide ranged from 52% for acephate to 87% for fenthion with a standard deviation [ABSTRACT FROM AUTHOR]