Mycotoxin toxicity occurs at very low concentrations, therefore sensitive and reliable methods for their detection are required. Consequently, sampling and analysis of mycotoxins is of critical importance because failure to achieve a suitable verified analysis can lead to unacceptable consignments being accepted or satisfactory shipments unnecessarily rejected. The general mycotoxin analyses carried out in laboratories are still based on physicochemical methods, which are continually improved. Further research in mycotoxin analysis has been established in such techniques as screening methods with TLC, GC, HPLC, and LC-MS. In some areas of mycotoxin method development, immunoaffinity columns and multifunctional columns are good choices as cleanup methods. They are appropriate to displace conventional liquid-liquid partitioning or column chromatography cleanup. On the other hand, the need for rapid yes/no decisions for exported or imported products has led to a number of new screening methods, mainly, rapid and easy-to-use test kits based on immuno-analytical principles. In view of the fact that analytical methods for detecting mycotoxins have become more prevalent, sensitive, and specific, surveillance of foods for mycotoxin contamination has become more commonplace. Reliability of methods and well-defined performance characteristics are essential for method validation. This article covers some of the latest activities and progress in qualitative and quantitative mycotoxin analysis.

Method validation for quantitative analysis of aflatoxins (AFs), ochratoxin A (OTA) and zearalenone (ZEA) in cereals using HPLC with fluorescence detector (FLD) is described. Mycotoxins were extracted with methanol : water (80 : 20) and purified with a multifunctional AOZ immunoaffinity column before HPLC analysis. The validation of the analytical method was performed to establish the following parameters: specificity, selectivity, linearity, limits of detection (LOD) and quantification (LOQ), accuracy, precision (within- and between-day variability), stability, robustness, measurement of performance, and measurement of uncertainty. Calibration curves were linear (r > 0.999) over the concentration range, from the LOQ to 26, 40 and 400 ng/g for AFs, OTA and ZEA, respectively. LOD and LOQ were 0.0125 and 0.05 ng/g for aflatoxin B1 (AFB1) and G1 (AFG1), 0.0037 and 0.015 ng/g for aflatoxin B2 (AFB2) and G2 (AFG2), as well as 0.05 and 0.2 ng/g for OTA and 0.5 and 2 ng/g for ZEA, respectively. The mean recovery values were 77-104% for different concentrations of AFs, OTA and ZEA in spiked cereal samples. Both intra- and inter-day accuracy and precision were within acceptable limits. This method was successfully applied for the simultaneous determination of mycotoxins for 60 cereal samples collected from Malaysian markets. Fifty per cent of the cereal samples were contaminated with at least one of these mycotoxins, at a level greater than the LOD. Only one wheat sample and two rice samples were contaminated with levels greater than the European Union regulatory limits for AFs and OTA (4 and 5 ng/g). The means and ranges of mycotoxins obtained for the cereal samples were 0.4 ng/g and 0.01-5.9 ng/g for total AFs; 0.18 ng/g and 0.03-5.3 ng/g for OTA; and 2.8 ng/g and 2.4-73.1 ng/g for ZEA, respectively. The results indicate that the method is suitable for the simultaneous determination of AFs, OTA and ZEA in cereals and is suitable for routine analysis.

Aflatoxins were surveyed in 256 rice samples taken from retail markets in different provinces of Iran during October 2007 and July 2008. A methanol/water (80 : 20, v/v) mixture and an aflatoxin immunoaffinity column (IAC) were used for extraction and clean-up. Mycotoxins were determined using HPLC with fluorescence detection and post-column derivatization using a photo-ionization cell. Levels of contamination ranged 0.0-5.8 ng g(-1) (mean, 1.4 ng g(-1)) and 0.1-6.3 ng g(-1) (mean, 1.6 ng g(-1)) for AFB1 and total aflatoxins, respectively. AFB1 was detected in almost all samples. Results showed that 55 samples (21.5%) were contaminated with more than 2 µg kg(-1) of AFB1, while seven samples (2.7 %) contained more than 4 µg kg(-1) total aflatoxins. The calculated probable daily intake of AFB1 from rice for Iranians ranged 1.4-5.8 ng AFB1 per kg body weight per day for average consumers and, hence. exceeding the estimated provisional maximum tolerable daily intake.

Food poisoning is one of the most addressed health issues and has raised notable concerns. Histamine is the biogenic amine responsible for scombroid poisoning, which is due to the histidine decarboxylation by bacterial decarboxylases in various types of fish and fish products. The present investigation was conducted to measure the concentration of histamine in canned fish samples of tuna in oil (n = 18), tuna in oil with vegetables (n = 15), tuna in brine (n = 9), kilka in oil (n = 9), sardine in oil (n = 3), and mackerel in oil (n = 6) collected from markets in Tehran, Iran. Histamine concentrations were determined with a high-performance liquid chromatography device equipped with a UV detector. For method validation, the correlation coefficient (R2), recovery percentage, relative standard deviation for repeatability, limit of detection, and limit of quantification were 0.99, 82%, 1.3%, 1.5 mg/kg, and 5 mg/kg, respectively. Histamine was detected in 46.6% of the samples, and 18.3% of samples exceeded the histamine limit stipulated by the U.S. Food and Drug Administration (50 mg/kg). The overall mean histamine concentration was 17.36 ± 15.44 mg/kg, with a range of 0 to 88 mg/kg. A significant difference in histamine concentration was found between canned tuna in oil and canned tuna in brine (P < 0.05). However, no significant difference in histamine concentration was found among samples of canned tuna in brine, canned sardine in oil, canned kilka in oil, and canned mackerel in oil. Because of the high histamine concentrations detected in some brands of Iranian canned tuna, precise control programs, hazard analysis critical control point systems, and good hygiene practices should be implemented. HIGHLIGHTS

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