Determination of benzo(a)pyrene by GC/MS/MS in retail olive oil samples available in Qatar.

A survey was carried out for the presence of benzo(a)pyrene (B(a)P) in olive oils following reports that some batches of Spanish olive-pomace oil and its products contained high levels of B(a)P. Three types of olive oils (1) virgin olive oil, (2) refined olive oil and (3) olive-pomace oil, originating from France, Greece, Italy, the Lebanon, Spain, Tunisia and Turkey, and available on Qatar market, were analysed for B(a)P. Determination was carried out by extraction from a cyclohexane solution with N,N-dimethylformamide: water (9:1), back extraction with cyclohexane, followed by clean-up on a silica gel column and quantification by GC/MS/MS. The recovery and limit of quantitation of B(a)P in olive oils by this method were estimated as 88% and 0.5 microg kg(-1), respectively. B(a)P was detected in amounts below the permitted level of 2 microg kg(-1) in all 31 virgin olive oil samples and in 13 refined olive oil samples. However, all seven samples of Spanish olive-pomace oil produced and packed in Spain and three samples of olive-pomace oil produced in Spain, but packed in Saudi Arabia, were found to be contaminated with B(a)P, the level ranging from 3.1 to 70.8 microg kg(-1). In two samples of olive-pomace oil originating from Greece, B(a)P was not detected.

Occurrence of aflatoxin in commodities imported into Qatar, 1997-2000.

The occurrence of aflatoxin in commodities imported into Qatar was investigated from 1999 to 2000. During the 4 years, 351 samples of susceptible commodities were analysed. Aflatoxin was detected in 71 (20%) samples in the range 0.1-20 microg kg(-1) and in 50 (14%) samples above the permitted level of 20 microg kg(-1). The highest incidence and levels of aflatoxin contamination were recorded in pistachio without shell followed by pistachio with shell. Aflatoxin levels >20 microg kg(-1) in the pistachio samples varied from 8.7 to 33%. The highest level of total aflatoxin found in pistachio without shell was 289 microg kg(-1). A few samples of corn and corn products (three of 54 analysed), peanut and peanut products (nine of 42 analysed) and other nuts like almond, walnut and cashew (one of 40 analysed) were found contaminated with low levels (0.1-20 microg kg(-1)) of aflatoxins. Only one sample of custard powder and one sample of roasted peanut were found with aflatoxin >20 microg kg(-1)