Survey and risk assessment of trace elements in foods from Taiwan containing red mould rice (Monascus) by ICP-MS.

The concentrations of seven trace elements (As, Cd, Cr, Pb, Se, Cu and Zn) in 93 red mould rice (Monascus) food samples in Taipei, Taiwan, were determined by inductively coupled plasma-mass spectrometry (ICP-MS) after wet digestion. The results, calculated in mg kg(-1) (wet weight) for each sample, revealed the general scenario of food safety in Taiwan: As (0.005-12.04), Cd (<0.0005-2.22), Cr (0.014-6.95), Cu (0.012-8.70), Pb (0.001-0.64), Se (<0.001-1.29) and Zn (0.020-67.02). Three food samples were identified with As concentrations higher than regulatory limits: a dietary supplement sample and a seaweed sample with As concentrations that exceeded the limit of Taiwan's health food standard of 2 mg kg(-1), and a canned eel sample with an As concentration that exceeded the limit of Canada's fish standard of 3.5 mg kg(-1). This study suggests that the estimated intakes of these seven trace elements from the consumption of foods containing Monascus pose little risk, as the trace element contents in the majority of samples were lower than the permissible/tolerable intakes per week according to the guidelines recommended by the Food and Agricultural Organization/World Health Organization (FAO/WHO). Moreover, their concentrations in foods containing Monascus differ widely for different food varieties, suggesting that external contaminants and raw materials are the main sources of trace elements. This study shows that ICP-MS is a simple method proposed for the determination of As, Cd, Cr, Pb, Se, Cu, and Zn in foods containing Monascus.

Survey of total mercury in foods from Taiwan containing red mould rice (Monascus) using a direct mercury analyser (DMA).

Total mercury concentrations in 69 red mould rice (Monascus) food samples purchased in Taipei, Taiwan, were determined using the direct mercury analyser (DMA) method. The highest mean levels of total mercury in these samples were observed in samples of canned roast eel (20 µg kg(-1)), soy fibrous product (14 µg kg(-1)), red mould rice (8.5 µg kg(-1)), cereal (7.6 µg kg(-1)), dried pork fibre (7.5 µg kg(-1)), and dietary supplement (7.2 µg kg(-1)). All samples analysed had mercury levels below the limit of 50 µg kg(-1) for food standards in rice, edible oil, and fat of Taiwan. The mercury concentration in the Monascus foods differed widely between different food varieties, suggesting that external contamination and raw materials are the main sources of mercury. This study shows that DMA is a simple method proposed for the determination of total mercury in foods containing Monascus. The method requires no sample pre-treatment, and it minimizes potential sources of contamination. The data (42±2 µg kg(-1)) obtained from five analyses of a standard reference material (apple leaves, NIST-1515) showed good agreement with the certified reference value (44±4 µg kg(-1)) provided by the US National Institute of Standards and Technology (NIST). The precision based on the analysis of standard reference material was 4.1%; the average recovery was 95%.