Ochratoxin A levels in foodstuffs marketed in Hong Kong

Ochratoxin A (OTA) is a toxic and potentially carcinogenic fungal toxin found in a variety of food commodities. This study aims to assess the levels of OTA in foods in Hong Kong. About 300 food samples were taken from the local retail market for OTA analysis. Majority of food samples, including local staple food of steamed rice, noodles and congee, were not found to contain measurable amounts of OTA. A sensitive method using immunoaffinity column (IAC) cleanup and HPLC–MS/MS detection was developed to analyze the OTA in these samples. Ochratoxin B (OTB) was used as internal standard. Method validation was performed according to the Commission Decision 2002/657/EC. The OTA levels in the more commonly consumed food items were generally below the maximum limits established by EC legislation. The presence of measurable amount of OTA was reported in 101 food items (32% of all samples), with levels ranging from 0.01 to 2.09 μg/kg (ppb), all of which were well below the legal limits for the respective commodities in the European Union. The low OTA results also suggested that food commodities available in the retail market in Hong Kong are unlikely to pose an adverse health risk to the consumers with respect to OTA toxicity.