A mycotoxin Quality Control Material naturally contaminated with Ochratoxin A at a concentration of 4.2ppb. This QCM was prepared in an ISO 9001 production facility and concentration(s) calculated in an ISO 17025 accredited laboratory using HPLC and/or LC-MS/MS methodology. A certificate of analysis is included with every Quality Control Material purchased. All QCMs are thoroughly homogenized to 100% through 30 mesh (0.595mm) to ensure uniform contamination distribution of the analyte to represent the best estimate of the true value as obtained by one laboratory. Quality Control Materials are conveniently packaged as 100g quantities in a resealable foil packet.