Occurrence of microorganisms, aflatoxin, ochratoxin, and heavy metals in paddy and rice produced in Iraq

Abstract

To determine the effect of houseware cleanliness and mill procedure on the contamination level of paddy and its produced rice, paddy and rice samples of seven different mills in three provinces of Iraq were investigated for microorganisms, mycotoxins, and heavy metals. Paddy and rice samples of each mill were gathered during the mills’ operation to determine the effect of mill processing on the contamination level. The result showed that all paddy and rice samples were within the acceptable limit regarding total plate count (TPC) with range 4.8×10³ to 5.6×10⁵ cfu/g of paddy and 6.0×10² to 2.1×10⁵ cfu/g for rice. Some paddy samples exceeded the FDA limit of molds and yeast such as mills in Babel and Alnajaf provinces with 1.7×10⁴ and 3.5×10⁴ cfu/g respectively. Paddy samples of the same mentioned mills had total coliform count more than the FDA limit (1.0×10⁴ cfu/g), while all rice samples had less than the FDA limit, however, some rice samples exceeded Iraqi limit (1.0×10³ cfu/g). E. coli bacteria has been detected in paddy samples of the same two mills, and the count was within the FDA limit. For rice samples, E. coli was less than 3 cell/g, which was the detection limit of the conducted method. Some paddy and rice samples overpassed the authorized limit (CEC and IQS) of total aflatoxin (AFTs) with range between 1.4 to 10.2 μg/kg for paddy samples and 1.1 to 8.8 μg/kg for rice samples. Most samples overpassed ochratoxin A (OTA) limit (CEC), which was 5 μg/kg for paddy and 3 μg/kg for rice. Cadmium concentration was within the limit approved by CAC and IQS, while most samples overpassed lead (Pb) concentration. In conclusion, the mill processing reduced microorganisms count, while it had no clear effect on the mycotoxin reduction and heavy metals concentration. Enhancing the safety of the produced rice in Iraq should be considered in the next planning.