DETERMINATION OF EPOXICONAZOLE RESIDUE LEVEL IN WHEAT AND EFFECTS OF STORAGE, WASHING AND COOKING ON IT

Abstract

Wheat cultivation accounts for 18.23% and 19.80% in terms of area coverage and production respectively as compared to the total cultivated area and production of cereals in Ethiopia. The world pre-harvest losses of crops are caused by insects (15%), pathogens (13%) and weeds (14%). Fusarium head blight (FHB) and other fungal diseases are the major threat to global wheat production and in Ethiopia as well. Epoxiconazole in combination with thiophanate methyl (trade name Rex®Duo) provides high protection against FHB and other fungal diseases are extensively used by wheat producing Ethiopian farmers. The aim of this experimental research is to investigate the epoxiconazole residue level and effect of local food processing on its level in wheat samples collected from local farms in East Arsi zone, Oromia regional state, Ethiopia, at two different harvesting seasons. The harvest of one season was analyzed for epoxiconazole residue level after storage of 1 year. The other (newly harvest) was analyzed just after five months of harvest. The sample preparation was conducted according to 2007.01_QuEChERS extraction method. Washing was performed as per expected local cereal washing method. The cooking was made to bread in oven. The analysis was carried out using liquid chromatography tandem double mass spectrometry. The finding of the study revealed that the epoxiconazole residue level in newly harvest and 1 year stored wheat samples were 0.0035mg/kg and 0.00753mg/kg respectively. On the other hand, investigation of the effect of washing and cooking on epoxiconazole residue level revealed that washing reduces the epoxiconazole residue level by 55.5% while cooking reduces only by 21.8%