Modified QuEChERS method for the extraction and quantification of persistent organic compounds in vegetables from Mozambican local markets

This study focused on modification of a well-established QuEChERS method by replacing PSA adsorbent with moringa's seed protein (Mor-p) and on the assessment of the consumer health risk of vegetable from Mozambican open markets. Recovery tests were carried out using the acetonitrile: methanol (90:10) combination as the extraction solvent. The recoveries obtained in method validation on GC-MS analytical technique for the target compounds ranged from 104-107% for β-HCH, 74-110% for ϒ-HCH, 69-90% for cypermethrin, 84-94% for p,p’-DDD, 86-108% for p,p’-DDT, 81-114% for 4-nonylphenol and 80-94% for profenophos. In sample analysis of vegetables from the Mozambican open markets were obtained 1.6±0.17 mg.kg−1 for β-HCH, 0.64±0.16 mg.kg−1 for ϒ-HCH, 0.72±0.01 mg.kg−1 for cypermethrin, 0.32±0.02 to 2.0±0.01 mg.kg−1 for p,p’-DDD, 0.36±0.01 to 0.73±0.01 mg.kg−1 for p,p’-DDT, 0.19±0.01 mg.kg−1 for 4-nonylpenol and 2.1±0.34 to 6.2±0.69 mg.kg−1 for profenophos. Overall, the findings indicate potential application of the Mor-p as an alternative adsorbent for the extraction and quantification of persistent organic compounds from raw food items. The results indicated that there is a health risk issues related to the consumption of kale and cabbage sold in Mozambican open markets.