Contamination levels, occurrence pattern and associated risk of organophosphate pesticide residues in spices and herbs sold in southern Nigeria

This study investigated the contamination levels, occurrence pattern and associated health risks of organophosphate pesticide residues in spices and herbs sold in southern Nigeria. Fifty-two samples of commonly consumed spices and herbs were purchased from multiple locations in southern Nigeria and subjected to extraction using dichloromethane/n-hexane (1:1, v/v). Thereafter, the extracts were analysed for 14 OPPs on gas chromatograph-mass spectrometry. The contamination levels of the$\mathrm{\sum}$14 OPPs in the spices and herbs ranged between 4.96 and 795 ng/g. The average OPP concentrations in the spices and herbs were in the order of diazinone > chlorpyriphos methyl > pyrazophos > isazophos > quinalphos > phosalone > pirimiphos methyl > chlorpyrifos > azinphos ethyl > pirimiphos ethyl > EPN > fenitrothion > pyraclofos > triphenyl phosphate. The OPPs concentrations in the spices and herbs were below the maximum residue limits (MRLs) established by FAO/WHO. The risk estimated using hazard index indicated the absence of non-carcinogenic risk from the intake of these spices and herbs except for seven samples in the case of children intake. Although the findings suggest minimal health risks from OPPs through intake of these spices and herbs, we recommended that there is need for continuous monitoring of spices and herbs sold generally in Nigeria markets for pesticides contamination and the appropriate regulators should establish MRLs for OPPs in foodstuffs in Nigeria and ensure strict compliance with the MRLs of contaminants in food and drugs.