Pesticide Residue Analysis and Health Risk Assessment in Vegetables from Conventional Farms in Cameron Highlands, Malaysia

Abstract

The current study determines 15 pesticide residues of organochlorine (OCPs), organophosphorus pesticides (OPPs) and pyrethroids (PYRs) in vegetables from agricultural farms in Cameron Highlands, Malaysia, and evaluates the associated health risks. More than 200 vegetable samples were analysed during the wet season (October–January) and dry season (April–July). A multi-residue method was developed for the analysis of pesticides followed by gas chromatography (GC) in combination with an electron-capture detector (ECD). The average recovery was between 60% and 128%, while the relative standard deviation, RSD, was in the range of 0.2%–19.8%. The method validation was conducted by the external standard calibration. The highest concentrations were found in the wet season (5 μg/kg–100 μg/kg), possibly due to air circulation and greater pesticide usage by farmers. Overall, the concentrations ranged from 0.03 μg/kg to 100 μg/kg. Cabbage showed the highest concentration of each pesticide and thus was found to be the most contaminated vegetable amongst other vegetables of the region. The highest combined risk in brassica vegetables for children suggests that children might experience serious adverse health effects. Multivariate analysis shows that farmers are using a mixture of pesticides on vegetables and signifies the importance of pesticides application on crop type.