Analysis of Herbicide Residues and Organic Priority Pollutants in Selected Root and Leafy Vegetable Crops in Plateau State, Nigeria

Abstract

Herbicide residues and organic priority pollutants in roots and leafy vegetable crop samples from Plateau State, Nigeria were determined using gas chromatography mass spectrometry (GCMS). The average concentration of the herbicide residues such as atrazine and 2,4-D which were discovered to be more in the root crops and nuts (cassava, yam, potato, groundnuts) are 0.04mg/kg and 0.02mg/kg respectively. The distribution of pendimethalin and paraquat in the root crops was scanty, except for paraquat concentration in potato which was abnormally high (0.67mg/kg). The distribution of herbicide residues in leafy vegetables under investigation was very scanty as it was not detected in most of the samples. The organic priory pollutants identified includes; organochlorines, benzene amine, polyaromatic hydrocarbons (PAHs) phthalate and phenols, they were found to occur in the samples in the rates of 6.98, 16.25, 4.67, 37.12 and 9.28% respectively. Other organic priority pollutants identified which was not any of the organic pollutants family identified above had an occurrence rate of 25.52%. The conclusion and the recommendation arrived at in this work was that when root crops are almost ripe, herbicides should not be applied in those farmland as it was observed that the farming practice in this area is characterized by mix cropping, as such herbicides and other pesticides are applied to control weed and other pests which tends to affects the root crops when the tubers are formed. This makes the residues of such pesticides to be absorbed by the tubers prior to harvest, and the consumption of such could constitute a health risk.