Pesticide Residues On Local Food Crops: Realities And Recommendations

A recent market basket survey of organophosphate insecticides in Trinidad clearly indicated improper use of this class of insecticides on produce offered for sale to local consumers. In several cases, crops appeared to have been harvested without regard for recommended pre-harvest intervals, as well as being treated shortly before harvest. On many samples, recommended maximum residue levels were exceeded, particularly on celery, on which mixtures of insecticides were frequently and consistently detected. Supervised field trials of five of the most commonly detected organophosphates showed that recommended pre-harvest intervals of each pesticide were often not in accordance with actual field degradation rates. In some cases, residue levels of pesticides declined faster than expected, raising the possibility of re-infestation of crops by pests within the recommended pre-harvest intervals. Our results indicate a pressing need for supervised efficacy and pesticide residue trials, of all pesticides used on food crops under local growing and storage conditions, and offered for sale locally or exported. The recent acceptance of HACCP for food production systems also mandates regular monitoring of edible crops for contaminants, including pesticide residues, to ensure the safety of consumers.