Safety of foods sold in street fairs: analysis of pesticide residues in lettuce (Lactuca sativa L.)

Pesticides are chemical contaminants that can be found in food. Those with the greatest residual representation include insecticides, fungicides, and herbicides. The objective of this study was to analyze the presence of pesticide residues in lettuce (Lactuca sativa L.) sold at street fairs. This was a quantitative, cross-sectional study, carried out in street fairs in Chapeco, state of Santa Catarina, with producers of fresh vegetables, and consumers, and also analyzed pesticide residues in lettuce from conventional and organic cultivation. Data were collected using a semistructured questionnaire, administered to all producers, and a sample of consumers. Pesticide residues were analyzed in lettuce as it is the most purchased food by consumers. Pesticides surveyed included azoxystrobin, deltamethrin, imidacloprid, and glyphosate, as they are the most frequently applied on farms, and in cultivation of vegetables. Of the 67 vendors active in the seven street fairs, 30 were vegetable and fruit producers, and of these, 17 were conventional producers and 13 were organic farmers. The analysis of pesticide residues in lettuce from conventional production showed residues of azoxystrobin and imidacloprid, but below the maximum residue limits allowed by Anvisa. In samples of organic lettuce, residues of the analyzed pesticides were not detected. From the analysis of residues in lettuce, it is inferred that the food is safe in terms of the pesticides analyzed and that municipal public policies should prioritize systematic monitoring to ensure food safety and encourage the production of organic food.