Metais pesados em alface: aspectos gerais e levantamento das possíveis fontes de contaminação em alface comercializada em feira livre no município de Itumbiara-GO

Abstract

Lettuce is among the most consumed vegetables in Brazil and it is therefore of great importance to investigate its quality with respect to inorganic contaminants, such as heavy metals. These, in turn, can contact the food and contaminate it in different ways, for example through the application of inputs and agricultural correctives, contaminated irrigation water and hair. Potentially toxic metals, which tend to accumulate and are not relevant to living organisms, are cadmium and lead. According to Resolution 42 of ANVISA, the maximum limit of contaminants in vegetables as 0.20 mg kg-1 and 0.30 mg kg-1 for Cd and Pb, respectively. The objective of this work was to conduct a survey about the sources of contamination by heavy metals in lettuce marketed in the free fair municipal of Itumbiara, state of Goiás. This survey is given through a questionnaire applied to the fair. Also, the objective of this study was to investigate the presence of these metals, lead and cadmium, in a sample collected in one of the twelve booths that commercialize one. The methodology used for the evaluation of EPA 3051 in microwaves and an analytical technique used for the detection of these metals for atomic absorption spectrometry. The results of the collected sample show the absence of lead and the presence of cadmium within the standard. The answers obtained by the questionnaire also confirmed that the risk of contamination by heavy metals in vegetables is low.