RESÍDUOS DE 14C-PROCHLORAZ EM MANGAS IRRADIADAS

O objetivo deste trabalho foi avaliar os niveis residuais de Prochloraz aplicado em mangas, na pre e pos-colheita apos o tratamento com radiacao. Os frutos foram submetidos a radiacao gama na dose de 1,0 kGy visando verificar se a mesma induziu a degradacao do fungicida. As mangas tratadas na pos-colheita foram armazenadas por 21 dias a 12 °C. Os residuos de Prochloraz nao apresentaram decrescimo durante o periodo de carencia (21 dias) estabelecido pela Legislacao Brasileira de Agrotoxicos. O armazenamento refrigerado (12 °C) e a irradiacao gama tambem nao contribuiram para a degradacao do fungicida. O Prochloraz ficou retido principalmente na casca (media = 1,64 µg/g), que funcionou como barreira a contaminacao da polpa (media = 0,06 µg/g). O produto de degradacao, formado nas cascas das mangas tratadas na pos-colheita, foi identificado como sendo o BTS 44596. Os metabolitos, encontrados em niveis baixos, confirmaram a ocorrencia de baixa degradacao do fungicida em mangas. 14C-PROCHLORAZ RESIDUES IN IRRADIATED MANGOES Abstract The aim of this work was to evaluate the Prochloraz residual levels applied in mangoes, in pre and post-harvest after radiation treatment. The fruits were submitted to gamma radiation with of 1,0 kGy dose, aiming to verify if it induces the fungicide degradation. Treated post-harvest mangoes were stored, at 12 0C during 21 days. Prochloraz residues did not present reduction after safe period (21 days), established by the Brazilian legislation on agrochemicals. The refrigerated storage (12 0C) and the gamma radiation also did not contribute to the degradation of the fungicide. Prochloraz was mainly retained in the peels (mean = 1,64 µg/g) which served as barrier to the pulp (mean = 0,06 µg/g) contamination. The degradation product, formed in peels of post-harvest treated mangoes was the metabolite BTS 44596. The metabolites found in very low levels, confirm that low fungicide degradation occurs in mangoes.