O uso de praguicidas nas atividades aqüícolas: destino e efeitos após aplicações em tanques experimentais e avaliação nas pisciculturas e pesqueiros da bacia do rio Mogi-Guaçu
Data
2017-11-15
Autores
Título da Revista
ISSN da Revista
Título de Volume
Editor
Biblioteca Digital de Teses e Dissertações da USP
Universidade de São Paulo
Escola de Engenharia de São Carlos
Universidade de São Paulo
Escola de Engenharia de São Carlos
Resumo
Descrição
O uso de praguicidas vem sendo a principal forma de combater os ectoparasitas dos viveiros de peixes, sendo que os mais utilizados na bacia do rio Mogi-Guaçu são o diflubenzuron (DFB), e os organofosforados paration metílico (PM) e triclorfon (TCF), cujo principal subproduto é o diclorvós (DDVP). O uso indiscriminado destas substâncias nos cultivos de peixes pode ocasionar danos aos ecossistemas aquáticos que recebem os efluentes dos tanques comprometendo a qualidade ambiental, além de representar risco aos consumidores destes pescados. Conhecer o padrão de acumulação destes praguicidas, bem como o efeito em espécies não-alvo são fundamentais para a correta gestão desta atividade. Foram analisadas quanto à presença de DFB (CLAE-DAD), PM e DDVP (CG-NPD), amostras de água, sedimentos e peixes (Oreochromis niloticus) coletadas em três pesqueiros do município de Socorro, SP (junho de 2005) e em 4 tanques experimentais (10.000 L de água, 10 cm de sedimento arenoso, localizados no CRHEA - USP, Itirapina, SP) os quais foram utilizados num experimento de simulação de tratamento contra ectoparasitas de peixes (junho a agosto de 2005). Neste caso, antes e após uma única aplicação das formulações Dimilin (1,0 g/\'M POT.3\' DFB), Folisuper (0,25 g/\'M POT.3\' PM) e Neguvon (0,25 g/\'M POT.3\' TCF), amostras de água sedimentos, peixes e comunidades fitoplanctônica, zooplanctônica e de macroinvertebrados bentônicos foram coletadas nos tempos zero, 5 horas, 1, 2, 5 e 7 dias após as aplicações. Não foram detectados resíduos dos praguicidas em nenhuma das amostras coletadas nos três pesqueiros do município de Socorro, SP. Foram detectados resíduos nos compartimentos e efeitos nos grupos de organismos analisados nos tanques experimentais. O DFB é persistente nos compartimentos água e sedimentos, assim como o PM o qual possui menor persistência. O DDVP não é persistente nestes compartimentos. Houve acúmulo de DFB e PM nos filés de peixes submetidos ao tratamento com Dimilin e Folisuper, respectivamente, em todos os tempos amostrados. Estes valores excederam os limites máximos recomendados para alimentos segundo o Codex Alimentarius. As aplicações dos praguicidas causaram efeitos na composição e densidade das comunidades biológicas os quais variaram em função do produto aplicado e do tempo de exposição. De maneira geral, os macroinvertebrados bentônicos foram mais sensíveis aos organofosforados, enquanto que o zooplâncton foi mais sensível ao DFB. Os cladóceros mostraram alto grau de sensibilidade para todos os praguicidas aplicados. Com relação à comunidade fitoplanctônica, aparentemente os praguicidas causaram efeitos indiretos na composição e densidade deste grupo.
The use of pesticides has been the foremost course of action to combat the ectoparasites of farmed fee fishes, in which diflubenzuron (DFB) and the organophosphates methyl parathion (PM) and trichlorfon (TRC) (witch the main sub product is dichlorvos - DDVP) are the most widely used in the Mogi-Guaçu river catchments. The indiscriminate use of such compounds on aquaculture can cause damage to the aquatic ecosystems that receive the pond\'s effluents, hence endangering environmental quality and consumer\'s health. The knowledge of understanding the environmental fate, accumulation rate, as well as their effect upon non-target species, is particularly important for the correct aquaculture management. Samples of water, sediments and fishes (Oreochromis niloticus) from three fee fishing enterprises from Socorro, SP, Brazil (June, 2005), were analyzed to verify residues of DFB (HPLC-DAD), PM and DDVP (GC-NPD). In addition, four experimental ponds (10.000 L, 10 cm of sediment, localized on CRHEA - USP, Itirapina, SP, Brazil) were used to simulate a treatment against fish ectoparasites (June to August, 2005). In this case, before and after a single application of Dimilin (1,0 g/\'M POT.3\' DFB), Folisuper (0,25 g/\'M POT.3\' PM) and Neguvon (0,25 g/\'M POT.3\' TCF), samples of water, sediments, fishes, phytoplankton, zooplankton and benthonic macro invertebrates were collected on zero, 5 hours, 1, 2, 5 and 7 days after contamination. No pesticides residues in the samples of the three fee fishing enterprises from Socorro were detected. Pesticides residues in the compartments and effects in all of the organism groups analyzed were detected on the experimental ponds. The DFB is persistent in water and sediments, as well as the PM, which was comparatively less persistent. However, DDVP is not persistent on those compartments. There was DFB and PM accumulation on fish filets subjected to treatment with Dimilin and Folisuper, respectively, which were detected in all sampled times. These values exceed maximal level limits proposed by the Codex Alimentarius. The pesticides applications caused effects on the biological community composition and density, which varied due to the formulation applied and time exposition. Overall, the benthonic macro invertebrates were more sensitive to organophosphorates, while zooplankton were more sensitive to DFB. The cladocerans indicated high degree of sensitivity to all pesticides applied. With respect to phytoplankton, apparently, pesticides caused only indirect effects upon the composition and density of this group.
The use of pesticides has been the foremost course of action to combat the ectoparasites of farmed fee fishes, in which diflubenzuron (DFB) and the organophosphates methyl parathion (PM) and trichlorfon (TRC) (witch the main sub product is dichlorvos - DDVP) are the most widely used in the Mogi-Guaçu river catchments. The indiscriminate use of such compounds on aquaculture can cause damage to the aquatic ecosystems that receive the pond\'s effluents, hence endangering environmental quality and consumer\'s health. The knowledge of understanding the environmental fate, accumulation rate, as well as their effect upon non-target species, is particularly important for the correct aquaculture management. Samples of water, sediments and fishes (Oreochromis niloticus) from three fee fishing enterprises from Socorro, SP, Brazil (June, 2005), were analyzed to verify residues of DFB (HPLC-DAD), PM and DDVP (GC-NPD). In addition, four experimental ponds (10.000 L, 10 cm of sediment, localized on CRHEA - USP, Itirapina, SP, Brazil) were used to simulate a treatment against fish ectoparasites (June to August, 2005). In this case, before and after a single application of Dimilin (1,0 g/\'M POT.3\' DFB), Folisuper (0,25 g/\'M POT.3\' PM) and Neguvon (0,25 g/\'M POT.3\' TCF), samples of water, sediments, fishes, phytoplankton, zooplankton and benthonic macro invertebrates were collected on zero, 5 hours, 1, 2, 5 and 7 days after contamination. No pesticides residues in the samples of the three fee fishing enterprises from Socorro were detected. Pesticides residues in the compartments and effects in all of the organism groups analyzed were detected on the experimental ponds. The DFB is persistent in water and sediments, as well as the PM, which was comparatively less persistent. However, DDVP is not persistent on those compartments. There was DFB and PM accumulation on fish filets subjected to treatment with Dimilin and Folisuper, respectively, which were detected in all sampled times. These values exceed maximal level limits proposed by the Codex Alimentarius. The pesticides applications caused effects on the biological community composition and density, which varied due to the formulation applied and time exposition. Overall, the benthonic macro invertebrates were more sensitive to organophosphorates, while zooplankton were more sensitive to DFB. The cladocerans indicated high degree of sensitivity to all pesticides applied. With respect to phytoplankton, apparently, pesticides caused only indirect effects upon the composition and density of this group.
Palavras-chave
Pesqueiros, Praguicidas, Piscicultura, Inseticidas, Mogi-Guaçu, Pesticidas, Pesticides, Aquaculture, Insecticides, Fish farm, Fee fishing enterprises, Recreational fishing