Análise do potencial fitotóxico de lixiviado de aterro sanitário e esgoto doméstico: um estudo preliminar.

Abstract

The generation of effluents, such as landfill leachate and domestic sewage, has caused an imminent concern, since its toxic effects cause several negative impacts on the environment, in addition to being worrying from the point of view of public health. Thus, in this work, the objective was to investigate the toxic potential of landfill leachate and domestic sewage in the micro region of Sousa-PB using vegetable seeds. The methodology used consisted of carrying out monthly collections, during the months of November/2022 to January/2023, of leachate in the Sanitary Landfill in Sousa-PB and of domestic sewage in a gallery in the urban area of Pombal-PB. After collection, both effluents were characterized by means of physical-chemical and phytotoxicological tests, using plant seeds of Lactuta sativa (lettuce) as bioindicators. Finally, the determined data underwent statistical treatment. It was observed that the effluents, leachate and domestic sewage exerted toxic effects on the vegetable seeds studied, either in their diluted form or in natura. The leachate showed gradual toxicity as the concentration in the dilutions increased, decreasing the levels of germination and relative growth of the seeds. Although domestic sewage diluted at concentrations of 2, 4, 8, 16, 32 and 100% did not cause severe toxicity to the analyzed bioindicators, the tests showed a decrease in the Relative Seed Germination (GRS) and Relative Root Growth (CRR) indices. ). These results led to the conclusion that such effluents cannot be released directly into water resources, as well as reused in irrigation without prior treatment.