Construção e utilização de projeto de Wetland indoor para mitigação dos efeitos citotóxicos de solução de bituca de cigarro

Abstract

Cigarette butts are among the most common and overlooked solid waste in terms of environmental impact. Once improperly discarded, they release toxic substances such as trace metals, nicotine, tar, among others, which can cause environmental damage due to their toxicity. Considering their chemical composition and the effects they have on ecosystems, the search for sustainable solutions to this issue becomes necessary. In this context, the aim of this study was to evaluate the effectiveness of an indoor constructed Wetland system using the macrophyte Eichhornia crassipes (water hyacinth) for the phytoremediation of solutions contaminated by cigarette butts. The experiment was conducted over 37 days, using leachate solution concentrations of 25%, 50%, and 100%, in addition to a negative control (distilled water) and a reference group (leachate without plants). The development of the plants in the system was monitored weekly through parameters such as weight measurement, bulb diameter measurement, bulb count, and individual flowering. Analyses were carried out before and after phytoremediation, including tests of physicochemical parameters (using a multiparameter probe) and bioassays with Allium cepa [test methodology based on Fiskesjö (1985) and slide preparation according to Guerra (2002)]. After treatment in the Wetland system, a significant improvement was observed in all physicochemical parameters, including increased dissolved oxygen and redox potential, reduced electrical conductivity and total dissolved solids, as well as an improvement in solution pH. The A. cepa results showed that after treatment in the wetland system, there was an increase in root length, a rise in the mitotic index, and a significant reduction in nuclear and chromosomal alterations, as well as in the frequency of micronuclei. It is concluded that phytoremediation using Eichhornia crassipes in an indoor wetland system is an effective and low-cost alternative for mitigating the environmental impacts caused by the improper disposal of cigarette butts, with the choice of water hyacinth justified by its high capacity for absorbing toxic compounds and rapid growth, characteristics confirmed in this study.