A contaminação por chumbo no município de Boquira/BA como tema norteador para o ensino de química, sob a luz da abordagem CTS.

Abstract

The present research aims to analyze the application of a Didactic Sequence (SD) for the Teaching of Chemistry at the Colégio Estadual de Boquira (CEB) based on the case of lead (Pb) contamination in the municipality, in the light of the CTS approach. Between the 1950s and 1990s, intense mining activity occurred in the municipality of Boquira/BA, which had several impacts on the municipality's sovereignty. Among the impacts, the inadequate disposal of mineral waste in the open air in the rural area of the municipality, a place popularly known as the “Tails Basin”, stands out. In this area, concentrations of the flagship element of this work, lead, are alarming and are above the guiding values considered limits of CONAMA resolution 420/2009 for residential areas, as exemplified in studies carried out by Bertolino et al. (2014), Cunha et al. (2016) and Paes (2022). Thinking about this environmental liability in which the municipality of Boquira/BA lives, we planned an SD for Chemistry Teaching at CEB with an emphasis on discussions about social, environmental, human and ethical aspects involving the extinct Mine of Boquira/BA, linked to the introduction of chemical concepts in class. To do this, we use basic aspects of the nature of the qualitative approach to meet the objectives initially outlined. Qualitative research was applied through sequential pedagogical interventions focused on the constant search for aspects specific to chemical information that can be linked to education for citizenship training. SD was applied in four stages in which each stage had its own objectives that dialogued with Chemical science and the CTS approach in accordance with the developments in the case of lead contamination in the municipality of Boquira/BA. The application of SD occurred through discussions focused on historical, social, geographic and environmental aspects of Mineração Boquira S/A, through argumentative discursive classes, field classes (technical visits) and classes on the direct application of science in the social environment, such as the stage of carrying out experimental activities in the classroom, aimed at articulating science and civic education. As a result, we realized that the SD applied enabled the insertion and discussion of several chemical concepts in the classroom, exemplifying that the case of lead contamination in Boquira/BA is an excellent guiding theme for Chemistry Teaching, in the light of the CTS approach, especially because it manages to mediate between aspects specific to the nature of science aimed at direct application to the social environment, highlighting scientific work as a socially constructed activity. The SD analysis also allowed us to observe the relevance of the CTS approach for studies like this, in addition to showing us the potential limitations of SD, which allows for better discussions and developments in future studies.