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Microplastics are emerging pollutants, formed through weathering, with sizes equal to or smaller than 5 mm. They can reach surface and groundwater sources, as well as oceans and seas through natural pathways or from the discharge of liquid effluents, causing immeasurable effects on human beings. This study aimed to evaluate the optimal conditions for the removal of polyethylene (PE) and expanded polystyrene (EPS) microplastics through coagulation and flocculation processes using aluminum sulfate. To achieve this goal, two 2² full factorial designs were employed, including two replicates at the central points. The sizes of the microplastics were fixed at 0.6 mm and 0.9 mm for PE and EPS, respectively. The selected independent variables were Al2(SO4)3 and pH. The experiments were conducted considering rapid mixing parameters (400 rpm for 1 min), slow mixing (100 rpm for 15 min), and sedimentation (30 min), with a velocity of 0.1 cm min⁻¹ in the Jar Test. Turbidity determination was applied to quantify the remaining microplastics. Consequently, it was observed that the highest efficiency occurred for PE microplastics at 4.25 mg L⁻¹ of Al2(SO4)3 and pH 5, and for EPS microplastics at 6.00 mg L⁻¹ of Al2(SO4)3 and pH 4, resulting in removal rates of 96.81% and 96.30% and turbidity levels of 0.38 and 0.50 NTU, respectively. The removal efficiencies of microplastics were similar, with a decrease at pH 6 for both, as low ionic strength prevents the release of H+ ions.

Objetivo: analisar o potencial de morbimortalidade por COVID-19 em comunidades quilombolas rurais. Métodos: estudo transversal, com 26 comunidades do Estado de Goiás. Utilizou-se o método Analytic Hierarchy Process (AHP) que hierarquiza critérios para estimar o índice de prioridade de morbimortalidade por COVID-19, sendo eles: sexo masculino, idade ≥ 60 anos, diabetes, câncer, hipertensão, tabagismo, dislipidemia e obesidade. Resultados: de 1.672 entrevistados, 52,0% eram homens, 19,0% ≥ 60 anos, 5,5% autor referiram diabetes, 19,6% hipertensão, 9,2% dislipidemia, 1,3% obesidade, 0,4% câncer e 13,9% tabagismo. Houve menor índice de prioridade na Comunidade Engenho 2, e maior em Buracão; sendo: idade ≥ 60 anos em Quilombo do Magalhães; sexo masculino em Kalunga dos Morros; diabetes e hipertensão em Tomás Cardoso; dislipidemia em Almeidas; obesidade em Buracão; câncer em Água Limpa; tabagismo em José de Coleto. Conclusão: houve diferentes potenciais de morbimortalidade por COVID-19, demonstrando qual comunidade apresenta maior/menor prioridade para ações estratégicas para enfrentamento da pandemia.