Ecotoxicological analysis of glasses obtained from industrial residues using E. coli and S. aureus as bioindicators

This work deals with the study of the effect of coal ashes and industrial residues in the inertness of glasses designed for industrial uses. Five formulations with four factors (residues) and constraints were used according a mixture design. The residues were dried, sieved and mixed according to the design. The formulations were melted at 1450 °C during 2 h for stabilization using 10% wt of Na2CO3 (fluxing agent). The melts were cast into a refrigerated water mold and annealed at 600 °C, and thus, the glasses were analyzed regarding their ecotoxicological effect using the Agar Diffusion Test for Escherichia coli and Staphylococcus aureus as bioindicators, comparing the results with the Artemia sp. Acute Toxicity Test. The results were studied by analysis of variance in order to determine the individual influence of each residue in the inertness of the glass system. As a final result, the ecotoxicological analysis showed that the galvanic residue makes a non-inert glass due to the high iron and zinc content of this waste. The Agar Diffusion Test is a fast and accurate technique to determine the toxicity of glass systems only for high concentration samples.