Chemical and mineral composition of fly ashes from home furnaces, and health and environmental risk related to their presence in the environment

Abstract

The study presents the results of an analysis of fly ashes produced from burning of solid fuels mixed with municipal waste and assesses the environmental and health risk associated with infiltration of the selected metals to the environment. The phase composition suggests that the material is extremely mixed and diverse. Low-temperature components were mixed with substances formed in high temperatures. The variable composition of waste from different home furnaces with high content of the amorphous phase (which dissolves in water more easily than its crystalline equivalents) may be harmful to the environment and for the people. The dominant elements were silicates and aluminosilicates, such as: quartz, feldspar and plagioclase (albite). Clay minerals (kaolinite and mullite), carbonates (calcite), oxides/oxidehydroxides of iron and sulfate minerals (gypsum and anhydrite) were also abundant. The particles' major constituents were Si, Al, Ca and Fe oxides (85.5%), while S, Mg, Na, K and Ti oxides accounted for 12.6% of the total content. The risk assessment code suggested: Low Risk for As, Co, Cr, Ni, Medium Risk for Cd, Cu and Pb, and High Risk for Zn. Hazard Index (HI) calculated for non-cancerogenic substances for children was 2.35E+00. The total Risk index for children was 4.88E-05. As for adults, HI was 2.42E-01 for women, and 2.89E-01 for men, while the Risk index value was 6.85E-05 for women, and 8.48E-05 for men. The value HI > 1 points to the risk of adverse health impact on children exposed to fly ashes.