Chromium in cement and concrete often comes from industrial waste products like slag and fly ash used as supplementary cementitious materials or from the natural constituents of raw materials. Chromium exists in several oxidation states, but the hexavalent form (Cr(VI)) is the most concerning due to its toxicity and potential health risks. In the hydration process of cement, chromium can influence the setting time and overall durability of the concrete. It reacts with other elements in the cement mix to form stable compounds, some of which can affect the properties of the hardened concrete.