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Our study examines how volcanic ash layers affect Earth's environment and climate, focusing on carbon, cadmium, and sulfur changes in deep-sea sediment from the Toba super eruption 74,000 years ago. This eruption, the largest of the Quaternary period, released 2,800 cubic kilometers of material and sulfur dioxide, which formed sulfate aerosols, potentially causing a volcanic winter. In sediment core RC14-37, we found a 15 cm thick Toba ash layer at 100-115 cm depth, with the highest ash concentration at 102-104 cm, significantly diluting the sulfur signal from 102-106 cm and masking the sulfur peak. Elevated sulfur levels just below the top of the ash layer suggest rapid deposition after most ash settled, with levels decreasing towards the base, indicating additional atmospheric sulfur. We used X-ray fluorescence (XRF) to measure sulfur and cadmium content. High cadmium levels in the ash layers suggest increased marine productivity. The SiO2 content in the ash ranged from 66% to 78%. Given that Toba ash contains 12 ppm sulfur, our corrected sulfur content (1700-3100 ppm) suggests most sulfur came from atmospheric sulfate aerosols. These results indicate increased biological productivity and sulfur in the ash layers, providing insights into the eruption's ecological impacts.