17 waste materials tested for stronger lower-carbon cement, including human hair and eggshells

Researchers tested 17 waste materials, including human hair, thermal receipts, fishing nets, and eggshells, as recycled aggregates in cement for a 2026 James Dyson Award project called Circular Design Cement. The idea is to replace some conventional aggregates with materials like glass, ceramics, and oyster shells, while using blast furnace slag cement to lower emissions. Cement production is a major source of CO2, so anything that cuts clinker use or diverts waste from landfill is worth watching. The project is still at the design and testing stage, and the article does not include strength test numbers or cost data. But if the results hold up, this approach could give builders a lower-carbon alternative without waiting for a completely new cement chemistry.