Marine plastic pollution represents a critical environmental challenge, with millions of tons of plastic waste entering the oceans annually and threatening ecosystems, biodiversity, and human health. This systematic review evaluates the current state of the art in recycling and reusing marine plastic waste within the architecture, engineering, and construction (AEC) sectors, following the PRISMA methodology. Sixty-six peer-reviewed articles published between 2015 and 2025 were analysed, focusing on the integration of plastic waste. The review identifies mechanical recycling as the predominant method, involving washing and shredding plastics into fibres or flakes for use in cementitious composites, asphalt modifiers, bricks, panels, and insulation. Results indicate that recycled plastics, such as PET, HDPE, and PP, can enhance thermal insulation, water resistance, and flexural strength in non-structural applications. However, challenges persist regarding compressive strength, fibre dispersion, and chemical compatibility with cementitious matrices. Although the reuse of marine plastics supports circular economy goals by diverting waste from oceans and landfills, significant gaps remain in long-term durability, microplastic release, end-of-life recyclability, and comprehensive environmental assessments. The findings underscore the need for further research on the broader adoption of life cycle analysis, as well as long-term durability and environmental contamination analyses.

The objective of this research is focused on 3D printing techniques using natural materials in the construction sector. Digital fabrication has captured widespread attention for its remarkable ability to craft parametric and complex geometry with relative ease. Beyond its technical prowess, this process holds great potential in addressing two pressing issues: waste management and carbon emissions, to reduce costs and environmental impacts. This study assesses the eco-efficiency of 3D printing with earthen composites compared to conventional construction materials in large-scale Robotic fabrication, employing the life cycle assessment (LCA) framework to quantify the environmental impacts of materials suitable for 3D printing. An eco-efficiency analysis was employed to aggregate the results of LCA into a single framework to assist in decision-making by selecting the most optimized and eco-efficient alternative. The findings indicate that shell structures built using additive manufacturing and 3D printed materials can be better optimized for efficiency. This paper comprehensively examines 3D printing with earth materials, focusing particularly on biocomposites, byproducts, and direct extrusion printing methods. Comparative analysis highlights the materials, processes, and industries driving these advancements. There has been a surge of interest in reinforcing 3D-printed structures with natural fibres and additives. A significant aspect of this study explores how 3D printing, especially when utilizing natural materials and byproduct-based composites, can contribute positively to the environment.