Microplastics are widely present in marine environments, with sediments acting as major sinks. This review evaluates current extraction techniques, microplastic occurrence and distribution in sediments, and their potential adverse effects on marine organisms. Over 100 studies from the last 50 years were analyzed, highlighting the need for standardized techniques, unified reporting units, and more realistic effect assessments. Microplastics are categorized into primary (e.g., pellets, microbeads) and secondary (degraded plastic) types. They range in size from micrometers to millimeters, with a commonly accepted definition of <5 mm. Microplastics are found in sediments worldwide, with their distribution influenced by factors such as density, biofouling, and environmental conditions. Sampling and extraction techniques vary, leading to inconsistencies in reported concentrations. The lack of a standardized size definition and reporting units complicates comparisons between studies. Sediments are suggested to be long-term sinks for microplastics, with biofouling contributing to their settling. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Sampling techniques differ, leading to varied reporting units. Extraction methods include density separation using salt solutions to isolate microplastics. Microplastics are found in sediments worldwide, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics areMicroplastics are widely present in marine environments, with sediments acting as major sinks. This review evaluates current extraction techniques, microplastic occurrence and distribution in sediments, and their potential adverse effects on marine organisms. Over 100 studies from the last 50 years were analyzed, highlighting the need for standardized techniques, unified reporting units, and more realistic effect assessments. Microplastics are categorized into primary (e.g., pellets, microbeads) and secondary (degraded plastic) types. They range in size from micrometers to millimeters, with a commonly accepted definition of <5 mm. Microplastics are found in sediments worldwide, with their distribution influenced by factors such as density, biofouling, and environmental conditions. Sampling and extraction techniques vary, leading to inconsistencies in reported concentrations. The lack of a standardized size definition and reporting units complicates comparisons between studies. Sediments are suggested to be long-term sinks for microplastics, with biofouling contributing to their settling. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Sampling techniques differ, leading to varied reporting units. Extraction methods include density separation using salt solutions to isolate microplastics. Microplastics are found in sediments worldwide, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are found in sediments globally, with concentrations varying by location and environmental factors. Microplastics are