A Comprehensive Review on Microplastic in Beach Sediment

Microplastics (MPs) have been recognized as one of the biggest environmental challenges in marine ecosystems. Despite the extensive existing research knowledge on MPs, the origin, transport and deposition of MPs in beach sediment is still unclear. This review highlights the global occurrence, spatiotemporal distribution, sources, transport and accumulation of MPs on about 1700 world’s beaches, exploring the existing connotions on the influence of external mechanisms, internal mechanisms and local beach characteristics on MPs found in beach sediment. This review further highlights the challenges and future research potential of MPs in beach sediment. The review revealed 59.4% of studies were using "n/kg" as a unit, 30.8% using "n/m2" as a unit, and 9.8% using both units. Most paper on beach microplastics are published from Asia (45.1%) with India having a global percentage of 13.8. The summary of this review indicated that the distribution of microplactic abundance in beach sediment <100 n/kg (39.5%) and 100–500 n/kg (36.4%), 1000–5000 n/kg (12.3%), 500–1000 n/kg (6.8%) and >5000 n/kg (4.9%) with beaches in Africa, Asia, Europe and North America recorded high MP abundance (>1000 n/kg). This review clarifies the need to improve the research knowledge of MPs in beach sediment by creating a global database to access the existing threat; using a standard measuring method and unit for identification of results. Ultimately, we suggest the implementation of holistic management strategy for MP pollution in beach sediment, most importantly, by focusing on the elimination of fibre to drastically reduce the MP pollution.