Investigation of microplastics as emerging contaminants in sources and health effects on humans, review study

In recent years, environmental contamination with plastics has become one of the biggest concerns of various communities. Microplastics (MPs) are plastics less than 5 mm in size. MPs remain in the environment for thousands of years without decomposing. However, accurate analytical methods for the detection and characterization of MPs are scarce. In this descriptive-review study, based on the studies of various researchers and the papers of recent years, this contamination has been introduced and its adverse effects on human health and different environments have been discussed. The results of the studies have shown that microplastic contamination of salt has been reported significantly between four different sources: sea salt 0-1674, lake salt 8-468 and well rock salt 0-204 microplastic per kg (MPs/kg). The number of MPs in untreated water is 1437±34 to 3605±497 particles per liter and in general, the amount of microplastics in treated water is about 83% less than untreated water generally. The length and diameter should be considered when reporting the presence of MPs because the diameter is significant for respiration, while length plays a vital in durability and toxicity. Although the adverse health effects of microplastics have not been fully revealed, but the transfer of chemicals from microplastics to living organisms is a significant concern, and a better understanding of the potential dangers of microplastics is essential to human health.