Microplastics in the form of fiber can form knots or clumps and can be dangerous because fiber can block the digestive tract and block the passage of food. When plastic particles accumulate in large quantities in the intestines of small animals, they may have the same effect as large plastic waste and clog the digestive system (Hoss & Settle 1990). The accumulation of waste in the digestive tract can cause a false feeling of fullness. This causes the fish to experience a decrease in appetite (Ryan 1988). There is also concern that if ingested by organisms, small items of plastic waste might facilitate the transport of chemical contaminants.
In addition, microplastics can function as pathogenic factors, potentially bringing microbial species to waters, microplastics that have contaminated biota at various trophic levels, there is concern that debris from plastics or lower. Furthermore, organisms of lower trophic levels are consumed, biomagnification has the potential to occur at higher trophic levels, this will affect human health (Rochman, et al., 2015).
