Composition and abundance of microplastics in surface sediments and their interaction with sedimentary heavy metals, PAHs and TPH (total petroleum hydrocarbons)

The composition and abundance of microplastics (MPs) and concentrations of heavy metals, PAHs and TPH in surface sediments as well as their relationship with the number of MPs in three contrasting sediment types were investigated in Bandar Abbas, Iran. Total number of MPs ranged from 3542 to 33561 items per m(2) in different stations. The collected MPs displayed a variety of shapes and colors. White filaments were the most dominant MP item in the Khor-e-Yekshabeh and Suru stations while blue fragments were dominant items in the Gorsozan. Concentrations of heavy metals, PAHs and TPH also varied among stations. There were significant correlations between the total number of MPs, sediment grain size and ten measured heavy metals (P < 0.05). In contrast, no significant correlations were detected with PAHs (except for Benzo (a) ant) and TPH concentrations (P > 0.05). MPs in sediment as vectors for heavy metals and some PAHs can ingest by benthic animals, resulting in their bioaccumulation in marine food web.