Chemical analysis of marine microdebris pollution in macroalgae from the coastal areas of Argentina

Abstract

Marine microdebris (MDs, < 5 mm) and mesodebris (MesDs, 5 – 25 mm), consist ofvarious components, including microplastics (MPs), antifouling or anticorrosive paintparticles (APPs), and metallic particles (Mmps), among others. The accumulation ofthese anthropogenic particles in macroalgae could have significant implications withincoastal ecosystems because of the role of macroalgae as primary producers and theirsubsequent transfer within the trophic chain. Therefore, the objectives of this studywere to determine the abundance of MDs and MesDs pollution in different species ofmacroalgae (P. morrowii, C. rubrum, Ulva spp., and B. mínima) and in surface watersfrom the Southwest Atlantic coast of Argentina to evaluate the ecological damage. MDsand MesDs were chemically characterized using μ-FTIR and SEM/EDX to identify, andassess their environmental impact based on their composition and degree of pollutionby MPs, calculating the polymer hazard index (PHI). The prevalence of MDs washigher in foliose species, followed by filamentous and tubular ones, ranging from 0 to1.22 items/g w.w. for MPs and 0 to 0.85 items/g w.w. for APPs. It was found thatmacroalgae accumulate a higher proportion of high-density polymers like PAN andPES, as well as APPs based on alkyd, PMMA, and PE resins, whereas apredominance of CE was observed in waters. Potentially toxic elements, such as Cr,Cu, and Ti, were detected in APPs and MPs, along with the presence of epiplasticcommunities on the surface of APPs. According to PHI, the presence of high hazardscore polymers, such as PAN and PA, increased the overall risk of MP pollution inmacroalgae compared to surrounding waters. This study provided a baseline for MDsand MesDs abundance in macroalgae as well as understanding the environmentalimpact of this debris and their bioaccumulation in the primary link of the coastal trophicchain.