Journal Article

Characterization of Microplastics Pollution in Sea Surface Waters via Surface Trawling and Sediments of Davao Gulf, Philippines

Flores, James Phil D., Fuentes, Harold, Bacsarpa, Charmjill Y., Navidad, Lea G., Almerez, Queenie Lyn, Aquino, Eduardo, Benitez, Justine B., Capangpangan, Rey, Banda, Marybeth Hope

2026

Overview

Microplastics pollution in the Philippines presents significant risks to human health, food security and marine ecosystems. Davao Gulf, a biodiversity hotspot and vital fishing ground, is increasingly affected by this contamination. This study assessed the abundance and characteristics of microplastics in the gulf through sea surface water trawling and sediment sampling across multiple sites. Microplastics were detected in all samples, with average surface water concentrations of 0.097, 0.75 and 0.14 particles/m 3 for Trawls 1,2 and 3, respectively. Sediment concentrations averaged 15.55, 40.00 and 110.27 particles/kg at sites 1, 2 and 3, respectively. Microplastics exhibited diverse colors, morphologies and polymer types. Water samples displayed 12 color variants, predominantly white (31.34%), blue (14.43%), and black (14.10%), with fragments (41.21%) and films (30.15%) as dominant morphologies. Sediment samples showed seven color variants with brown (39.19%) and black (27.03%) prevalent, and filaments (32.43%) and fibers (24.32%) dominating. ATR-FTIR spectroscopy identified 31 polymer types in water and 12 in sediments. Polypropylene (51.41%), high-density polyethylene (21.15%) and polyethylene (5.97%) dominated in water, while azlon (33.78%) and rayon (24.32%) prevailed in sediments, indicating contributions from single-use plastics, packaging, household effluents and textile-based industries. These results highlight extensive microplastic pollution in Davao Gulf and emphasize the urgent need to upgrade wastewater treatment to capture even textile-based pollutants, promote sustainable materials and circular design, and implement coordinated regional monitoring and policies to mitigate microplastic pollution. Highlights Microplastics were detected in all sea surface trawl and sediment sampling sites from Davao Gulf. Color distribution of microplastics varied by environment with white dominant in water and brown in sediments. Surface waters were dominated by fragments and films while filaments and fibers prevailed in sediments. Polypropylene was the dominant polymer in surface water while azlon and rayon were prevalent in sediments. Microplastic distribution in Davao Gulf is strongly linked to riverine inputs with significant contributions from single-use plastics, packaging, household effluents and textile-related sources. Findings reveal diverse sources and physicochemical characteristics of microplastic pollution in the gulf, highlighting the urgent need for evidence-based, multi-level policy actions to protect marine ecosystems and dependent communities.

• Publisher: Springer International Publishing,Springer Nature B.V
• Subject: Biodiversity / Biodiversity hot spots / Color / Earth and Environmental Science / Ecosystems / Effluents / Endangered & extinct species / Environment / Environmental Engineering/Biotechnology / Environmental Management / Fibers / Filaments / Fishing zones / Food contamination / Food security / Fragments / Geoecology/Natural Processes / High density polyethylenes / Household wastes / Landscape/Regional and Urban Planning / Marine ecosystems / Microplastics / Morphology / Natural Hazards / Packaging / Pandemics / Plastic debris / Plastic pollution / Pollution detection / Polyethylene / Polymers / Polypropylene / Rayon / Research Paper / Rivers / Sampling / Sediment concentration / Sediment samplers / Sediments / Surface water / Sustainable materials / Trawling / Trawls / Waste management / Wastewater treatment / Water analysis / Water sampling / Wildlife conservation