Evaluation of the method by densimetry for the preliminary identification of microplastics in the Huallaga River
DOI:
https://doi.org/10.37711/repiama.2025.2.2.1Keywords:
plastic particles, optical microscopy, solid waste, exploratory sampling, saline flotation, water pollution, environmental monitoringAbstract
The pollution by microplastics represents an emerging environmental threat that affects the quality of aquatic ecosystems and human health. The need for an effective, economical, replicable analysis has become necessary to fill a critical information gap about these contaminants in urban freshwater bodies. The present study had as objective to evaluate the method by densimetry for the preliminary identification in surface waters of the urban section of the Huallaga River, Huánuco. Fifteen samples of surface water were collected, that also they were processed in laboratory through a saturated saline solution (320 g/L de NaCl), being duplicated experimentally to obtain thirty analytical units, and subsequently these were subjected to the decantation process during 72 hours.
The floating particles were observed under an optical microscope (40x) and a contextual visual analysis was performed. Particles with morphologies consistent with microplastics (fibers, fragments, and films) were identified, mainly in areas with sanitary discharges and accumulations of urban solid waste, where the highest frequency of findings was recorded. The application resulted to be effective, economical, and replicable, permitting a first characterization in real conditions with limited resources. It is concluded that densimetry is a viable technique for establishing preliminary baseline data and strengthening environmental monitoring strategies in regions without access to advanced analytical technologies.
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Copyright (c) 2025 Frans Emilio Minaya Rosales, Kelvy Alexander Yzaguirre Tinta, Alexandra Santos Almerco, Geraldine Valle Hurtado (Autor/a)
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