Raw Data for Microplastic Identification and Quantification in Nile Tilapia and Milkfish from Public Markets in Makati City

Overview This dataset contains the primary raw monitoring data for the identification, characterization, and quantification of microplastics isolated from the gastrointestinal tract of Oreochromis niloticus L. (Nile Tilapia, n=20) and Chanos chanos L. (Milkfish, n=20). All 40 specimens were sourced from public markets in two selected public markets of Makati City, Philippines: Barangay Guadalupe and Barangay Poblacion. As a localized baseline study, this dataset establishes the initial food safety and environmental contamination benchmark for commercially sold fish within Makati City. Notably, analysis confirmed a zero count, complete absence of identifiable microplastic particles across all sampled groups during the collection period. Data Files and Structure The repository includes a standardized spreadsheet mapping out the sample collection and laboratory evaluation parameters across the following fields: • Sample Profile & Biometrics: Species designation (O. niloticus vs. C. chanos), specific sourcing market (Barangay Guadalupe or Barangay Poblacion), sample sizes (\(n=10\) per species per market), and corresponding individual biometric logs (total body weight and length). • Quantification Matrix: Total particle count logs and mean abundance calculations (particles per individual/tissue weight), uniformly reflecting Not Detected (ND) values across all 40 individual targets. • Characterization Parameters: Placeholders for morphological attributes (shape, color) and chemical composition, cross-verified as null/empty due to the absolute absence of recovered synthetic polymers. Methodology and Quality Control The gastrointestinal systems (specifically the esophagus and stomach) of the specimens were anatomically isolated. Organic tissue breakdown was achieved via Potassium Hydroxide (KOH) chemical digestion, followed by a secondary acid-hydroxide treatment and absolute filtration. Filter membranes underwent methanol washing and centrifugation to isolate potential residues. Final validation was performed via Attenuated Total Reflectance - Fourier-Transform Infrared (ATR-FTIR) Spectroscopy at the University of Makati facility to capture chemical fingerprints. Strict quality controls and clean-laboratory protocols were enforced to eliminate secondary ambient contamination. Potential Applications & Data Reuse This zero-count baseline dataset is highly valuable for: 1. Serving as an unpolluted baseline reference point for future urban environmental audits and longitudinal microplastic accumulation studies in Metro Manila public markets. 2. Supplying localized empirical control data for meta-analyses evaluating microplastic ingestion frequencies in aquaculture products across Southeast Asia. 3. Informing municipal food safety risk assessments and plastic-use mitigation policies managed by the Makati Local Government Unit (LGU) and local health departments.