Microplastic contamination in thirty commercially important fish species: Distribution, polymer composition, pollution indices, and human health risks.

Marine pollution bulletin · 2026 · Unclear · Low evidence

← Research stream

UnclearLow evidencePaper 2

Study snapshot

PublicationMarine pollution bulletin · 2026

Study typeexposure_assessment

Reported directionUnclear

Evidence ratingLow

Abstract

This study investigated the occurrence, distribution, and polymer composition of MP in 30 commercially important fish species (N = 600 specimens) collected from three major landing centres along the Thoothukudi coast from December 2024 to May 2025. Employing hydrogen peroxide digestion and ATR-FTIR spectroscopy for particle identification. Extracted MPs were identified based on their molecular composition, with a library match of >80%. MP concentrations varied significantly among species (p < 0.05), with the highest accumulation in the gastrointestinal tract (3.67-8.75 particles/fish), followed by gills (1.93-4.27 particles/fish) and muscle tissue (1.2-3.6 particles/5 g wet weight). Carnivorous species exhibited significantly higher MP burdens than planktivorous species, with Epinephelus longispinis showing maximum gut contamination (8.75 ± 2.36 particles/fish). Among 1446 particles analyzed, polyethylene (37.47%) and polypropylene (27.20%) dominated polymer composition, with fibers comprising 85% of particle morphology. A human health risk assessment revealed that estimated daily intake values ranged from 0.047 to 0.159 particles/kg body weight/day. The pollution risk (PRI) and hazard index (PHI) of most analyzed fish species ranged from 335 to 668 and 265 to 302, indicating considerable to medium hazard risk. These findings demonstrate widespread MP contamination across trophic levels in Thoothukudi's marine ecosystem, highlighting urgent needs for targeted pollution mitigation strategies and continued monitoring of MP bioaccumulation in commercially harvested fish species to protect both ecosystem integrity and human food security.

Machine Enhanced Logic

AI evidence extraction

Structured fields below were generated from the paper’s abstract and metadata to make the evidence easier to inspect. Automated extraction may be incomplete or incorrect; verify important details against the original paper.

Study typeexposure_assessment

Effect directionunclear

Population30 commercially important fish species collected from three major landing centres along the Thoothukudi coast

Sample size600

ExposureDecember 2024 to May 2025

Evidence strengthLowConfidence: 74% · Peer reviewed: yes

Main findings

Microplastics were detected across 30 fish species, with highest concentrations in the gastrointestinal tract (3.67–8.75 particles/fish), followed by gills (1.93–4.27 particles/fish) and muscle (1.2–3.6 particles/5 g wet weight). Among 1446 particles analyzed, polyethylene (37.47%) and polypropylene (27.20%) were most common and fibers comprised 85%; estimated daily intake ranged from 0.047 to 0.159 particles/kg body weight/day, and most species had PRI 335–668 and PHI 265–302 (considerable to medium hazard risk).

Outcomes measured

Microplastic (MP) occurrence and concentration in fish tissues (gastrointestinal tract, gills, muscle)
Polymer composition of MPs (ATR-FTIR identification)
Particle morphology (e.g., fibers)
Estimated daily intake (EDI) of MPs for humans
Pollution risk index (PRI)
Pollution hazard index (PHI)

Limitations

Study location limited to three landing centres along the Thoothukudi coast
Sampling period limited to December 2024–May 2025
MP identification relied on ATR-FTIR with library match threshold >80% (as stated), which may affect classification for lower-match particles

View raw extracted JSON

{
  "study_type": "exposure_assessment",
  "exposure": {
    "band": null,
    "source": null,
    "frequency_mhz": null,
    "sar_wkg": null,
    "duration": "December 2024 to May 2025"
  },
  "population": "30 commercially important fish species collected from three major landing centres along the Thoothukudi coast",
  "sample_size": 600,
  "outcomes": [
    "Microplastic (MP) occurrence and concentration in fish tissues (gastrointestinal tract, gills, muscle)",
    "Polymer composition of MPs (ATR-FTIR identification)",
    "Particle morphology (e.g., fibers)",
    "Estimated daily intake (EDI) of MPs for humans",
    "Pollution risk index (PRI)",
    "Pollution hazard index (PHI)"
  ],
  "main_findings": "Microplastics were detected across 30 fish species, with highest concentrations in the gastrointestinal tract (3.67–8.75 particles/fish), followed by gills (1.93–4.27 particles/fish) and muscle (1.2–3.6 particles/5 g wet weight). Among 1446 particles analyzed, polyethylene (37.47%) and polypropylene (27.20%) were most common and fibers comprised 85%; estimated daily intake ranged from 0.047 to 0.159 particles/kg body weight/day, and most species had PRI 335–668 and PHI 265–302 (considerable to medium hazard risk).",
  "effect_direction": "unclear",
  "limitations": [
    "Study location limited to three landing centres along the Thoothukudi coast",
    "Sampling period limited to December 2024–May 2025",
    "MP identification relied on ATR-FTIR with library match threshold >80% (as stated), which may affect classification for lower-match particles"
  ],
  "evidence_strength": "low",
  "confidence": 0.74,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "microplastics",
    "fish",
    "Thoothukudi coast",
    "ATR-FTIR",
    "polyethylene",
    "polypropylene",
    "fibers",
    "gastrointestinal tract",
    "gills",
    "muscle",
    "estimated daily intake",
    "pollution risk index",
    "hazard index"
  ],
  "suggested_hubs": []
}

AI can be wrong. Always verify against the paper.

AI-extracted fields are generated from the abstract and metadata and may be incomplete or incorrect. This material is for informational purposes and is not medical advice.

Identifiers and source

DOI: 10.1016/j.marpolbul.2026.119360
PubMed: 41650713

Read the original paper →

Related papers

← Back to the Research Library