Multi-Species Bioaccumulation and Risk Assessment of Heavy Metals in a Tropical Industrial Coastline: Sentinel-Based Insights from the Philippines

Montejo, April Joy; Roa, Elnor C.; Besoña, Jomar N; Dela Torre, Christian N; Coñado, Jade N; Guia, Reycyl G; Olbenario, Margie Rose N; Perpetua, Aida D; Vedra, Sonnie A; Capangpangan, Rey Y

doi:10.22059/poll.2026.407688.3229

Multi-Species Bioaccumulation and Risk Assessment of Heavy Metals in a Tropical Industrial Coastline: Sentinel-Based Insights from the Philippines

Articles in Press

Document Type : Original Research Paper

Authors

April Joy Montejo ¹

Elnor C. Roa ²

Jomar N Besoña ³

Christian N Dela Torre ⁴

Jade N Coñado ⁴

Reycyl G Guia ⁴

Margie Rose N Olbenario ⁴

Aida D Perpetua ⁴

Sonnie A Vedra ⁴

Rey Y Capangpangan ⁵

¹ Department of Environmental Science, Mindanao Stat University at Naawan

² Mindanao State University at Naawan - College of Fisheries and Life Sciences

³ Mindanao State University at Naawan - College of Fisheries and Marine Sciences

⁴ Mindanao State University at Naawan - College of Environment and Life Sciences

⁵ Mindanao State University at Naawan - College of Fisheries and Marine Science

10.22059/poll.2026.407688.3229

Abstract

This research applies an integrated biomonitoring framework that combines bioaccumulation metrics (BSAF, BAF) and toxicological risk indices (EDI, HI) to assess heavy metal contamination (Pb, Cd, and Hg) along a tropical industrial coastline in Iligan City, Philippines. Multi-trophic bioindicators (Anadara sp., Terapon jarbua, and Padina sp.) were analyzed across three coastal sites to trace sediment-associated and waterborne exposure pathways. Pb exhibited distinctive accumulation patterns, with sediment concentrations ranging from 5.37 to 5.43 mg/kg, closely matching those detected in Anadara sp. (5.40–5.79 mg/kg) and exceeding the levels observed in T. jarbua (2.33–3.38 mg/kg). This affirms its role as an effective sentinel for sediment-associated Pb exposure and highlights the link between sediment and biota. Significant differences among environmental compartments (Kruskal-Wallis, p < 0.05) further indicate pathway-specific uptake, with bivalves linked to sediment exposure and fish reflecting mixed trophic and waterborne inputs. Risk assessment showed higher exposure in Anadara sp. (HQ = 0.206) than in T. jarbua (HQ = 0.183), with bivalve concentrations exceeding Philippine regulatory limits but remaining within EU thresholds. Despite this, HQ values <1 indicate no immediate non-carcinogenic risk under current consumption assumptions. Cd and Hg were below detection limits, including in the macroalgae sample, Padina sp., identifying Pb as the primary contaminant of concern. By integrating bioaccumulation and exposure metrics, this research provides a systems-based framework for tracing contaminant pathways and assessing seafood safety in rapidly urbanizing tropical coastal systems.

Keywords

seafood safety

industrial exposure

trophic transfer

bioindicator species

Iligan City

Subjects