Pollution

Pollution

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

Document Type : Original Research Paper

Authors
1 College of Environment and Life Sciences, Mindanao State University at Naawan, Misamis Oriental, 9023, Philippines
2 College of Fisheries and Marine Sciences, Mindanao State University at Naawan, Misamis Oriental, 9023, Philippines
Abstract
This research applies an integrated biomonitoring framework that combines bioaccumulation metrics (BSAF, BAF) and toxicological risk indices (EDI, HQ) 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
Subjects

Alburo, R. P., and Villegas, L. M. G. (2025). Ecological risk assessment of heavy metal pollution in surface water and sediment of Lahug River, Cebu, Philippines. ASEAN Journal of Scientific and Technological Reports, 28(3), e257492. https://doi.org/10.55164/ajstr.v28i3.257492 
Adani, P., Sawale, A.A., and Nandhagopal, G. (2022). Bioaccumulation of heavy metals in the food components from water and sediments in the coastal waters of Kalpakkam, Southeast coast of India. Environ. Nanotechnol. Monit. Manage., 17, 100627. https://doi.org/10.1016/j.enmm.2021.100627 
Afzaal, M., Hameed, S., Liaqat, I., Khan, A., Manan, H. A.et al. (2022). Heavy metals contamination in water, sediments and fish of freshwater ecosystems in Pakistan. Water Pract. Technol., 17(5), 1253–1272. DOI: 10.2166/wpt.2022.039
Algul, F., and Beyhan, M. (2020). Concentrations and sources of heavy metals in shallow sediments in Lake Bafa, Türkiye. Sci. Rep., 10, 11782.
Arnot, J. A., and Gobas, F. A. (2006). A review of bioconcentration factor (BCF) and bioaccumulation factor (BAF) assessments for organic chemicals in aquatic organisms. Environ. Rev., 14(4), 257–297.
Authman, M. M. N., Zaki, M., Khallaf, E., and Abbas, H. (2015). Use of fish as bio-indicators of the effects of heavy metal pollution. J. Aquac. Res. Dev., 6, 328.
Balingit, R., Tampus, A., Pedrosa-Gerasmio, I., Marecen-Pates, M., and Bersaldo, M. (2024). Bioaccumulation of heavy metals and health risk assessment of the mangrove clam, Pegophysema philippiana (Reeve, 1850), in Davao region, Philippines. AACL Bioflux, 17(1).
Bureau of Fisheries and Aquatic Resources (BFAR). (2015). Fisheries Administrative Order No. 233 – Guidelines on the sampling and analysis of water and sediment quality for monitoring of fisheries. (Quezon City: BFAR)
Burkhard, L. (2009). Estimation of Biota Sediment Accumulation Factor (BSAF) from paired observations of chemical concentrations in biota and sediment. U.S. EPA Report, EPA/600/R 06/047. Ecological Risk Assessment Support Center, Cincinnati, OH.
Castañeto, A. M. B., and Lacuna, M. L. D. G. (2015). Coastal zooplankton in the waters of Iligan City, Northern Mindanao, Philippines. AACL Bioflux, 8(4), 588–601.
Chahouri, A., Yacoub, B., Abdellatif, M., and Banaoui, A. (2023). Bivalve molluscs as bioindicators of multiple stressors in the marine environment: recent advances. Cont. Shelf Res., 264, 104933. DOI 10.1016/j.csr.2023.105056
De Guzman, C.E., Tampus, A.D., Valdez, S.A.L., Tumang, V.M.C., Moneva, C.S.O., and Canalita, E.E. (2015). Species composition and gut content analysis of fishes in Mandulog River System, Iligan City. Adv. Environ. Biol., 9(19), 23–31.
DeForest, D.K., Brix, K.V., and Adams, W.J. (2007). Assessing metal bioaccumulation in aquatic environments: The inverse relationship between bioaccumulation factors, trophic transfer factors and exposure concentration. Aquat. Toxicol., 84(2), 236–246. https://doi.org/10.1016/j.aquatox.2007.02.022 
Dela Cruz, C., De Vera, N., Lapie, L., Catalma, M., and Bunal, R. (2017). Bioaccumulation and health risks assessment of lead (Pb) in freshwater Asian clams (Corbicula fluminea, Müller) from Laguna de Bay, Philippines. Poll. Res., 36(2), 366–372.
Djikanović, V., Skorić, S., Spasić, S., Naunović, Z., and Lenhardt, M. (2018). Ecological risk assessment for different macrophytes and fish species in reservoirs using biota–sediment accumulation factors as a useful tool. Environ. Pollut., 241, 1167–1174.
Donaher, S., Estes, S., Dunn, R., Gonzales, A., Powell, B., and Martinez, N. (2024). Site- and species-specific metal concentrations, mobility, and bioavailability in sediment, flora, and fauna of a southeastern United States salt marsh. Sci. Total Environ., 922, 171262. https://doi.org/10.1016/j.scitotenv.2024.171262 
EULEX Code 1881–06. (n.d.). EU Commission Regulation (EEC) 1881/2006 maximum level of Pb in food products. (Brussels: European Commission)
Joint FAO/WHO Expert Committee on Food Additives. (2011). Evaluation of certain food additives and contaminants: Seventy-third report of the Joint FAO/WHO Expert Committee on Food Additives (WHO Technical Report Series No. 960). World Health Organization. https://www.who.int/publications/i/item/9789241209601.
Farukuzzaman, M., Sarker, J., Bappy, M., Choudhury, T., Haque, M., Masum, Z., Karim, J., Kabir, H., Arai, T., Ngahe, N., and Hossain, M.B. (2026). Multi-index assessment of heavy metal accumulation and associated ecological-human health risks in fish and sediments adjacent to coal-fired power plant. J. Hazard. Mater. Adv., 21, 101051. https://doi.org/10.1016/j.hazadv.2026.101051 
Gao, Q., Wang, N., Xiang, L., and Sui, Q. (2025). Distribution and pollution assessment of heavy metals in seawater, surface sediments and marine organisms in Lianyungang offshore, China. Reg. Stud. Mar. Sci., 84, 104111. https://doi.org/10.1016/j.rsma.2025.104111 
Gavas, S., Patil, A.J., and Gurav, M. (2026). Global research trends on heavy metal contamination in bivalve. Reg. Stud. Mar. Sci., 96, 104886. https://doi.org/10.1016/j.rsma.2026.104886
Gerhardt, A. (2002). Bioindicator species and their use in biomonitoring. (In UNESCO (Ed.), Encyclopedia of life support systems (Environmental monitoring I). (Oxford, UK: EOLSS Publishers)
Maynard, R. L. (2000). Environmental toxicants: Human exposures and their health effects [Book review]. Occupational and Environmental Medicine, 57(7), 503–504. https://doi.org/10.1136/oem.57.7.503c
Guan, Y., Huang, M., Yang, B., Su, Q., Yu, S., Zhu, Z., Ouyang, X., and Beihai Marine Center. (2026). Occurrence, source identification, and ecological risk assessment of heavy metals in sediments of Beihai Marine Ranching. Reg. Stud. Mar. Sci., 97, 104958. https://doi.org/10.1016/j.rsma.2026.104958
Ho, M. T. G., and Bantoto-Kinamot, V. (2021). Sargassum, Padina and Turbinaria as bioindicators of cadmium in Bais Bay, Negros Oriental. The Palawan Scientist, 13(1), 90–98. https://doi.org/10.69721/TPS.J.2021.13.1.07.
Holt, E. A., and Miller, S. W. (2010). Bioindicators: using organisms to measure environmental impacts. Nat. Educ. Knowl., 3(10), 8.
Islam, M. S., Ahmed, M. K., Habibullah-Al-Mamun, M., and Hoque, M. F. (2018). Heavy metal accumulation in Cerithidea obtusa and associated human health risk in Malaysian mangroves. Mar. Pollut. Bull., 133, 141–148.
Januar, H., Dwiyitno, Hidayah, I., and Hermana, I. (2019). Seasonal heavy metals accumulation in the soft tissue of Anadara granosa mollusc from Tanjung Balai, Indonesia. AIMS Environ. Sci., 6(5), 356–366.
Bureau of Fisheries and Aquatic Resources. (2001). Fisheries Administrative Order No. 210-01: Rules and regulations on the exportation of fresh, chilled and frozen fish and fishery/aquatic products. Department of Agriculture. https://elibrary.judiciary.gov.ph/thebookshelf/showdocs/11/44103
Jolaosho, T.L., Elegbede, I.O., Akintola, S.L., Jimoh, A.A., Ndimele, P.E., Mustapha, A.A., and Adukonu, J.D. (2024). Bioaccumulation dynamics, noncarcinogenic and carcinogenic risks of heavy metals in commercially valuable shellfish and finfish species from the world largest floating slum, Makoko, Nigeria. Mar. Pollut. Bull., 207, 116807. https://doi.org/10.1016/j.marpolbul.2024.116807
Khatri, N., and Tyagi, S. (2015). Influences of natural and anthropogenic factors on surface and groundwater quality in rural and urban areas. Front. Life Sci., 8(1), 23–39.
Lakshmanasenthil, S., Vinothkumar, T., Ajithkumar, T. T., Marudhupandi, T., Veettil, D. K., Ganeshamurthy, R., Ghosh, S., and Balasubramanian, T. (2013). Harmful metal concentrations in sediments and fishes of biologically important estuary, Bay of Bengal. J. Environ. Health Sci. Eng., 11(1), 33.
Lee, C., Idrus, F.A., Aziz, F. (2021). Cadmium and Lead Concentrations in Water, Sediment, Fish and Prawn as Indicators of Ecological and Human Health Risk in Santubong Estuary, Malaysia. Jordan Journal of Biological Sciences., p. 317-325, v. 14. 
McGeer, J.C., Brix, K.V., Skeaff, J.M., DeForest, D.K., Brigham, S.I., Adams, W.J., and Green, A. (2003). Inverse relationship between bioconcentration factor and exposure concentration for metals: Implications for hazard assessment of metals in the aquatic environment. Environ. Toxicol. Chem., 22(5), 1017–1037. https://doi.org/10.1002/etc.5620220509 
Merencillo, R. M., Sevilla‑Nastor, J., Villanueva‑Peyraube, J., and Peyraube, N. (2024). Water quality and risk assessment of selected heavy metals in tilapia (Oreochromis niloticus) from Pulangi Lake, the Philippines. Philipp. J. Sci., 153(2).
Swam, L. M., Rider, M. M., Apeti, D. A., & Pisarski, E. (2023). National Status and Trends, Mussel Watch Program: A 2017 assessment of contaminants of emerging concern in the Gulf of Mexico (NOAA Technical Memorandum NOS NCCOS 323). National Centers for Coastal Ocean Science. https://doi.org/10.25923/d1j6-e075
Niloy, H.K., Chowdhury, A.I., Islam, M.S., Pervez, A., Asseri, A.H., Alsohibany, K.S., Molla, M.H.R., Rahman, M.A., and Uddin, M.S. (2024). Bioaccumulation of heavy metals in water and mollusks in the Karnafully estuary: Potential human health risk and environmental contamination. Reg. Stud. Mar. Sci., 78, 103752. https://doi.org/10.1016/j.rsma.2024.103752
Olivares, R., Sta Maria, E. J., and Sombrito, E. Z. (2019). Environmental assessment of metal pollution in Manila Bay surface sediments. Philipp. J. Sci., 149(S1), 183–195.
Oquiña-Paler, M. K., and Ancog, R. (2014). Copper, lead and zinc concentration in water, sediments and catfish (Clarias macrocephalus, Günther) from Butuanon River, Metro Cebu, Philippines. J. Environ. Sci. Toxicol. Food Technol., 8(11, Ver. II).
Pan, X.D., and Han, J. L. (2023). Heavy metals accumulation in bivalve mollusks collected from coastal areas of southeast China. Mar. Pollut. Bull., 189, 114808. https://doi.org/10.1016/j.marpolbul.2023.114808
Parmar, T. K., Rawtani, D., and Agrawal, Y. K. (2016). Bioindicators: the natural indicator of environmental pollution. Front. Life Sci., 9(2), 110–118.
Perkins, E. (1996). Analytical methods for atomic absorption spectroscopy. (Norwalk, CT: The Perkin-Elmer Corporation)
Raju J, Johnson J, Jeevan A, Capili J (2021) Heavy metal determination of bivalves in Cagayan Valley, Philippines. Scholars Acad J Biosci 9(10): 256–258. DOI: 10.36347/sajb.2021.v09i10.001    
Roa, E. C., Capangpangan, M., and Schultz, M. (2010). Modification and validation of microwave-assisted digestion method for subsequent ICP–MS determination of selected heavy metals in sediment and fish samples in Agusan River, Philippines. J. Environ. Chem. Ecotoxicol., 2(9), 144–151.
Siddique, A.B.; Al Helal, A.S.; Patindol, T.A.; Lumanao, D.M.; Longatang, K.J.G.; Rahman, M.A., Catalvas, L.P.A.; Tulin, A.B.; Shaibur, M.R. (2025). Assessment of Heavy Metal Contamination and Ecological Risk in Urban River Sediments: A Case Study from Leyte, Philippines. Pollutants 2025, 5, 7. https://doi.org/10.3390/pollutants5010007
Singh P., and Gupta S.M. (2021) Mollusks as biomonitors of heavy metal pollution: a review. J Adv Sci Res 12(2 Suppl 1): 35–42.
Skoog, D. A., Holler, F. J., and Crouch, S. R. (2017). Principles of Instrumental Analysis (7th ed.). Cengage Learning.
Supardi W, Puspito‑Nugroho (2019) Bioaccumulation of lead (Pb) in the macroalgae Padina australis Hauck in Makassar marine waters, South Sulawesi, Indonesia. IOP Conf Ser Earth Environ Sci 380: 012021.
Taslima K, Al-Emran M, Rahman MS, Hasan J, Ferdous Z, Rohani MF, Shahjahan M (2022) Impacts of heavy metals on early development, growth and reproduction of fish – A review. Toxicol Rep 9: 858–868.
Tchounwou, P.B., Yedjou, C.G., Patlolla, A.K., and Sutton, D.J. (2012). Heavy metals toxicity and the environment. EXS, 101, 133–164. https://doi.org/10.1007/978-3-7643-8340-4_6 
United States Environmental Protection Agency (USEPA) (1989) Risk Assessment Guidance for Superfund Volume I: Human Health Evaluation Manual (Part A). USEPA, Washington (DC). Report No.: EPA/540/1- 89/002.
U.S. EPA (2001). Methods for Collection, Storage and Manipulation of Sediments for Chemical and Toxicological Analyses: Technical Manual. EPA 823-B-01-002. Washington, DC.
U.S. EPA (2011). The Risk Assessment Information System (RAIS). U.S. Department of Energy’s Oak Ridge Operations Office, Oak Ridge (TN).
U.S. EPA (2003) A review of the reference dose and reference concentration processes. U.S. Environmental Protection Agency, Washington (DC). Report No.: EPA/630/P‑02/002F.
U.S. EPA (2004) Integrated Risk Information System (IRIS). Lead and compounds (inorganic). U.S. Environmental Protection Agency, Washington (DC).
U.S. EPA (1979) Handbook of analytical quality control in water and wastewater laboratories. EMSL-Cincinnati, OH: U.S. Environmental Protection Agency.
U.S. EPA (2011) Exposure Factors Handbook, 2011 Edition (Final Report). U.S. Environmental Protection Agency, Washington (DC). Report No.: EPA/600/R‑09/052F.
Villacarlos, CJ., Villegas, LM, Alburo, R. (2025). Metallothionein induction in bivalves exposed to heavy metals in sediment of the Balamban Coast, Cebu, Philippines. Int. J. Aquat. Biol. (2025) 13(2): 105-117. ISSN: 2322-5270; P-ISSN: 2383-0956
World Health Organization. (2008). Guidelines for drinking-water quality: Third edition incorporating the first and second addenda: Volume 1: Recommendations. World Health Organization. https://www.who.int/publications/i/item/9789241547611.
Yam RSW, Fan YT, Tan Z, Wang TD, Chiu CY (2020). Assessing impacts of metallic contamination along the tidal gradient of a riverine mangrove: multi‑metal bioaccumulation and biomagnification of filter‑feeding bivalves. Forests 11(5): 504.
Yang F, Zhao L, Yan X, Wang Y (2013). Bioaccumulation of trace elements in Ruditapes philippinarum from China: public health risk assessment implications. Int J Environ Res Public Health 10(4): 1392–1405. https://doi.org/10.3390/ijerph10041392
Zhang, W., Huang, L., Wang, W.X. (2012). Biotransformation and detoxification of inorganic arsenic in a marine juvenile fish Terapon jarbua after waterborne and dietborne exposure. Journal of Hazardous Materials 221–222 (2012) 162–169. http://dx.doi.org/10.1016/j.jhazmat.2012.04.027