Ecological Risk Assessment of Heavy Metal Pollution in Surface Water and Sediment of Lahug River, Cebu, Philippines
Main Article Content
Abstract
The Lahug River, a significant urban waterway in Metro Cebu, was studied to assess its water quality and sediment characteristics. Physicochemical properties, such as pH and dissolved oxygen (DO), were measured in situ using a Multi-probe digital meter. At the same time, metal concentrations in both water and sediments were determined through Flame Atomic Absorption Spectroscopy (FAAS) with multiple standard addition techniques. In water, metal concentration showed a decreasing trend of Zn > Pb > Cu > Cr. Notably, copper (Cu) and chromium (Cr) exceeded the National Environmental Protection Agency (NEPA, 1989) threshold at the downstream station, while all stations exceeded the limit for zinc (Zn). In sediments, copper emerged as the most prevalent metal. Statistical analysis indicated significant correlations among Cu, Zn, Pb, and Cr, suggesting similar pollution sources or behaviors in the river environment. Ecological risk assessment revealed that the downstream area exhibited the highest risk, highlighting the urgency of rehabilitative measures to protect the river ecosystem. A comprehensive, large-scale environmental risk assessment is recommended to mitigate further degradation and ensure sustainable management of the Lahug River
Article Details

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
References
Srebotnjak, T.; Carr, G.; de Sherbinin, A.; Rickwood C. A global Water Quality Index and hot-deck imputation of missing data. Ecol. Indic. 2012. 17, 108–119. https://doi.org/10.1016/j.ecolind.2011.04.023
Su, S.; Xiao, R.; Mi, X.; Xu, X.; Zhang, Z; Wu, J. Spatial determinants of hazardous chemicals in surface water of Qiantang River, China. Ecol. Indic. 2013. 24, 375-381. https://doi.org/10.1016/j.ecolind.2012.07.01510.2965/jwet.2014.109
Aziz, K. H. H.; Mustafaa, F. S.; Omer, K. M.; Hamaa, S.; Hamarawfa, R. F.; Rahman, K. O. Heavy metal pollution in the aquatic environment: Efficient and low-cost removal approaches to eliminate their toxicity: A review. RSC Adv. 2023, 13(33), 17595-17610. https://doi.org/10.1039/D3RA01317A
Rizabal, T.A.C.; Villegas, L.M.G.; Alburo, H.M.A.; Velasco, L.M.; Alburo, R.P. Lead content in Moringa oleifera Linn. leaves and rootzone soil in the nine cities of Cebu province, Philippines. Philipp J Sci. 2023. 153(1), 133-145. https://doi.org/10.56899/153.01.14
Rohde, S.; Hostmann, M.; Peter, A.; Ewald, K.C. Room for rivers: An integrative search strategy for floodplain restoration. Landsc. Urban Plan. 2006. 78, 50-70. https://doi.org/10.1016/j.landurbplan.2005.05.006
Richardson, M.; Soloviev, M. The urban river syndrome: achieving sustainability against a backdrop of accelerating change. Int. J Environ. Res. Public Health. 2021, 18(12), 6406. https://doi.org/10.3390/ijerph18126406
Yi, Y.; Yang, Z.; Zhang, S. Ecological risk assessment of heavy metals in sediment and human health risk assessment of heavy metals in fishes in the middle and lower reaches of the Yangtze river basin. Environ. Pollut. 2011, 159, 2575-2585. https://doi.org/10.1016/j.envpol.2011.06.011
Bensig E.; Flores M. J.; Maglangit F. Assessment of the water quality in Buhisan, Bulacao and Lahug rivers, Cebu, Philippines using fecal and total coliform as indicators. Curr. World Environ. 2014, 9(3), https://doi.org/10.12944/CWE.9.3.03
Maglangit, F.; Galapate, R.; Bensig, E. Physico-chemical assessment of the water quality of Buhisan river, Cebu, Philippines. Int. J. Res. Environ. Sci. Technol. 2014, 4, 83-87.
Khadse, G.K.; Patni, P.; Kelkar, P.S.; Devotta, S. Qualitative evaluation of Kanhan river and its tributaries flowing over central Indian plateau. Environ. Monit. Assess. 2008, 147, 83-92. https://doi.org/10.1007/s10661-007-0100-x
Venugopal, T.; Giridharan, L.; Jayaprakash, M.; Velmurugan, P.M. A comprehensive geochemical evaluation of the water quality of River Adyar India. Bull. Environ. Contam. Toxicol. 2009. 82, 211-217. https://doi.org/10.1007/s00128-008-9533-3
Yang, H.J.; Jeong, H.J.; Bong, K.M.; Jin, D.R.; Kang, T.W.; Ryu, H.S.; Han, J.H.; Yang, W.J.; Jung, J.; Hwang, S.H.; Na, E.H. Organic matter and heavy metal in river sediments of southwestern coastal Korea: spatial distributions, pollution, and ecological risk assessment. Mar. Pollut. Bull. 2020, 59, https://doi.org/10.1016/j.marpolbul.2020.111466
Jaiswal, R.; Malik, A. Metal resistance in Pseudomonas strain isolated from soil treatment with industrial wastewater. World J. Microbiol. Biotechnol. 2000, 16, 177-182. https://doi.org/10.1023/A:1008905902282
Gavrilescu, M. Removal of heavy metal from the environment by biosorption. Eng. Life Sci. 2004, 4(3), 219-232. https://doi.org /10.1002/elsc.200420026
Geolin, K.R.C.; Villegas, L.M.G.; Alburo, R.P. Metallothionein response of aninikad, Canarium labiatum (Roding, 1798) to heavy metal concentrations in Balamban coastline, Cebu. J. Agri. Technol. Manag. 2021, 24(1), 1-12.
Cervantes, C.; Corona, F.G. Copper resistance mechanisms in bacteria and fungi. FEMS Microbiol. Rev. 1994, 14, 121-138. https://doi.org/10.1111/j.1574-6976.1994.tb00083.x
Nies, D.H. Microbial heavy-metal resistance. Appl. Microbiol. Biotechnol. 1999, 51, 730-750. https://doi.org/10.1007/s002530051457
Choudhury, R.; Srivastava, S. Mechanism of zinc resistance in Pseudomonas putida strain S4. World J. Microbiol. Biotechnol. 2001. 17, 149-153. https://doi.org/10.1023/A:1016666000384
Gupta, R.; Ahuja, P.; Khan, S.; Saxena, R.K.; Mohapatra, H. Microbial biosorbents: meeting challenges of heavy metal pollution in aqueous solutions. Curr. Sci. 2000, 78(8), 967–973.
Aleem, A.; Isar, J.; Malik, A. Impact of long-term application of industrial waste water on the emergence of resistance traits in Azotobacter chroococcum isolated from rhizospheric soil. Bioresour. Technol. 2003, 86(1), 7-13. https://doi.org/10.1016/S0960-8524(02)00134-7
U.S. EPA. Methods for Collection, Storage and Manipulation of Sediments for Chemical and Toxicological Analyses: Technical Manual. Office of Water, U.S. Environmental Protection Agency, Washington, DC. 2001, 208pp.
Suresh, G.; Sutharsan, P.; Ramasamy, V.; Venkatachalapathy, R. Assessment of spatial distribution and potential ecological risk of the heavy metals in relation to granulometric contents of Veeranam lake sediments, India. Ecotoxicol. Environ. Saf. 2012, 84, 117-124. https://doi.org/10.1016/j.ecoenv.2012.06.027
Gao X.; Zhuang W.; Chem C.A.; Zhang Y. Sediment quality of the SW Coastal Laizhou Bay, Bohai Sea, China: A comprehensive assessment based on the analysis of heavy metals. PLoS One. 2015, 10, 3. https://doi.org/10.1371/journal.pone.0122190
Islam, M.S.; Ahmed, M.K.; Raknuzzaman, M.; Habibullah-Al-Mamun, M.; Islam, M.K. Heavy metal pollution in surface water and sediment: a preliminary assessment of an urban river in a developing country. Ecol. Indic. 2015, 48, 282-291. https://doi.org/10.1016/j.ecolind.2014.08.016
National Environmental Protection Agency. Water quality standard for metal. Beijing: GB. 1989. 11607-89.
Haque, S. E. Urban water pollution by heavy metals, microplastics, and organic contaminants. Current directions in water scarcity research. 2022, 6, 21-43. https://doi.org/10.1016/B978-0-323-91838-1.00001-4
Alburo, R. P.; Gabrillo, S. L.; Villegas, L. M. G. Characteristic Metal Marker of Non-exhaust PM 10 Vehicular Emissions in Cebu City, Philippines. Philipp. J. Sci. 2023, 152(4), https://doi.org/10.56899/152.04.06
Luo, Z.; Shao, Q.; Liu, H. Comparative evaluation of river water quality and ecological changes at upstream and downstream sites of dams/sluices in different regulation scenarios. J. Hydrol. 2021, 597, https://doi.org/10.1016/j.jhydrol.2021.126290
Martin, J.M.; Meybeck, M. Elemental mass balance of materials carried by major world rivers. Mar. Chem. 1979, 7, 173-206. https://doi.org/10.1016/0304-4203(79)90039-2
Bai, J.; Cui, B.; Chen, B.; Zhang, K.; Deng, W.; Gao, H.; Xiao, R. Spatial distribution and ecological risk assessment of heavy metals in surface sediments from typical plateau lake wetland. China Ecol. Modell. 2011, 222, 301-306. https://doi.org/10.1016/j.ecolmodel.2009.12.002
Mohiuddin, K. M.; Zakir, H. M.; Otomo, K.; Sharmin, S.; Shikazono, N. Geochemical distribution of trace metal pollutants in water and sediments of downstream of an urban river. Int. J. Environ. Sci. Tech. 2010, 7(1), 17-28. https://doi.org/10.1007/BF03326113
Harikumar, P.S.; Nasir, U.P. Ecotoxicological impact assessment of heavy metals in core sediments of a tropical estuary. Ecotoxicol. Environ. Saf. 2010, 73, 1742-1747. https://doi.org/10.1016/j.ecoenv.2010.08.022
Marín, J.; Colina, M.; Ledo, H.; Gardiner, P.H.E. Ecological risk by potentially toxic elements in surface sediments of the Lake Maracaibo (Venezuela). Environ. Eng. Res. 2022, 27(4), https://doi.org/10.4491/eer.2021.232
Allard, P.; Fairbrother, A.; Hope, B.K.; Hull, R.N.; Johnson, M.S.; Kapustka, L.; Mann, G.; McDonald, B.; Sample, B.E. Recommendations for the development and application of wildlife toxicity reference values. Integr. Environ. Assess. Manag. 2010, 6, 28-37. https://doi.org/10.1897/IEAM_2009-010.1
Suresh, G.; Ramasamy, V.; Meenakshisundaram, V.; Venkatachalapathy, R.; Ponnu- samy, V. Influence of mineralogical and heavy metal composition on natural radionuclide contents in the river sediments. Appl. Radiat. Isot. 2011, 69, 1466-1474. https://doi.org/10.1016/j.apradiso.2011.05.020
Oquiñena-Paler, M.K.M., Ancog, R. Copper, lead and zinc concentration in water, sediments and catfish (Clarias macrocephalus gunther) from Butuanon River, Metro Cebu, Philippines. IOSR J Environ Sci Toxicol Food Tech. 2014, 8, 49-56. https://doi.org/10.9790/2402-081124956
Cañete, R.C.; Villegas, L.M.G.; Castañares, J.M. Seasonal bioaccumulation of copper in guppy, Poecilia reticulata (Peters) with characterization of the hydrophobic fraction of its octanol-water emulsion. KIMIKA. 2014, 25(1), 27-37. https://doi.org/10.26534/kimika.v25i1.27-37
Villacarlos, C. J. A.; Villegas, L. M. G.; Alburo, R. P. Metallothionein induction in bivalves exposed to heavy metals in sediment of the Balamban Coast, Cebu, Philippines. Int. J. Aquat. Biol. 2025, 14(2), https://doi.org/10.22034/ijab.v13i2.2425
Hakanson, L. An Ecological Risk Index for Aquatic Pollution Control: A Sedimentological Approach, Water Res. 1980, 14, 975-1001. https://doi.org/10.1016/0043-1354(80)90143-8