Assessing the Impact of Fish Cage Culture on Taal Lake (Philippines) Water and Sediment Quality Using the Zebrafish Embryo Assay


1Department of Biology, College of Arts and Sciences,
University of the Philippines, Manila, Padre Faura, Manila, Philippines
2Department of Ecosystem Analysis, Institute for Environmental Research,
RWTH Aachen University Worringerweg 1 D-52074 Aachen, Germany

*Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.
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percentage survival of Danio rerio embryo

Percentage survival of Danio rerio embryos exposed to Taal Lake waters. Only the positive control was found to be highly different from the water control as indicated by the asterisks (p<0.01). (WC- water control; Gon – Gonzales; Ban – Bañaga; Bal – Balakilong; PC – positive control).




The present study investigated the impact of fish cage aquaculture on the quality of lake water and sediment using a contact assay with zebrafish (Danio rerio) embryos. Fertilized zebrafish embryos were exposed to surface waters and whole sediments collected from three sites of varying levels of stress from Taal Lake, Philippines. Gonzales was the reference site, while Bañaga and Balakilong were sites of heavy aquaculture. No significant developmental differences were observed in water samples collected from all sites. Very high survival rates, high hatching success rates, and few abnormalities were observed in all water samples. All values did not differ significantly from the negative control. Similarly, zebrafish embryos exposed to sediments from the reference site and from sediment control also developed normally and showed no significant defects. However, a significant reduction in both survival and hatching success rates, and a considerable increase in rates of abnormalities, were recorded from sediments obtained from the aquaculture sites. The observed embryotoxic responses were discussed in relation to the presence of contaminants such as ammonia and copper which have settled in the sediments from unconsumed feeds. Results of the study clearly demonstrate that fish cage culture has a harmful impact on lake quality (particularly the sediment phase). We also recommend the use of an effect-directed analysis as a next-level approach to identify specifically other individual toxicants responsible for the teratogenic effects.




Philippine lakes are constantly being threatened with various stressors such as unregulated open fishing, heavy metal pollution, agricultural and domestic pollution and more recently, by fish cage aquaculture (Dela Vega 2001; Yambot 2000; Vista et al. 2006). The reported fish kills in Taal Lake suggest a deteriorating lake quality (Yambot 2000). From May 1998 to June 2001, a total of 38 fish kills in various areas close to aquaculture cages were reported (Rosana & Salisi 2002). Researchers pointed out that the prevailing winds and thermal stratification of the lake’s deep water brought heavy loads of organic sediment to the surface. This resulted in oxygen depletion, and raised levels of ammonia, hydrogen sulfide, and nitrite levels in the lake, contributing to the fish kill. The large organic load in the lake could be traced to excess feed and fish wastes from tilapia cages that have proliferated in the lakes of Agoncillo, Leviste, and Laurel in Batangas City.





AHLF W, HOLLERT H, NEUMANN-HENSEL H, RICKING M. 2002. A guidance for the assessment and evaluation of sediment quality: a German approach based on ecotoxicological and chemical measurements. J Soils & Sediments 2: 37-42.

BACHMANN RW, HOYER MV, CANFIELD DE JR. 2000. The potential for wave disturbance in shallow Florida lakes. Lake Reservoir & Manage 16: 281-291.

[BFAR] Bureau of Fisheries and Aquatic Resources. 2008. Taal Lake Fishery Profile. Available: http://region4a. profiles/taal_lake/taal_lake.htm. Accessed: November 2, 2008.

BRAUNBECK T, BOTTC HER M, HOLLERT H, KOSMEHL T, LAMMER E, LEIST E, RUDOLF M, SEITZ N. 2005. Towards an alternative for the acute fish LC50 test in chemical assessment: the fish embryo toxicity test goes multi-species- an update. Altex 22: 87-102.

BRUNSTRÖM B, BROMAN D, DENCKER L, NAF C, VEJLENS E, ZEBUHR Y. 1992. Extracts from settling particulate matter collected in the Stockholm archipelago waters: embryo lethality, immunotoxicity, and EROD-inducing potency of fractions containing aliphatics/monoaromatics, diaromatic, or polyaromatics. Environ Toxicol Chem 11: 1441-49.

BURTON GA. 1991. Assessing the toxicity of freshwater sediments. Environ Toxicol Chem 10: 1585-27.

CANUSSO M, VIGNATI B, VAN DE GUCHTE C. 2000. Ecotoxicological assessment in the rivers Rhine (The Netherlands) and Po (Italy). Aquat Ecosyst Health Manage 3: 335-345.

DAVE G, XIU R. 1991. Toxicity of mercury, copper, nickel, lead, and cobalt to embryos and larvae of zebrafish, Brachydanio reri. Arch Environ Contam Toxicol 21: 126-134.

DAVIS J. 1987. Analysis of fishkills and associated water quality conditions in the Trinity river, Texas: review of historical data, 1970-1985. Austin, Texas: Texas Water Commission Publ. 107p.

DELA VEGA JT. 2001 Feeds and Feeding Management of Tilapia in Cages. Paper Presented at the 4th Southern Luzon Zonal R and D Review, DAP Tagaytay City, Philippines.

[DENR] Department of Environment and Natural Resources. 1990. Administrative Order No. 34 Series of 1990. Revised water usage and classification/Water quality criteria amending sections No. 68 and 69, Chapter III of the 1978 NPCC rules and regulations. Manila: Department of Environment and Natural Resources. 13p.

EDDY FB, WARD MR, TALBOT C, PRIMMETT D. 1990. Ionic movements across the chorion in newly shed salmon eggs (Salmo salar L.). J Comp Physiol 159: 771-776.

ENSENBACH U, NAGEL R. 1997. Toxicity of binary chemical mixtures: effects on reproduction of zebrafish (Brachydanio rerio). Arch Environ Contam Toxicol 32: 204-210.

FAIRCHILD JF, ALLERT A, SAPPINGTON L, WADELL B. 2005. Chronic toxicity of un-ionized ammonia to early life-stages of endangered Colorado pikeminnow (Ptychocheilus lucius) and razorback sucker (Xyrauchen texanus) compared to the surrogate fathead minnow (Pimephales promelas). Arch Environ Contam Toxicol 49: 378-84.

FELIPO V, KOSENKO E, MINANA MD, MARCAIDA G, GRISOLIA S. 1994. Molecular mechanism of acute ammonia toxicity and of its prevention by l-carnatine. Adv Exp Med Biol 368: 65-77.

FINN R. 2007. The physiology and toxicology of salmonid eggs and larvae in relation to water quality criteria. Aquat Toxicol 81: 337-354.

HAHN ME. 2002. Bioassays and bioassays for detecting dioxin-like compounds in the marine environment. Sci Total Environ 289: 49-69.

HALLARE AV, PAGULAYAN R, LACDAN N, KÖHLER H-R, TRIEBSKORN R. 2005a. Assessing water quality in a tropical lake using biomarkers in zebrafish embryos: developmental toxicity and stress protein responses. Environ Monit & Assess 104: 171-187.

HALLARE AV, KOSMEHL T, SCHULZE T, HOLLERT H, KÖHLER H-R, TRIEBSKORN R. 2005b. Assessing contamination levels of Laguna Lake sediments (Philippines) using a contact assay with zebrafish (Danio rerio) embryos. Sci Total Environ 347: 253-271.

HALLARE AV, NAGEL K, KÖHLER H-R, TRIEBSKORN R. 2006: Comparative embryotoxicity and proteotoxicity of three carrier solvents to zebrafish (Danio rerio) embryos. Ecotox Environ Safety 63: 378-388.

HOLLERT H, DURR M, ERDINGER L, BRAUNBECK T. 2000. Cytotoxicity of settling particulate matter and sediments of the Neckar River (Germany) during a winter flood. Environ Toxicol Chem 19: 528-534.

HOLLERT H, KEITER S, KÖNIG N, RUDOLF M, ULRICH M, BRAUNBECK T. 2003. A new sediment contact assay to assess particle-bound pollutants using zebrafish (Danio rerio) embryos. J Soils Sediments 3: 197-207.

KEITER S, RASTALL A, KOSMEHL T, WÜRM K, ERDINGER L, BRAUNBECK T, HOLLERT H. 2006. Ecotoxicological assessment of sediment, suspended mater and water samples in the upper Danube River. Environ Sci Pollut Res 13: 308-319.

KLUMPP DW, HUMPHREY C, HUASHENG H, TAO F. 2002. Toxic contaminants and their biological effects in coastal waters of Xiamen, China. II. Biomarkers and embryo malformation rates as indicators of pollution stress in fish. Mar Pollut Bull 44: 761-769.

KOSENKO E, KAMINSKI Y, LOPATA O, MURAVYOV N, FELIPO V. 1999. Blocking NMDA receptor prevents the oxidative stress induced by acute ammonia intoxication. Free Radical Biol Med 26: 1369-74.

KRISTENSEN P. 1995. Sensitivity of embryos and larvae in relation to other stages in the life cycle of fish: a literature review. In: Müller R, Lloyd R. (Eds). Sublethal and chronic effects of pollutants in freshwater fish. FAO, Oxford, UK, p. 155-166.

LI WH, CHAN PC, CHAN KM. 2004. Metal uptake in zebrafish embryo-larvae exposed to metal-contaminated sediments. Mar Environ Res 58: 829-832.

LUCKENBACH T, FERLING H, GERNHÖFER M, KÖHLER H, NEGELEB R, PFEFFERLE E, TRIEBSKORN R. 2003. Developmental and subcellular effects of chronic exposure to sub-lethal concentrations of ammonia, PAH and PCP mixtures in brown trout (Salmo trutta f. fario L.) early life stages. Aquat Toxicol 65: 39-54.

MCCORMICK JH, BRODERIUS SJ, FIANDT JT. 1984. Toxicity of ammonia to early life stages of the green sunfish Lepomis cyanellus. Environ Pollut Series. 36: 147-163.

MCDONALD B. 2005. Comparison of pore water and elutriate bivalve larval development toxicity testing in a sediment triad framework. Ecotoxicol Environ Safety 62: 383-390.

MENDIGUCHIA C, MORENO C, MANUEL-VEZ M, GARCIA-VARGAS M. 2006. Preliminary investigation on the enrichment of heavy metals in marine sediments originated from intensive aquaculture effluents. Aquaculture 254: 317-325.

[MEEO] Ministry of Environment and Energy of Ontario.1993. Guidelines for the protection and management of aquatic sediment quality in Ontario. Ontario: Ministry of Environment and Energy of Ontario. 27p.

MONFORT P, KOSENKO E, ERCOG S, CANALES JJ, FELIPO V. 2002. Molecular mechanism of acute ammonia toxicity: role of NMDA receptors. Neurochem Int 41: 95-102.

NAGEL R. 2002. DarT: The embryo test with the zebrafish Danio rerio – a general model in ecotoxicology and toxicology. Altex 19: 38-48.

NAUTA TA, BONGCO AE, SANTOS-BORJA AC. 2003. Set-up of a decision support system to support sustainable development of the Laguna de Bay, Philippines. Mar Pollut Bull 47: 211-218.

NEAL C, ALAN HOUSE W, JARVIE H, NEAL M, HILL L, WICKHAM H. 2006. The water quality of the River Dun and the Kennet and Avon Canal. J Hydrol 330: 155-170.

NEWSOME C, PIRON R. 1982. Aetiology of skeletal deformities in zebra Danio fish. Fish Biol 21: 231-237.

[OSPARCOM] Oslo and Paris Commission. 1994. OSPAR criteria for characterization of sediment quality. Workshop on ecotoxicological assessment criteria for trace metals and organic microcontaminants in the North-East Atlantic (Oslo and Paris Convention). Place of publication: publisher. 39p.

OZOH P. 1980a. Effects of reversible incubations of zebrafish eggs in copper and lead ions with or without shell membranes. Bull Environ Contam Toxicol 24: 270-275.

OZOH P. 1980b. Effects of lead on pigment pattern formation in zebrafish. Bull Environ Contam Toxicol 24: 276-282.

PETERSON RH. 1984. Influence of varying pH and some inorganic cations on the perivitelline potential of eggs of the Atlantic salmon (Salmo salar). Can J Fish Aquat Sci 41: 1066-69.

ROSANA MR, SALISI NC. 2002. Fish Kill Investigation in Taal Lake. Tanauan City, Batangas, Philippines: Inland Fisheries Research Station, Bureau of Fisheries and Aquatic Resources. 18p. 

RUFFER PJ, BOYLE WC, KLEINSCHMIDT J. 1981. Short-term acute bioassays to evaluate ammonia toxicity and effluent standards. J Wastewater Pollut Control Fed 53: 367-377.

SOLBE JF, SHURBEN DG. 1989. Toxicity of ammonia to early life stages of rainbow trout (Salmo gairdneri). Water Res 23: 127-129.

SORMUNEN AJ, LEPANNEN MT, KUKKONEN JVK. 2008; Influence of sediment ingestion and exposure concentrations on the bioavailable fraction of sedimentassociated tetrachlorobiphenyl in oligochates. Environ Toxicol Chem 27: 854-863.

STRMAC M, OBEREMM A, BRAUNBECK T. 2002. Assessment of sediment toxicity to early life stages of fish: effects of sediments from differently polluted small rivers on zebrafish (Danio rerio) embryos and larvae. J Fish Biol 61: 24-38.

[USEPA] United States Environmental Protection Agency. 1992. Revised tables for determining average freshwater ammonia concentrations. Place of publication: publisher. Total number of pages.

TRIEBSKORN R, KÖHLER H-R, HONNEN W, SCHRAMM M, ADAMS SM, MÜLLER E. 1997. Induction of heat shock proteins, changes in liver ultrastructure, and alterations of fish behavior: Are these biomarkers related and are they useful to reflect the state of pollution in the field? Aquat Ecosyst Stress Recov 6: 57-73.

VISTA A, NORRIS P, LUPI F, BERNSTEN R. 2006. Nutrient loading and efficiency of tilapia cage culture in Taal Lake, Philippines. Philipp Agric Sci 89: 48-57.

WEIS JS, WEIS P. 1987. Pollutants as Developmental Toxicants in Aquatic Organisms. Environ Health Perspect 71: 77-85.

YAMBOT A.V. 2000. Problems and issues of Nile tilapia cage farming in Taal Lake, Philippines. In: Liao IC and Lin CK (eds.) Proceedings of the First International Symposium on Cage Aquaculture in Asia. Asian Fisheries Society, Manila and World Aquaculture Society - Southeast Asian Chapter, Bangkok. p. 241-252.