Acute toxicity of 353-nonylphenol and its metabolites for zebrafish embryos
- 2k Downloads
Background, aim and scope
Nonylphenol (NP) can be detected in the aquatic environment all over the world. It is applied as a technical mixture of isomers of which 353-NP is the most relevant both in terms of abundance (about 20% of total mass) and endocrine potential. 353-NP is metabolised in sewage sludge. The aims of the present study were to determine and to compare the acute toxicity of t-NP, 353-NP and its metabolites as well as to discuss if the toxicity of 353-NP changes during degradation.
Materials and methods
353-NP and two of its metabolites were synthesised. The zebrafish embryo test was performed according to standard protocols. Several lethal and non-lethal endpoints during embryonal development were reported. NOEL, LOEL and EC50 were calculated.
All tested compounds caused lethal as well as non-lethal malformations during embryo development. 353-NP showed a higher toxicity (EC50 for lethal endpoints 6.7 mg/L) compared to its metabolites 4-(3.5-dimethyl-3-heptyl)-2-nitrophenol (EC50 13.3 mg/L) and 4-(3,5-dimethyl-3-heptyl)-2-bromophenol (EC50 27.1 mg/L).
In surface water, concentrations of NP are far below the NOEC identified by the zebrafish embryo test. However, in soils and sewage sludge, concentrations may reach or even exceed these concentrations. Therefore, sludge-treated sites close to surface waters should be analysed for NP and its metabolites in order to detect an unduly high contamination due to runoff events.
The results of the present study point out that the toxicity of 353-NP probably declines during metabolisation in water, sediment and soil, but does not vanish since the major metabolites exhibit a clear toxic potential for zebrafish embryos.
Recommendations and perspectives
Metabolites of environmental pollutants should be included in the ecotoxicological test strategy for a proper risk assessment.
KeywordsDanio rerio Degradation Metabolites Nonylphenol Toxicity
- Amacher SL, Draper BW, Summers BR, Kimmel CB (2002) The zebrafish T-box genes no tail and spadetail are required for development of trunk and tail mesoderm and medial floor plate. Development 129:3311–1123Google Scholar
- Braunbeck T, Böttcher 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-Altern Tierexp 22:87–102Google Scholar
- DIN (2001) DIN 38 415-T6, German standard methods for the examination of water, waste water and sludge—Subanimal testing (group T)—Part 6: Determination of the non-acute-poisonous effect of waste water to fish eggs by dilution limits. German Standardisation Organisation, Beuth Vertrieb GmbH, BerlinGoogle Scholar
- ISO (2007) ISO 15088:2007 Water quality—determination of the acute toxicity of waste water to zebrafish eggs (Danio rerio)Google Scholar
- Kammann U, Biselli S, Reineke N, Wosniok W, Danischewski D, Hühnerfuss H, Kinder A, Sierts-Herrmann A, Theobald N, Vahl HH, Vobach M, Westendorf J, Steinhart H (2005) Bioassay-directed fractionation of organic extracts of marine surface sediments from the North and Baltic Sea—Part II: Results of the biotest battery and development of a biotest index. J Soil Sediment 5(4):225–232CrossRefGoogle Scholar
- Lee H, Peart TE, Chan J, Gris G (2004) Occurrence of endocrine-disrupting chemicals in sewage and sludge samples in Toronto, Canada. Water Qual Res J Can 39:57–63Google Scholar
- Nagel R (2002) DarT: the embryo test with the zebrafish Danio rerio—a general model in ecotoxicology and toxicology. Altex-Altern Tierexp 19(Suppl 1):38–48Google Scholar
- OECD (2006) Organisation for Economic Co-operation and development, Environment Directorate (OECD)—Current approaches in the statistical analysis of ecotoxicity data: a guidance to application. OECD Series on Testing and Assessment, Number 54, Paris 2006Google Scholar
- Petrovic M, Diaz A, Ventura F, Barcelo D (2001) Simultaneous determination of halogenated derivatives of alkylphenol ethoxylates and their metabolites in sludges, river sediments, and surface, drinking, and wastewaters by liquid chromatography–mass spectrometry. Anal Chem 73(24):5886–5895CrossRefGoogle Scholar
- SAS Institute Inc. (2004) SAS OnlineDoc® 9.1.3. Cary: SAS Institute Inc.Google Scholar