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marine pollution:

NUTRIENT POLLUTION . Nutrients are essential for life in the oceans BUT . there is growing concern over the accelerated nutrient ENRICHMENT of coastal waters as a result of human activities . NUTRIENT SOURCES. Nutrient sources in the marine environment can be broadly classified as: Point sources or Diffuse sources.

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marine pollution:

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    30. Table 12.1

    37. “Don’t go in the water” U.S. News & World Report, Aug. 16, 2004. Notes the growing problems of sewage discharge affecting US beaches, 2003 - 18,000 unhealthy days reported 50% increase from 2002

    38. Several studies have suggested that marine mammals may be susceptible to infection via human or livestock pathogens transferred via domestic or agricultural sewage effluents. a hepatitis outbreak in the US was believed to be the result of a virus transferred to marine mammals by human sewage. [Britt et al., (1979)] bacteria associated with sewage water contaminated with human pathogens, have been documented in marine mammals, such as Escherichia coli, Mycobacterium tuberculosis, Vibrio cholera and Salmonella sp. [Grillo et al. (2001)]. Sewage-borne fungi could also infect marine mammals e.g. Candida sp. (common component in sewage wastes) and has been isolated from cetaceans. [Sweeny et al. (1976); Dunn et al. (1982)]

    39. In order for a pathogen to infect a cetacean, a site of entry is required. These include: [Grillo et al. (2001)] (a) mucous membranes; (b) the respiratory tract; (c) lesions and lacerations cetaceans frequently receive cuts and wounds from marine litter or nets, or from other cetaceans; these wounds are often the site of entry for bacterial diseases [Fujioka et al. (1988)] (d) the gastrointestinal tract - from ingested water and consuming prey contaminated by pathogens as the result of living in polluted waters [Smith and Boyt (1990)]

    40. An estimation of sewage pathogen exposure predicted that porpoises and dolphins in Scotland - even when the researchers assumed that that cetaceans were in waters which were clean enough to potentially be classified as bathing waters- could be exposed to substantial quantities of bacteria through ingesting seawater alone. [Grillo et al. (2001)] i.e. daily ingestion: up to 2,000-10,000 faecal coliforms day-1 for harbour porpoises or 6,000-30,000 faecal coliforms day-1 for bottlenose dolphins [Grillo et al., (2001)].

    41. Every day these animals would be exposed to pathogen levels that are several orders of magnitude higher than would be considered unsafe for humans - in a “one-off” exposure. Coastal waters are likely to be far more contaminated than the bathing beach waters used in the above exposure estimation. Cetaceans living in in waters near urban areas, or sewage contaminated areas, would be expected to have very high pathogen intakes

    42. NB – animals exposed to sewage borne pathogens may also be suffering from of immune suppression caused by anthropogenic chemicals (organohalogens/trace elements /TBT) Many pathogens contained in sewage are opportunistic and it an animals is stressed, injured or particularly if its immune system is compromised, infection could occur - even if in normal circumstances animals might have been able to resist the infection. e.g. cetaceans in the UK, where disease is the cause of death, have been found to possess significantly higher concentrations of organohalogen or trace element contaminants [Bennett et al. (2001); Jepson et al., (1999); Jepson et al., (2005)]

    43. REFERENCES Bennett, P.M., Jepson, P.D., Law, R.J., Jones, B.R., Kuiken, T., Baker, J.R., Rogan, E. and Kirkwood, J.K.  2001.  Exposure to heavy metals and infectious disease mortality in harbour porpoises from England and Wales. Environmental Pollution 112: Brodie, D.A. and Hanson, H.M. 1960. A study of the factors involved in the production of gastric ulcers by the restraint technique. Gastroenterology 38: 353-360. Costas, E. and Lopez-Rodas, V. 1998. Paralytic phycotoxins in monk seal mass mortality. Veterinary Record 142: 643-644. Dunn, J.L., Buck, J.D. and Spotte, S. 1982. Candidiasis in captive cetaceans. Journal of the American Veterinary Medical Association 185: 1328-1330. Flewelling, L.J., Naar, J.P., Abbott, J.P., Baden, D.G., Barros, N.B., Bossart, G.D., Bottein, M.-Y.D., Hammond, D.G., Haubold, D.G., Heil, C.A., Henry, M.S., Jacocks, H.M., Leighfield, T.A., Pierce, R.H., Pitchford, T.D., Rommel, S.A., Scott, P.S., Steidinger, K.A., Truby, E.W., Van Dolah, F.M. and Landsberg, J.H. 2005. Red tides and marine mammal mortalities. Nature 435: 755-756. Fujioka, R.S., Greco, S.B., Cates, M.B. and Schroeder, J.P. 1988. Vibrio damsela from wounds in bottlenose dolphins Tursiops truncatus. Diseases of Aquatic Organisms 4: 1-8. Geraci, J.R., Anderson, D.M., Timperi, R.J., St. Aubin, D.J., Early, G., Prescott, J.H. and Mayo, C.A. 1989. Humpback whales (Megaptera novaeangliae) fatally poisoned by dinoflagellate toxin. Canadian Journal of Fisheries and Aquatic Sciences 46: 1895-1898.Grillo et al. 2001 Hernandez, M., Robinson, I., Aguilar, A., Gonzalez, L.M., Lopez-Jurado, L.F., Reyero, M.I., Cacho, E., Franco, J., Lopez-Rodas, V. and Costas, E. 1998. Did algal toxins cause monk seal mortality. Nature 393: 28-29. Jepson, P.D., Bennett, P.M., Allchin, C.R., Law, R.J., Kuiken, T., Baker, J.R., Rogan, E. and Kirkwood, J.K. 1999. Investigating potential associations between chronic exposure to polychlorinated biphenyls and infectious disease mortality in harbour porpoises from England and Wales. The Science of the Total Environment 243/244: 339-348. Jepson, P.D., Bennett, P.M., Deaville, R., Allchin, C.R., Baker J.R. and Law, R.J.  2005. Relationships between PCBs and health status in UK-stranded harbour porpoises (Phocoena phocoena). Environmental Toxicology and Chemistry 24: 238–248. Kuiken, T., Simpson, V.R., Allchin C.R., Bennett, M., Codd, G.A., Harris, E.A., Howes, G.J., Kennedy, S., Kirkwood, J.K., Law, R.J., Merrett, N.R. and Phillips, S. 1994. Mass mortality of common dolphins (Delphinus delphis) in south-west England due to incidental capture in fishing gear. Veterinary Record 134: 81-89.

    44. REFERENCES Legrand, A.M. 1998. Ciguatera toxins: origin, transfer through food chain and toxicity to humans. In: Harmful Algae (Ed. by B. Reguera, J. Blanco, M.L. Fernandez, T. Wyatt T), pp. 39-43. Xunta de Galacia and IIntergovernmental Oceanographic Commission, Santiago del Compostella. Smith, A.W. and Boyt, P.M. 1990. Calciviruses of ocean origin: a review. Journal of Zoo and Wildlife Medicine 21: 3-23. Sweeny, J.C., Migaki, G. and Vanik, P.M. 1976. Systemic mycoses in marine mammals. Journal of the American Veterinary Medical Association 169: 946-948. Van Dolah, F.M. 2000. Marine algal toxins: origins, health effects, and their increased occurrence. Environmental Health Perspectives 108 (Suppl. 1): 133-141. Van Dolah, F.M., Doucette, G.J., Gulland, F.M.D., Rawles, T.L. and Bossart, G.D. 2003. Impacts of algal toxins on marine mammals. In: Toxicology of marine mammals (Ed. by J.G. Vos, G.D. Bossart, M. Fournier and T.J. O’Shea), pp. 247-269. Taylor and Francis, London. Clark R.B.. 2003. Oxygen demanding wastes. In: Marine Pollution, 5th Edition, pp. 35-63. Oxford University Press, Oxford.

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