Organochlorines are ubiquitous pollutants of the marine environment. These lipid-soluble and highly persistent compounds are found in detectable amounts in almost all marine organisms, and accumulate in the lipid tissues of marine animals. This bioaccumulation leads to biomagnification of these contaminants in higher trophic levels. Near the top of many marine food chains are found the marine mammals, in whose blubber high levels of organochlorine residues have been measured. The most commonly occurring of these pollutants in these animals are the polychlorinated biphenyls (PCB's) and p,p-DDE, a metabolite of the insecticide DDT. These substances have been shown to cause disruptions in the endocrine, immune, and reproductive systems, and are passed from mother to offspring through the placenta and by lactation. Presence and levels of residues of these compounds are, therefore, monitored in marine mammals to provide an indication of the health of a given population and the environment in which they live. Such monitoring is generally done with the use of gas chromatography (GC). High performance liquid chromatography (HPLC) is little used due to the poor ultraviolet (UV) absorbance properties of many of the organochlorines. PCB's and p,p-DDE do absorb UV well enough at concentrations usually encountered in marine mammals to permit the use of HPLC for detection and semiquantification of these substances. A method was developed for the screening of blubber of marine mammals for total PCB's and p,p-DDE using HPLC. The method was applied to the detection and approximation of levels of these two organochlorines in marine mammals from the east and west coasts of the United States. Geographical differences in levels of the two pollutants were found, indicating differences in primary feeding ranges. Evidence of placental transfer of these two organochlorines was also found. Especially high residue levels were found in the blubber of stranded killer whales, indicating that acquisition of high pollutant burdens is still a problem in these top predators. It was concluded that HPLC can be used to screen marine mammals for PCB's and p,p-DDE, and that residue levels determined can be useful in investigating species range, pollutant burdens, and health of populations.
| Identifer | oai:union.ndltd.org:pdx.edu/oai:pdxscholar.library.pdx.edu:open_access_etds-2394 |
| Date | 01 January 1996 |
| Creators | Hayteas, David Lawrence |
| Publisher | PDXScholar |
| Source Sets | Portland State University |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | Dissertations and Theses |
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