Since the middle of the last century there has been a growing awareness of the existence of widespread environmental pollution and of the potentially harmful effects that polluting species can have on biological systems. Initially the concern focused on the ubiquity and on the harmful effects of organochlorine compounds, in particular organochlorine pesticides. In the 1970s the malign effect that xeno-estrogenic material could have on biological systems became apparent and the increasing incidence of such polluting material, frequently derived from sewage or other wastewater effluent, in the aquatic environment provoked concern. A more recent topic for research has been the occurrence in the aquatic environment of the residues of pharmaceuticals originally developed and prescribed for the treatment of human or animal illnesses or physiological complaints. Though ample evidence has been recorded for the prevalence of such residues no definite conclusions have been reached regarding the effects of such pollution. This work targeted six compounds that were deemed to have potential for anthropogenic pollution. The species selected were caffeine, methylparaben, estradiol, ethynylestradiol, ibuprofen and nonylphenol. Dublin bay was chosen as a sampling site. HPLC methods for the identification and the quantification of each of these compounds were developed. The method for the detection of caffeine had a limit of detection (LOD) of 0.005 mgL-1 and a limit of quantification (LOQ) of 0.02 mgL-1. The method for estradiol, which utilised the natural fluorescence of this compound as a means of detection, had a LOD of 0.0025 mgL-1 and a LOQ of 0.05 mgL-1. A solid phase extraction method for the extraction of these compounds from seawater was established. This method had a recovery rate of 83.2% for caffeine and 88.9% for estradiol. Items of glassware that would allow the siinultaneous preparation of up to 12 extracts of seawater that would be suitable for HPLC analysis were designed.