ORGANOCHLORINE RESIDUES IN TISSUES OF STRIPED DOLPHINS AFFECTED BY THE 1990 MEDITERRANEAN EPIZOOTIC - RELATIONSHIPS WITH THE FATTY-ACID COMPOSITION

A simple and rapid method was developed for the simultaneous determina tion of fatty acids, organochlorine pesticides, and polychlorinated bi phenyl (PCB) congeners in the same sample in order to explore possible connections between levels of contaminants and fatty acid composition . The method was applied to samples of melon, cerebrum, cerebellum, lu ng, liver, kidneys, and skeletal muscle obtained from 5 male and 5 fem ale striped dolphins (Stenella coeruleoalba) found stranded in 1990 in the northeastern Spanish coasts during the morbillivirus epizootic th at affected this cetacean in the Mediterranean Sea. The results indica te that PCBs were dominant in all tissues, with the highest geometric mean concentration being found in melon (903 mu g g(-1) wet wt); Sigma DDTs were also found at high concentrations (111 mu g g(-1) wet wt, i n melon). Statistical analysis indicate that organochlorine concentrat ion was correlated with the fatty acid composition of tissues, althoug h some of these variations can be interpreted as a consequence of a sh ift in the diet produced in the striped dolphin population. However, o ther changes such as the negative correlation with arachidonic acid ma y suggest that the eicosanoid production could have been affected by t he extremely high concentrations of PCBs and Sigma DDTs.