Systematic Collaborative Studies on Neoplasms in Marine Animals as Related to the Environment*

Prospective study of infectious and noninfectious diseases in oysters and fishes in three Gulf of Mexico estuaries

“…Considerable data were published from which inferences have been made that fishes and shellfishes inhabiting contaminated waters are at higher disease risks than those in cleaner environments. Most of these studies from which data derived were retrospective epizootiological efforts initiated after the fact, because certain fish diseases were increasingly observed or because fish kills were noted or had recurred frequently in specific bodies of water (Cooper & Keller 1969, Perkins et al 1972, Couch & Nimmo 1974, Mearns & Sherwood 1977, Stich et al 1977, Hard et al 1979, Kimura et al 1984. Because of the retrospective nature of these studies the conclusions drawn from them were mainly confirma-O Inter-Research/Printed in F. R. Germany tory of conditions known or suspected, or the basis for rejection of previously held hypotheses.…”

Three Types of Skin Papillomas of Flatfishes and Their Causes

“…Only in the Bering Sea do the distribution ranges of this disease and Type 3 complex papilloma overlap. In these waters the rock sole Lepidopsetta bilineata is afflicted with the complex type of papilloma, and the yellow-fin sole Limanda aspera by lymphocystis disease (Stich et al, 1977;Wellings et al, 1977).…”

“…In the immediate region of the city, especially at the mouth of the Frazer River, and in the bays to the south, the maximum rate of occurrence in young fishes living near the shore ranges from 45 to almost 60 O/O (Stich et al, 1977). The lowlands of the Frazer River mouth are heavily industrialized; they are also the site of the central sewage processing plant for the city.…”

“…Percentage of indimduals wlth skin papillomas in populations of young English sole Parophrys vetulus in coastal areas near Vancouver, Canada (After Stich, 1977) A comparative study of tumour occurrence along the Pacific Caost of North America from San Francisco north to Queen Charlotte Island strengthened the impression that the distribution of this disease is correlated with the concentrations of settlements and industrial aggregations, such as San Francisco, Eureka, Grays Harbour and most notably Seattle and Vancouver. There are a few facts that seem to speak against this interpretation, however. For example, while both flatfish species, Parophrys vetulus and Platichthys stellatus, are highly afflicted (33 O/O and 55 '/o respectively) in the Bay of Bellingham about 50 km south of Vancouver, at the mouth of the Frazer River P. stellatus is only afflicted at a rate of 0.2 "/a, but P. vetulus at a rate of almost 60 O/O (Stich et al, 1977). Furthermore, the sand sole (Psettichthys melanostictus) is afflicted at a rate of about 30 O/O in the northern coastal waters off Queen Charlotte Island, which are almost free of waste contamination, while P. vetulus is not affected at all in these waters.…”

Skin tumours in Pleuronectes obscurus (Pleuronectidae) represent a complex combination of epidermal papilloma and rhabdomyosarcoma

“…In some large rounded cells, large vacuoles English sole from the coastal areas near Vancouver, were present in the cytoplasm. Some of these cells were Canada (Stich et al 1977), rock sole Lepidopsetta bilidegenerating. Large rounded cells replaced the epiderneata from the Bering Sea (McCain et al 1978(McCain et al , 1979.…”