Paul C. Baumann

Effects of high tissue concentrations of selenium on reproduction by bluegills

Abstract Recent studies have associated high body concentrations of selenium with declines in fish populations inhabiting cooling reservoirs of coal-fired electric power plants. Because some evidence indicated that these declines resulted from reduced reproduction, we made a series of 18 artificial crosses of bluegills Lepomis macrochirus possessing high and low body concentrations of Se to determine whether elevated Se in parents reduced viability of gametes or increased mortality of embryos and larvae. Bluegills with high body concentrations of Se were obtained from Hyco Reservoir (cooling water source of a coal-fired power plant) and those with low body concentrations were obtained from nearby Roxboro City Lake, North Carolina. Neither percent fertilization nor percent hatch of eggs differed significantly among the parent combinations. However, all crosses (8) that included females with high Se body concentrations resulted in larvae with edema; such larvae did not survive to the swim-up stage. Only one...

The status of selected organics in the Laurentian Great Lakes: an overview of DDT, PCBs, dioxins, furans, and aromatic hydrocarbons

Abstract Dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyls (PCBs) have declined in biota of the Laurentian Great Lakes from the late 1970s through the early 1980s. Concentrations of these compounds in lake trout (Salvelinus namaycush) from Lakes Superior, Huron, Michigan, and Ontario, and walleye (Stizostedion vitreum) from Lake Erie have fluctuated at new lower levels since the early 1980s. In 1984–1985 fish from Lake Ontario had the highest concentrations and fish from Lakes Superior and Erie the lowest concentrations of both total DDT and total PCBs. Chlorinated dibenzofurans (PCDFs) and dibenzo-p-dioxins (PCDDs) occur in fish from all the Great Lakes and are highest in fish from Saginaw Bay in Lake Huron. Reproductive failure in a Forsters tern (Sterna forsteri) colony from Green Bay, Lake Michigan has been associated with concentrations of dioxin-like compounds in the eggs. Polynuclear aromatic hydrocarbons (PAHs) as represented by fluoranthene and the carcinogen, benzo(a)pyrene, are most concentrated near industrialized areas of the Great Lakes, particularly in association with coking facilities. High concentrations of these compounds have been found in the tissue or stomach contents of fish populations having high frequencies of tumors.

Tumor Frequencies and Contaminant Concentrations in Brown Bullheads from an Industrialized River and a Recreational Lake

Abstract Frequencies of external and grossly visible liver tumors were high in brown bullheads Ictalurus nebulosus from Black River, an industrialized Lake Erie tributary. Skin and liver tumors were lacking in brown bullheads from Buckeye Lake, a reference site, and the incidence of lip tumors was low (<2%). Liver tumors, primarily cholangiocarcinomas, increased significantly (P < 0.05) with age in Black River brown bullheads, occurring in 28–44% of the 4-year-old fish collected in 1980–1982. External tumors did not increase consistently with age. Within year classes, the occurrence of grossly observable liver tumors was higher in fall than in spring. Liver tumor incidence was not correlated with sex. Organic contaminants were higher in brown bullheads from the Black River than in those from Buckeye Lake. Polynuclear aromatic hydrocarbons were particularly high, including carcinogens such as benz[a]anthracene and benzo[a]pyrene (B[a]P). Limited electron microscopy of cholangiocarcinomas provided no eviden...

Frequencies of liver neoplasia in a feral fish population and associated carcinogens

Abstract Previous research had documented prevalent liver neoplasia within feral fish populations from half a dozen polluted waterways of North America.1–3 A brown bullhead, Ictalurus nebulosus, population in the Black River, Ohio, had a 33% prevalence of grossly observable liver tumors in fish older than 2 years compared to 0 % in 249 bullhead from a reference location (Buckeye Lake).4 To approximate the actual prevalence of gross plus microscopic lesions combined in the Black River population, we captured 125 bullhead at least 250 mm in length in 1982. Livers were preserved for histopathology and pectoral fin spines were removed for aging. On average, each liver was sectioned at five levels for diagnosis. Bullheads (whole fish) and Black River sediment were analyzed for polynuclear aromatic hydrocarbons (PAHs) by gas chromatography-mass spectrometry as previously reported.4,5 Bullheads were found to have a higher incidence of liver tumors than was grossly apparent and to contain elevated levels of polynuclear aromatic hydrocarbons (PAHs).

Cancer in Wild Freshwater Fish Populations with Emphasis on the Great Lakes

Abstract Reports of tumors in wild freshwater fish populations have been increasing. The highly industrialized nature of the Great Lakes basin suggests that chemically-induced tumors could occur in Great Lakes fish. Several indices of tumors in these fish are reviewed, including: thyroid hyperplasia, gonadal neoplasm, papillomas, skin tumors, and tumors of the liver. The results of this study show that papillomas in white sucker, gonadal tumors in carp x goldfish hybrids, and hyperplasia in coho salmon are widespread in the Great Lakes. Tumor incidence is proposed as a sensitive indicator of the level of carcinogenic compounds in the environment.

The use of tumors in wild populations of fish to assess ecosystem health

Evidence has linked toxicants in aquatic systems with cancer in fish and population level effects on species. Thus some types of tumors may be useful monitors of ecosystem health, at least as affected by genotoxins and promoters. However, tumors caused by purely genetic mechanisms or by virus would not be good indicators. Only neoplasms which have chemicals as a portion of their etiology (either as initiators or promoters) would be useful in assessing ecosystem health. Lesions which may fit these criteria include liver neoplasms (both biliary and hepatic) and skin lesions in a variety of primarily benthic fishes, and neural lesions in various drum species and in butterfly fish species. Two studies purporting to demonstrate a lack of tumors in fish from polluted areas have been reexamined and found either to have insufficient data on vulnerable species or to actually support a tumor-pollution linkage. Thus certain lesions in vulnerable species or species groups may serve as a mechanism to assess one facet of ecosystem health.

Analysis of fish bile with HPLC - fluorescence to determine environmental exposure to benzo(a)pyrene

Brown bullhead from the Black River, Ohio, have a high incidence of liver neoplasia which is associated with elevated concentrations of polynuclear aromatic hydrocarbons (PAHs) in the sediment. We evaluated the use of biliary concentrations of benzo(a)pyrene [B(a)P] equivalents as a means for determining PAH exposure. Bile was collected from 16 brown bullheads and 8 common carp taken from each of two Lake Erie tributaries in Ohio, the industrialized Black River and the non-industrialized Old Woman Creek. Hatchery bullhead (n = 8) were used to determine base levels of PAHs. A high performance liquid chromatography (HPLC) — fluorescence technique was used to determine the concentration of B(a)P equivalents in the bile samples. The area of all peaks fluorescing at 380/430 nm was summed to give a single value for B(a)P equivalents in each sample. Concentrations of B(a)P equivalents generally reflected concentrations of PAH in sediment where fish were collected. Bile taken from Black River carp contained the highest concentration of B(a)P equivalents and was significantly different from all other groups. The value obtained for Black River bullhead was also high and was found to be significantly different from hatchery bullhead. B(a)P equivalents varied between carp and bullhead from the same habitat possibly because of differing food habits or metabolic pathways. However, our results indicate that relative levels of B(a)P equivalents in the bile of fish correspond well to B(a)P levels in sediment and may offer a means of determining environmental exposure of fish to the parent compound.

Evaluation of Effects Caused by High Copper Concentrations in Torch Lake, Michigan, on Reproduction of Yellow Perch

Abstract Elevated concentrations of copper are present in Torch Lake, Michigan, an Environmental Protection Agency Superfund site. The sauger ( Stizostedion canadense ) population in Torch Lake has been extirpated and walleye ( Stizostedion vitreum ) populations are maintained by stocking. We used yellow perch ( Perca flavescens ) to determine if chronic exposure to elevated copper concentrations has reduced the reproductive success of percids. Ripe yellow perch from Torch Lake and Gratiot Lake, a reference site, were captured between 6 May and 6 June 1990. Crosses were made within each lake and between lakes (both combinations); five pairs of each type were attempted. Portions of each egg mass were reared in Torch Lake water (34 ng/mL copper) and reference site water (Rice Lake) until 4 days posthatch (20-d to 28-d). Copper concentrations were found to be over two times as high as in reference samples both in Torch Lake water and in gonads of perch from Torch Lake. The percentages of eggs hatched in Torch Lake and reference lake water were not significantly different, although a trend of reduced hatch in Torch Lake water was apparent. Likewise, no significant differences were indicated in hatching success among crosses. However, duration of hatching was significantly longer for Torch Lake egg masses than for reference lake egg masses, indicating that copper may affect reproductive success through disruption of hatch coordination with food availability or reduction of larval fitness.

Methodological considerations for conducting tumor surveys of fishes

The usefulness of tumor surveys in indicating the availability of carcinogenic contaminants in ecosystems hinges largely on decisions made during the planning process. Species used as indicator organisms for monitoring programs are best selected from those known to be susceptible to epizootics of neoplasms. Lesions which can be quickly located and preserved in the field and for which a data base exists to help interpretation include liver neoplasms and external neoplasms. Since tumor frequencies increase with age and may change from season to season, studies should hold these variables constant among locations. During the design of the study investigators should determine the number of fish they need to examine in order to achieve the degree of resolution desired. Finally the field crew must be familiar with fish anatomy and necropsy techniques as well as storage and handling of the chosen preservative.

A multi-metric assessment of environmental contaminant exposure and effects in an urbanized reach of the Charles River near Watertown, Massachusetts

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