ALBERT

Notes: Abstract. White Leghorn chicken (Gallus domesticus) eggs were injected prior to incubation with one of four concentrations (0.001, 0.01, 0.1, and 1.0 egg-equivalent) of an extract derived from 1,000 double-crested cormorant (Phalacrocorax auritus) eggs collected at Spider Island adjacent to Green Bay in Lake Michigan. One egg-equivalent corresponded to the concentration of contaminants present in an average cormorant egg. This was approximately 322 pg toxic equivalents (TEQs)/g, ww egg with polychlorinatedbiphenyl congener 126 (3,3′,4,4′,5-pentachlorobiphenyl) accounting for over 70% of the TEQs. Injection of 1.0 egg-equivalent resulted in 77% mortality at hatch. The incidence of developmental abnormalities (structural defects or edema) was not affected by injection of the extract. Body weight gain of chicks was reduced in the 1.0 egg-equivalent dose group in the first, second, and third week's post-hatch. Relative brain weights were greater and relative bursa weights were less in the 1.0 egg-equivalent dose group than in the vehicle control at three weeks of age. There were no significant differences in the relative weights of the heart, liver, spleen, testes, or comb among treated and control birds.

Notes: Abstract For the 1983 nesting season, Forster's tern (Sterna forsteri) reproductive success was significantly impaired on organochlorine contaminated Green Bay, Lake Michigan compared to a relatively uncontaminated inland location at Lake Poygan, Wisconsin. Compared with tern eggs from Lake Poygan, eggs from Green Bay had significantly higher median concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), other polychlorinated dibenzo-p-dioxins (PCDDs), total polychlorinated biphenyls (PCBs), total (three congeners) non-ortho, ortho' PCBs, five individual PCB congeners known to induce aryl hydrocarbon hydroxylase (AHH) and several other organochlorine contaminants. Conversions of analytical concentrations of TCDD and PCB congeners based on relative AHH induction potencies allowed for estimation of total 2,3,7,8-TCDD equivalents. Two PCB congeners, 2,3,3′,4,4′- and 3,3′,4,4′,5-pentachlorobiphenyl (PeCB) accounted for more than 90% of the median estimated TCDD equivalents at both Green Bay and Lake Poygan. The median estimated TCDD equivalents were almost 11-fold higher in tern eggs from Green Bay than in eggs from Lake Poygan (2175 and 201 pg/g). The hatching success of Green Bay sibling eggs from nests where eggs were collected for contaminant analyses was 75% lower at Green Bay than at Lake Poygan. Hatchability of eggs taken from other nests and artificially incubated was about 50% lower for Green Bay than for Lake Poygan. Among hatchlings from laboratory incubation, those from Green Bay weighed approximately 20% less and had a mean liver weight to body weight ratio 26% greater than those from Lake Poygan. In both field and laboratory, mean minimum incubation periods were significantly longer for eggs from Green Bay compared to Lake Poygan (8.25 and 4.58 days, respectively). Mean minimum incubation time for Green Bay eggs in the field was 4.37 days longer than in the laboratory. Hatchability was greatly improved when Green Bay eggs were incubated by Lake Poygan adults in an egg-exchange experiment, but was sharply decreased in Lake Poygan eggs incubated in Green Bay nests. Nest abandonment and egg disappearance were substantial at Green Bay but nil at Lake Poygan. Thus, not only factors intrinsic to the egg, but also extrinsic factors (parental attentiveness), impaired reproductive outcome at Green Bay. The epidemiological evidence from this study strongly suggested that contaminants were a causal factor. AHH-active PCB congeners (intrinsic effects) and PCBs in general (extrinsic effects) appeared to be the only contaminants at the concentrations measured in eggs, capable of producing the effects that were observed at Green Bay.

Notes: Abstract Fishes of the Great Lakes contain hazardous chemicals such as synthetic halogenated hydrocarbons and metals. These fish can move from the lakes into the Great Lakes tributaries of Michigan. In doing so, they transport concentrationsof contaminants which may represent a risk to wildlife. Concentrations of mercury (Hg), total polychlorinated biphenyls (PCBs), 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TCDD-EQ), total DDT complex, aldrin, endrin, dieldrin, heptachlor, heptachlor epoxide, lindane, hexachlorobenzene, cis-chlordane, oxychlordane, endosulfan-I, methoxychlor, trans-chlordane, and trans-nonachlor were determined in composite samples of fishes from above and below Michigan hydroelectric dams, which separate the fishes which have access to the Great Lakes from fishes that do not. Mean concentrations of total PCBs, TCDD-EQ, DDT, and most of the other pesticides were greater in composite samples of six species of fishes from below than above the dams on the Au Sable, Manistee, and Muskegon Rivers. Concentrations of mercury, were the same or greater above the dams than below. However, this difference was statistically significant only on the Au Sable. Mercury concentrations ranged from less than 0.05 mg/kg to 0.73 mg Hg/kg, ww. Total concentrations of PCBs ranged from 0.02 to 1.7 mg/kg, ww. Concentrations of 2,3,7,8-tetrachlordibenzo-p-dioxin equivalents varied among fishes and locations. The concentrations of TCDD-EQ ranged from 2.4 to 71 μg/kg, ww, with concentrations in carp being the greatest. Concentrations of TCDD-EQ were greater than the concentrations which would be expected to occur, due solely to the presence of polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF), and technical mixtures of PCBs.

Notes: Abstract Recently, there have been discussions of the relative merits of passage of fishes around hydroelectric dams on three rivers (Au Sable, Manistee, and Muskegon) in Michigan. A hazard assessment was conducted to determine the potential for adverse effects on bald eagles that could consume such fishes from above and below dams on the three primary rivers. The hazard assessments were verified by comparing the reproductive productivities of eagles nesting in areas where they ate primarily fish from either above or below dams on the three primary rivers, as well as on two additional rivers in Michigan, the Menominee and Thunder Bay. Concentrations of organochlorine insecticides (OCI), polychlorinated biphenyls (total PCBs), 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TCDD-EQ), and total mercury (Hg) were measured in composite samples of fishes from above and below hydroelectric dams on the Manistee and Muskegon Rivers, which flow into Lake Michigan, and the Au Sable River, which flows into Lake Huron. Mean concentrations of OCI, total PCBs, and TCDD-EQ were all greater in fishes from below the dams than in those from above. The hazard assessment indicated that current concentrations of Hg and OCI other than DDT (DDT + DDE + DDD) in fish from neither above nor below dams would present a significant hazard to bald eagles (Haliaeetus leucocephalus). Both total PCBs and TCDD-EQ in fishes from below the dams currently present a significant hazard to bald eagles, since their mean hazard quotients (HQ) were all greater than one.

Notes: Abstract Populations of mink (Mustela vison) have declined in many areas of the world. Such declines have been linked to exposures to synthetic, halogenated hydrocarbons. In the Great Lakes region, mink are fewer in areas along the shore of the Great Lakes and their tributaries where mink have access to fish from the Great Lakes. Recently, there has been discussion of the relative merits of passage of fishes around hydroelectric dams on rivers in Michigan. A hazard assessment was conducted to determine the potential for adverse effects on mink, which could consume such fishes from above or below dams on the rivers. Concentrations of organochlorine insecticides, polychlorinated biphenyls (PCBs), 2,3,7,8-tetrachloridibenzo-p-dioxin equivalents (TCDD-EQ), and total mercury were measured in composite samples of fishes from above or below hydroelectric dams on the Manistee and Muskegon Rivers, which flow into Lake Michigan, and the Au Sable River, which flows into Lake Huron. Concentrations of organochlorine insecticides, PCBs, and TCDD-EQ were all greater in fishes from below the dams than those from above. Concentrations of neither organochlorine insecticides nor mercury in fishes are currently a risk to mink above or below the dams. All of the species of fishes collected from downstream of the dams contained concentrations of PCBs and TCDD-EQ, which represent a hazard to mink. The hazard index for PCBs was less than one for the average of all species from the upstream reaches of the Manistee and Au Sable Rivers, but not the Muskegon. The hazard index (concentration in fish/NOAEC) was greater than 1 for all of the species collected from below the dams, in all three rivers. The greatest hazard index was observed for carp (Cyprinus carpio) downstream on the Muskegon River. Because the concentrations of PCBs used in the hazard assessment were corrected for relative toxic potencies, the hazard ratios based on PCBs should be similar to those based on TCDD-EQ. This was found to be true. Thus, either total PCBs or TCDD-EQ could be used as the critical toxicant in the hazard assessment. However, if uncorrected concentrations of PCBs, expressed as Aroclors®, were used in the hazard assessment, the toxicity of the weathered mixture would have been underestimated by approximately five-fold, and, in that instance, TCDD-EQ would be the critical contaminant for the hazard assessment. The average maximum allowable percentage of fish from above the dams, which would result in no observable adverse effects of TCDD-EQ, was 70%. Based on the average TCDD-EQ concentrations in the fishes, an average of 8.6% of the diet could be made up of fishes from below dams on the rivers. The most restrictive daily allowable intakes were for carp on the Muskegon and steelhead trout (Onchorhyncus mykiss) on the Manistee Rivers. Only 2.7% of the diet could be made up of these two species from influenced portion of the Au Sable River, they would be exposed to 390 μg PCBs and 8.55 ng of TCDD-EQ per day, respectively (Giesy et al. 1994b). Thus, it would take 15.1 or 77 days for mink to receive their total annual dose of PCBs or TCDD-EQ, respectively. At least for chinook salmon, the critical contaminant for the purposes of hazard assessment would be total concentrations of PCBs. Consuming chinook salmon for as little as 2 weeks would deliver the annual allowable dose of PCBs to mink.

Notes: Abstract The effects of consumption of environmental contaminants contained in carp (Cyprinus carpio) from Saginaw Bay, Michigan on various hematological parameters and liver integrity of adult female mink (Mustela vison) were determined. Mink were fed diets that contained 0 (control), 10, 20, or 40% carp prior to and throughout the reproductive period (182 days). The diets contained 0.015, 0.72, 1.53, and 2.56 mg polychlorinated biphenyls (PCBs)/kg diet and 1.0, 19, 40, and 81 pg 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs)/g diet, respectively. Mink fed the diets containing carp showed a general dose-dependent occurrence of clinical signs commonly associated with chlorinated hydrocarbon toxicity, including listlessness, nervousness when approached, anorexia, and melena. Erythrocyte counts were less in mink exposed to Saginaw Bay carp than in controls, while the number of white blood cells was greater than in controls. Significant differences (p〈0.05) in the concentrations of neutrophils, lymphocytes, monocytes, and eosinophils were also found between the control and carp-fed groups, but are considered to be of limited clinical or biological importance. Hematocrit values for the mink fed the 20 and 40% carp diets were significantly less than those of mink in the control and 10% carp groups. There were no significant differences in hemoglobin concentrations among the groups. Necropsies revealed enlarged yellowish livers in many of the carp-fed mink, especially those fed the 40% carp diet. Liver, spleen, and lung weights of carp-fed mink were significantly greater than those of control mink. Histopathologic examination of the livers revealed various degrees of congestion, hepatocellular fatty changes, and scattered portal lymphocytic infiltration which were most prevalent in mink fed the carp diets. These clinical signs, hematological effects, and histologic alterations are similar to those previously described for chlorinated hydrocarbon toxicoses in mink.

Notes: Abstract Carp (Cyprinus carpio) collected from Saginaw Bay, Michigan, containing 8.4 mg total polychlorinated biphenyls (PCBs)/kg and 194 ng of 2,3,7,8-tetrachloro-dibenzo-p-dioxin equivalents (TEQs)/kg, were substituted for marine fish at levels of 0, 10, 20, or 40% in the diets of adult ranch mink (Mustela vison). The diets, containing 0.015, 0.72, 1.53, and 2.56 mg PCBs/kg diet, or 1.03, 19.41, 40.02, and 80.76 ng TEQs/kg diet, respectively, were fed to mink prior to and throughout the reproductive period to evaluate the effects of a naturally-contaminated prey species on their survival and reproductive performance. The total quantities of PCBs ingested by the mink fed 0, 10, 20, or 40% carp over the 85-day treatment period were 0.34, 13.2, 25.3, and 32.3 mg PCBs/mink, respectively. The corresponding quantities of TEQs ingested by the mink over the same treatment period were 23, 356, 661, and 1,019 ng TEQs/mink, respectively. Consumption of feed by mink was inversely proportional to the PCB and TEQ content of the diet. The diets containing Saginaw Bay carp caused impaired reproduction and/or reduced survival of the kits. Compared to controls, body weights of kits at birth were significantly reduced in the 20 and 40% carp groups, and kit body weights and survival in the 10 and 20% carp groups were significantly reduced at three and six weeks of age. The females fed 40% carp whelped the fewest number of kits, all of which were stillborn or died within 24 hours. Lowest observable adverse effect levels (LOAEL) of 0.134 mg PCBs/kg body weight/day or 3.6 ng TEQs/kg body weight/day for adult female mink were determined. The potential effects of exposure of wild mink to contaminated Great Lakes fish were assessed by calculating “maximum allowable daily intakes” and “hazard indices” based on total concentrations of PCB residues in several species of Great Lakes fish and mink toxicity data derived from the study.