Relationships among mercury, selenium, and neurochemical parameters in common loons (Gavia immer) and bald eagles (Haliaeetus leucocephalus)

Fish-eating birds can be exposed to levels of dietary methylmercury (MeHg) known or suspected to adversely affect normal behavior and reproduction, but little is known regarding Hg's subtle effects on the avian brain. In the current study, we explored relationships among Hg, Se, and neurochemical receptors and enzymes in two fish-eating birds--common loons (Gavia immer) and bald eagles (Haliaeetus leucocephalus). In liver, both species demonstrated a wide range of total Hg (THg) concentrations, substantial demethylation of MeHg, and a co-accumulation of Hg and Se. In liver, there were molar excesses of Se over Hg up to about 50-60 microg/g THg, above which there was an approximate 1:1 molar ratio of Hg:Se in both species. However, in brain, bald eagles displayed a greater apparent ability to demethylate MeHg than common loons. There were molar excesses of Se over Hg in brains of bald eagles across the full range of THg concentrations, whereas common loons often had extreme molar excesses of Hg in their brains, with a higher proportion of THg remaining as MeHg compared with eagles. There were significant positive correlations between brain THg and muscarinic cholinergic receptor concentrations in both species studied; whereas significant negative correlations were observed between N-methyl-D-aspartic acid (NMDA) receptor levels and brain Hg concentration. There were no significant correlations between brain Se and neurochemical receptors or enzymes (cholinesterase and monoamine oxidase) in either species. Our findings suggest that there are significant differences between common loons and bald eagles with respect to cerebral metabolism and toxicodynamics of MeHg and Se. These interspecies differences may influence relative susceptibility to MeHg toxicity; however, neurochemical responses to Hg in both species were similar.

Lead concentrations in ruffed grouse, rock ptarmigan, and willow ptarmigan in Québec

Between 1996 and 1998, ruffed grouse, spruce grouse, willow ptarmigan, and rock ptarmigan harvested by hunters in Québec were examined for lead contamination. On examination of the gizzards of these birds, lead shot was found only in ruffed grouse (1.2%). The probability of ingestion of lead shot by grouse and ptarmigans is low. Analyses of the lead concentrations in the wing bones of grouse and ptarmigans and in the muscle tissue of ptarmigans were conducted. Although differences were observed between individuals based on age and sex, the mean concentrations measured were in the range of those that occur naturally at background levels (<6 microg/g dw). Lead concentrations in muscle tissue were low, often at the limit of detection. However, the few high concentrations detected were probably related to a lead pellet or bullet fragment. Based on an analysis of the health risk associated with consumption of ptarmigan muscle, we conclude that the use of lead ammunition for hunting gallinaceous birds may pose an unnecessary risk of lead poisoning because of the possible ingestion of lead shot, bullets, fragments or embedded shot.

Ichthyophonus-like infection in wild amphibians from Québec, Canada

Myositis associated with infection by Ichthyophonus-like organisms was diagnosed in 35 of 260 (13%) wild amphibians collected in Quebec, Canada, from 1959 to 1964 (n = 30), and 1992 to 1999 (n = 230). Infection was diagnosed in 17 green frogs Rana clamitans, 9 wood frogs R. sylvatica, 4 red-spotted newts Notophthalmus viridescens, 3 bullfrogs R. catesbeiana, 1 spring peeper Pseudacris crucifer, and 1 pickerel frog R. palustris. The spring peeper and one of the bullfrogs were collected in 1964 from the Mont Saint-Hilaire Biosphere Reserve, indicating long-term presence of the organism. Spores of the organisms invaded striated muscle fibers and were associated with variable degrees of granulomatous and eosinophilic inflammation. Infection was considered fatal in 2 green frogs, 1 wood frog, and 1 red-spotted newt. It was considered potentially significant in 3 additional green frogs in which up to 100% of the fibers of some muscles were replaced by spores associated with a severe granulomatous reaction. Ultrastructural features of Ichthyophonus-like spores included a thick trilaminated wall, a paramural cytoplasm, multiple nuclei, oval mitochondria with short tubulo-vesicular cristae and numerous ribosomes. This report represents 4 new host records and shows that ichthyophonosis is enzootic in amphibians from Quebec.

Acquiescence to adjunctive experimental therapies may relate to psychological distress: pilot data from a bone marrow transplant center

Use of alternative therapy for breast cancer outside of the hospital setting has been identified as a marker of psychological distress. Whether acquiescence to experimental therapies within the medical setting might also be a sign of psychological distress is not well known. We therefore evaluated patients with breast cancer undergoing bone marrow transplantation (BMT), an experimental method for treatment, to determine if acquiescence to further adjunctive experimental therapy related to psychological distress. In order to do this, we studied psychological test results of 42 breast cancer patients undergoing BMT at the University of Florida between January and December 1997. These tests included the Medical Outcomes Short Form Health Survey, the Beck Depression Inventory, the State-Trait Anxiety Inventory and the Medical Coping Modes Questionnaire. Women who accepted adjunctive experimental therapy had significantly higher trait anxiety and poorer role functioning compared to women who did not (both P < 0.001). These findings suggest that psychological distress may be a factor in medical decision-making even within the medical setting and that prospective research in this area is warranted.

Mercury Accumulation and Biomagnification in Ospreys (Pandion haliaetus) in the James Bay and Hudson Bay Regions of Québec

Mercury exposure was examined in adults and nestlings of ospreys (Pandion haliaetus) from lakes, rivers, and hydroelectric reservoirs in northern Québec between 1989 and 1991 by assessing the amount of mercury transferred from fish to ospreys, which are voracious fish-eaters. The high mercury concentrations detected in adult feathers and tissues (feathers, blood, liver, kidneys, muscles, brain) of nestlings indicate an increase in mercury availability at recently constructed hydroelectric reservoirs (10-12 years for the La Grande-2 Reservoir). With mean total mercury levels of 37.3 mg/kg and 1.9 mg/kg in feathers (dry weight) and in blood (wet weight), respectively, contamination rates were, in both tissues, five times higher for chicks born near the La Grande Reservoirs (western sector) than in those reared in natural habitats. Furthermore, the mean quantity of total mercury in 40-day-old chicks reared near a reservoir was 10.5 mg, compared with to 1.6 mg for those reared in a natural environment. Modeling of mercury transfer from fish to osprey nestlings showed that the mercury level in chicks' blood provides a good estimate of mercury concentrations in ingested food. In addition, the relationship between mercury concentrations in the blood and that in feathers indicates that substantial biomagnification of mercury occurs from the ingested dose to the feathers. The intensity of this biomagnification varies with the age of the chicks and reaches a maximum value as the flight feathers start to form (at 20-25 days of age) declining thereafter until the bird is 45 days old and growth of those feathers is complete. Nevertheless, the mean number of young fledged on reservoirs where mercury exposure is greatest (>40 mg/kg of Hg in chicks' feathers) did not differ (1.6 +/- 0.7) from that observed elsewhere in built-up environments (1.9 +/- 0.7) or in natural habitats (2.0 +/- 0.7) (H = 4.39; p = 0.11). Storage of mercury in growing feathers (86% of all mercury in osprey) prevents accumulation in living tissues, thereby protecting the chick from related toxic effects. However, toxicological problems may arise after fledging. In particular, attention should be paid to postfledging survival before concluding that mercury exposure is insufficiently high in Osprey young reared at reservoirs.

Dioxin-like compounds in fishing people from the Lower North Shore of the St. Lawrence River, Quebec, Canada

In this study, investigators assessed exposure to dioxin-like compounds in a fishing population that inhabits small coastal communities along the Lower North Shore of the St. Lawrence River, Quebec. This population relies heavily on wildlife foods for sustenance. Investigators analyzed chemically the most popular marine foods (i.e., fish, crustaceans, sea mammals, and sea-bird eggs), and they also obtained 25 human plasma samples from individuals in two villages along the river. The mean level of total polychlorinated biphenyls in this population was approximately twice that found in the entire fishing cohort. Plasma levels of dioxin-like compounds, expressed as tetrachlorodibenzodioxin toxic equivalents, were approximately eight times higher than levels in urban residents. Most of the increase in tetrachlorodibenzodioxin toxic equivalents in the selected fish eaters resulted primarily from an elevation in polychlorinated biphenyls. Concentrations of dioxin-like compounds from the Lower North Shore were low in fish and seals, but concentrations were elevated in the eggs of sea birds. Given that there was also a significant statistical correlation in the entire population between human plasma levels and consumption of birds' eggs-and not other traditional foods-much of the increased human dose appeared to originate from this one food source. Because there appear to be increased, but uncertain, health risks from this elevated body burden, investigators advised the residents of the area to avoid consumption of wild birds' eggs (i.e., a food source of minor nutritional importance).

Hindlimb deformities (ectromelia, ectrodactyly) in free-living anurans from agricultural habitats

High prevalences of hindlimb deformities were recorded in wild-caught green frogs (Rana clamitans), northern leopard frogs (Rana pipiens), American toads, (Bufo americanus), and bullfrogs (Rana catesbeiana) from agricultural sites exposed to pesticide runoff in the St. Lawrence River Valley of Québec, Canada, between July and September 1992 and 1993. Of 853 metamorphosing anurans examined in 14 farmland habitats, 106 (12%; range 0 to 69%) had severe degrees of ectromelia and ectrodactyly, compared to only two (0.7%; range 0 to 7.7%) of 271 in 12 control sites. However, the variation in the proportion of deformities among sites was too large to conclude that there was a significant difference between control and pesticide-exposed habitats. Clinical signs varied and were characterized by segmental hypoplasia or agenesis of affected limbs. Conspicuous abnormalities interfered with swimming and hopping, and likely constituted a survival handicap. Because of circumstances and the frequency of these malformations in nine distinct habitats, and in three different species from one of our study sites, we propose a teratogenic action of exogenous factors. Despite the fact that many biotic and abiotic agents are potentially harmful to limb development, agricultural contaminants were suspected as primary aggressors. Thus, clinical examination and frequency of deformities in anurans might be an economical screening tool to assess ecosystem health and the presence of environmental contaminants.

Marketing to the Homosexual (gay) market: a profile and strategy implications

This article describes a significant market to which marketers must devote greater attention. The gay market is well-educated, has high discretionary income, is informed socially and politically, is dedicated to career and home ownership, and places greater importance on friendship networks than do most Americans. Although a potentially lucrative market segment, gays represent a difficult segment to reach since alienation by other segments could be an explosive factor for many businesses.

Contamination of local wildlife following a fire at a polychlorinated biphenyls warehouse in St Basile le Grand, Quebec, Canada

This study on wildlife contamination, one to ten months after the polychlorinated biphenyls (PCB) fire in St Basile le Grand, Quebec, shows that the fire increased PCB and polychlorinated dibenzofuran (PCDF) levels in animals. From the data, it was not possible to detect a significant increase in polychlorinated dibenzodioxin (PCDD) levels after the fire. Given the relatively small sample size, the differences in concentrations could not be estimated precisely. However, it can be asserted with a 95% confidence level that mean concentrations of total PCBs were roughly 2 to 6 times higher in the area contaminated by the plume of smoke, concentrations of homologues with 3 chlorine atoms were 1 to 4 times higher, and levels of homologues with 5 to 9 chlorine atoms were 3 to 13 times higher. The relative deviations between concentrations in areas under the plume and those outside it were similar for all animals sampled. With regard to total PCDFs, mean concentrations were significantly higher under the smoke plume than outside it for all species. This observation is linked to homologues with 4, 5 and 7 chlorine atoms for which significant differences were detected between the two areas. The fire had no effect on the pattern of PCB congeners found in the tissue of animals in the region. Congeners Nos. 153, 180, 138 and 118 represent approximately 50% of total PCBs. Although PCB and PCDF concentrations were higher in the tissue of local wildlife species exposed to the fire, they were nonetheless comparable to those found in other urban and agricultural areas in Canada. These concentrations, in 2,3,7,8-TCDD toxic equivalents, were much lower than those observed in the wake of three other major incidents involving PCDDs (Elgin, Florida; Times Beach, Missouri; and Seveso, Italy).(ABSTRACT TRUNCATED AT 250 WORDS)

β-carotene and retinoids in eggs of Great Blue Herons (Ardea herodias) in relation to St Lawrence River contamination

: The potential use of retinoids and β-carotene as biomarkers in the eggs of the Great Blue Heron was investigated. In the spring of 1991, 65 eggs were collected from nine heronries (seven along the St Lawrence River and two reference sites). A method was specifically developed for the extraction and analysis of β-carotene and the retinoids in heron egg yolks by reversed-phase HPLC. When results were expressed either as the molar ratio of retinol: retinyl palmitate or as retinyl palmitate concentration, significant differences were found between colonies; however, retinyl palmitate concentration was deemed the better biomarker because it was not significantly influenced by embryonic stage of development. Retinyl palmitate concentrations in freshwater colonies were negatively related to PCB congeners Nos 105 and 118 as well as their TCDD-EQ values (p < 0.02, r (2)=0.78). Egg tetrachloro-mono-ortho biphenyl concentrations were also negatively related to retinyl palmitate (p < 0.005, r (2)=0.90). With the exception of the two mono-ortho co-planar congeners detected in the present study, the contamination levels found in heron eggs were well below those found for other bird species in the Great Lakes area and, so far, no detrimental effects have been reported in Great Blue Heron populations in Quebec. These results suggest that retinyl palmitate may be useful as a sensitive and non-invasive biomarker for monitoring organochlorine contaminant effects in the Great Blue Heron in freshwater sites.

Colonic bull's-eye lesions in histiocytosis X

A 27-year-old woman with known pulmonary, cutaneous and osseous histiocytosis X presented with vague abdominal pain. Double-contrast barium enema examination revealed multiple colonic bull's-eye lesions. Biopsy showed histiocytic infiltration similar to that already described at other sites in this patient (the lungs and bone). To the authors' knowledge, this case represents the first radiologic description of this manifestation of histiocytosis X. Though rare, it should be considered in the differential diagnosis of colonic bull's-eye lesions.

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For the most part, doctors working in Quebec's local community service centres (or CLSCs) receive a fixed amount for their services. This type of remuneration is often associated with employee status. In the case of the CLSC doctors, however, their status is determined by the nature of their relationship with the centre's administration. It is evident from the conditions under which they practise that the CLSC doctors are not employees. Their autonomy is determined by the mission, orientation, and operation of the centre in a way that is similar to that of doctors paid on a fee-for-services basis in the province's hospital centres.

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