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Mercury trends in herring gull (Larus argentatus) eggs from Atlantic Canada, 1972–2008: Temporal change or dietary shift?
2013
Burgess, Neil M. | Bond, Alexander L. | Hebert, Craig E. | Neugebauer, Ewa | Champoux, Louise
Mercury (Hg) is a pervasive contaminant that can adversely affect predatory wildlife. Bird eggs provide insights into breeding females' Hg burdens, and are easily collected and archived. We present data on Hg trends in herring gull (Larus argentatus) eggs from five sites in Atlantic Canada from 1972 to 2008. We found a significant decrease in Hg at Manawagonish Island, New Brunswick and Île du Corossol, Quebec, but after correcting Hg for dietary shifts using stable isotopes (δ15N), these trends disappeared. Decreasing temporal trends of stable isotopes in gull eggs were observed at four sites, suggesting shifts in gull diets. At Gull Island, Newfoundland, diet-adjusted Hg increased from 1977 to 1992, dropped sharply between 1992 and 1996, and rose again from 1996 to 2008. After adjusting Hg trends for dietary shifts of herring gulls, it appears that environmental Hg in coastal ecosystems has remained relatively constant at most sites in Atlantic Canada over the last 36 years.
Afficher plus [+] Moins [-]Occurrence, source and ecological assessment of petroleum related hydrocarbons in intertidal marine sediments of the Bay of Fundy, New Brunswick, Canada
2018
Yang, Zeyu | Shah, Keval | Crevier, Charlotte | Laforest, Sonia | Lambert, Patrick | Hollebone, Bruce P. | Yang, Chun | Brown, Carl E. | Landriault, Mike | Goldthorp, Michael
Total petroleum hydrocarbons (TPH), n-alkanes, petroleum-related biomarkers of terpanes and steranes, and polycyclic aromatic hydrocarbons (PAHs) were analyzed in the intertidal sediments in the Bay of Fundy, Nova Scotia/New Brunswick, Canada. Sites close to the harbour and more densely populated areas had higher TPH levels than other pristine areas. n-Alkanes presented a typical single bell-shape in n-C₁₆ to n-C₃₅ range and an obvious odd to even carbon preference. Most sites had trace amounts of petroleum biomarkers. Abundant non-alkylated PAHs and lower amounts of alkylated PAHs represented the major input of the incomplete combustion of solid (e.g., coal, coke, biomass, and coal tar) and liquid fuels. The toxicity estimation for PAHs indicates that they did not have potential toxicity to benthic organisms at most sampling sites. However, possible to probable negative effects from the measured PAH concentrations were found for the two samples from Courtenay Bay and Saint Andrews.
Afficher plus [+] Moins [-]Mercury concentrations in marine sediments near a former mercury cell chlor-alkali plant in eastern Canada
2016
Walker, Tony R.
Concentrations of total mercury (THg) were measured in coastal marine sediments near a former chlor-alkali plant in Chaleur Bay, New Brunswick. The chlor-alkali plant has been a local point source of THg since operation began in 1963. Historical THg contamination of marine sediments and biota has been widely reported. No baseline assessment has been conducted following plant closure in 2008. Surface (0–2cm) oxidized marine sediments were sampled along a single 5.2km transect radiating from the former plant and analysed for THg. THg concentrations ranged from 0.04–0.28μgg−1. Some localised THg concentrations exceeded Canadian marine sediment quality guidelines (n=4), but all samples (n=14) were significantly lower than previous studies conducted during plant operation. Plant closure (source control) and natural sediment recovery likely responsible for attenuating THg concentrations, but burial in deeper anoxic sediments may increase bioavilability of Hg that could pose ecological risks to marine biota.
Afficher plus [+] Moins [-]Methylmercury in tissues of Atlantic sturgeon (Acipenser oxyrhynchus) from the Saint John River, New Brunswick, Canada
2018
Mallory, Mark L. | O'Driscoll, Nelson J. | Klapstein, Sara | Varela, José Luis | Ceapa, Cornell | Stokesbury, Michael J.
Environmental contamination by mercury is a concern in marine food webs, and especially for large fish. We examined methylmercury (MeHg) levels in blood, muscle and liver of 35 individual Atlantic sturgeon (Acipenser oxyrhynchus), a commercially harvested, anadromous fish eastern Canada. Females had higher blood and liver MeHg levels than males, and in some tissues there was a suggestion of higher mercury in longer fish. Collectively, sturgeon MeHg levels were far below Canadian and international guidelines for safe consumption of fish meat.
Afficher plus [+] Moins [-]Spatial and temporal distribution of heavy metal concentrations in mussels (Mytilus edulis) from the Baie des Chaleurs, New Brunswick, Canada
2011
Fraser, Marc | Surette, Céline | Vaillancourt, Cathy
Previous studies on heavy metal contamination of the Baie des Chaleurs focus only on industrial centers and overlooked the ecosystem as a whole. To fill this gap, the objective of this study is to establish a baseline of the spatio-temporal distribution of heavy metals in mussels from the Baie des Chaleurs based on the ecosystem approach. Our results show, for the first time, a cadmium contamination in mussels across the south coast of the Baie des Chaleurs and not only in industrial centers. Our results also confirm previous studies showing heavy metal contamination of the Belledune area. This study demonstrates that the use of the ecosystemic approach is essential to obtain a comprehensive picture of environmental contamination in marine ecosystems.
Afficher plus [+] Moins [-]Simulating sulfur dioxide plume dispersion and subsequent deposition downwind from a stationary point source: a model
1996
Bourque, C.P.A. | Arp, P.A. (Faculty of Forestry and Environmental Management, University of New Brunswick, Fredericton, New Brunswick E3B 6C2 (Canada))
Fish and seafood availability in markets in the Baie des Chaleurs region, New Brunswick, Canada: a heavy metal contamination baseline study
2013
Fraser, Marc | Surette, Céline | Vaillancourt, Cathy
The consumption of halieutic products has many health benefits. However, their contaminants loads need to be addressed to better understand the risk from consuming these products. The aquatic biota from the Baie des Chaleurs in New Brunswick is contaminated by cadmium, zinc and lead. In spite of this, no study has examined the heavy metal concentrations in commercial halieutic products sold in this Canadian region. The objective of this pilot study was to characterize the species and origin of fish and seafood sold in the Baie des Chaleurs region by using an ecosystemic approach. Additionally, a baseline picture of the heavy metal levels found in these products has been determined. In 2008, interviews were carried out in markets located in the Baie des Chaleurs area. Species that were identified as the most purchased were then bought for analysis. Samples were freeze-dried and homogenized before nitric acid digestions. Aluminum, copper, cadmium, iron, manganese, and zinc concentrations were determined by inductively coupled plasma optical emission spectrometry. Results show that 36 % of seafood species sold in markets were caught in the Baie des Chaleurs. Lobsters, shrimps, scallops and oysters are the most purchased species regardless of the season. High amounts of cadmium exceeding tolerable daily intake are found in lobster hepatopancreas and can cause deleterious effects on health, in particular in vulnerable populations such as children and heavy consumers. The ecosystemic approach to health used in this pilot study shows the feasibility of an exhaustive study on the exposure of coastal population to heavy metal from fish and seafood consumption and the source of halieutic products sold in markets.
Afficher plus [+] Moins [-]Distribution of aluminum in black spruce saplings growing on two New Brunswick forest soils with contrasting acid sulfate sorption
1989
Arp, P.A. (New Brunswick Univ., Fredericton, N.B. (Canada). Faculty of Forestry) | Akerley, C. | Mellerowicz, K.
Impacts of forests on water chemistry
1989
Mahendrappa, M.K. (Forestry Canada Maritimes Region, Fredericton, N.B. (Canada))