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Bibliography of the Maurice Lamontagne Institute

Charles GOBEIL

SMITH, J.N., K. LEE, C. GOBEIL, R.W. MACDONALD, 2009. Natural rates of sediment containment of PAH, PCB and metal inventories in Sydney Harbour, Nova Scotia. Sci. Total Environ., 407: 4858-4869 .

Analyses of metal and organic contaminants were carried out on 41 sediment cores, dated using 210Pb and 137Cs, from the heavily industrialized region of Sydney Harbour, N.S. to evaluate the history of contamination and to predict the rates of natural containment of the harbour by sediment burial. Geochronologies for metals (eg. Pb, As) and polycyclic aromatic hydrocarbons (PAHs) are correlated with the development of the steel and coke industries in the Sydney region while polychlorinated biphenyl (PCB) geochronologies reflect the disposal of electrical equipment used in the steel mill/coking operations. Pb was derived mainly from atmospheric emissions and its concentration has declined exponentially with time in harbour sediments since the closure of the steel mill/coke ovens in the 1980s with a time constant of about 15 years. This represents the time scale for the circulation of this particle-associated contaminant in transient catchment basins prior to permanent deposition in the sediments. PAH and PCB sediment concentrations have also declined exponentially with time since the 1980s, but with a smaller time constant of 10 years owing to the fact that they enter the harbour directly with steel mill and coke oven effluent rather than through atmospheric pathways. Since the time dependence for the burial of metal and organic inventories can be modeled by first order processes, future contaminant levels can be predicted for surface sediments in Sydney Harbour. Mean sediment concentrations of metal and organic contaminants in the upper 5 cm throughout most of the harbour are predicted to decline to levels below the effects range-medium (above which organisms are very likely to be negatively affected by the presence of a contaminant) by 2030. Crown Copyright ©2009 Published by Elsevier B.V.

DESJARDINS, C., C. GOBEIL, B. SUNDBY, 2006. Suitability of fish scales as archives of temporal variations in ambient mercury levels in estuaries. Estuar. Coasts, 29(5): 855-859 .

To examine the suitability of fish scales as a historical archive of environmental mercury (Hg) contamination, we analyzed a collection of scales taken from striped bass (Morone saxatilis) captured in the St. Lawrence Estuary between 1944 and 1962. The total mass of Hg in individual scales increases linearly with the weight of the scale, suggesting that Hg is well preserved in the scale tissue. Age, length, and sex of specimens captured during the same year did not significantly influence the concentration of Hg in the scales. The average Hg concentrations in scales of specimens captured in 1956 (53.2 ± 9.1 ng g-1 and 1962 (58.6 ± 7.7 ng g-1) are nearly twice as high as in scales from 1951 (30.2 ± 3.0 ng g-1). These results follow the trend revealed in sediment cores from the St. Lawrence Estuary. A high level of Hg in scales from 1945 (68.7 ± 18.4 ng g-1) could have been caused by an episode of Hg contamination around 1945 not recorded in the sediment or by a diet-related change in Hg exposure.©2006 Estuarine Research Federation

ROULEAU, C., C. GOBEIL, H. TJÄLVE, 2006. Cadmium accumulation in coastal demersal fish. Mar. Ecol. Prog. Ser., 311: 131-143 .

The hepatic Cd burden, measured on 291 individuals of 4 species of demersal fish (Gadus morhua, Reinhardtius hippoglossoides, Hippoglossoides platessoides, and Raja radiata), is 2 to 5 times higher in fish from the open Gulf of St. Lawrence than in fish from the St. Lawrence Estuary, 600 km landward. The higher Cd burden in the open Gulf is not related to the input of anthropogenic Cd, nor can it be attributed to differences in size, sex, sampling season, or state of health. Rather, the Cd burden in demersal fish may be related to sediment diagenesis, since the concentration of authigenic Cd (i.e. Cd minerals formed in the sediments) is higher in the Gulf than in the Estuary, which may lead in turn to Cd-enrichment in sediment-dwelling organisms. Measured Cd burdens in the liver agree with predictions made with a simple biokinetic model that uses realistic estimates of the Cd content of benthic invertebrates in combination with kinetic parameters determined in H. platessoides with in vivo gamma counting. These results strongly suggest that the Cd content of the diet, rather than of the water phase, determines the hepatic Cd burden in these demersal fish species.©2006 Inter-Research

GILBERT, D., B. SUNDBY, C. GOBEIL, A. MUCCI, G.-H. TREMBLAY, 2005. A seventy-two-year record of diminishing deep-water oxygen in the St. Lawrence estuary: the northwest Atlantic connection. Limnol. Oceanogr., 50(5): 1654-1666 .

Oxygen concentrations in the bottom waters of the Lower St. Lawrence estuary (LSLE) decreased from 125 αmol L-1 (37.7 % saturation) in the 1930s to an average of 65 αmol L-1 (20.7 % saturation) for the 1984-2003 period. A concurrent 1.65 °C warming of the bottom water from the 1930s to the 1980s suggests that changes in the relative proportions of cold, fresh, oxygen-rich Labrador Current Water (LCW) and warm, salty, oxygen-poor North Atlantic Central Water (NACW) in the water mass entering the Laurentian Channel probably played a role in the oxygen depletion. We estimate that about one half to two thirds of the oxygen loss in the bottom waters of the LSLE can be attributed to a decreased proportion of LCW. This leaves between one third and one half of the oxygen decrease to be explained by causes other than changes in water mass composition. An increase in the along-channel oxygen gradient from Cabot Strait to the LSLE over the past decades, combined with data from sediment cores, suggests that increased sediment oxygen demand may be partly responsible for the remainder of the oxygen decline. In July 2003, approximately 1,300 km2 of seafloor in the LSLE was bathed in hypoxic water (<62.5 αmol L-1).©2005 The American Society of Limnollogy and Oceanography

GOBEIL, C., B. RONDEAU, L. BEAUDIN, 2005. Contribution of municipal effluents to metal fluxes in the St. Lawrence River. Environ. Sci. Technol., 39(2): 456-464 .

The contribution of urban effluents to the total metal fluxes carried toward the sea by the St. Lawrence, a major world river, is 60 % for Ag; 8-13 % for Cu, Zn, Mo, Cd, and Bi; and less than 3 % for all other measured elements (Al, V, Cr, Mn, Fe Co, Ni, As, Rb, Sr, Zr, Cs, Ba, W, Re, Pb, Th, U). This is inferred from measurements at the Montreal wastewater treatment plant. Except for Ag, municipal effluents do not weigh heavily on the St. Lawrence River metal budget, likely because of the physical-chemical primary treatment applied to most effluents. Compared to direct atmospheric deposition on the surface of the river, effluents would contribute half as much Pb and one-tenth as much Zn. In contrast, effluents deliver twice as much Cd and six times as much Cu as the atmosphere. Stable Pb isotope ratios (206Pb/207Pb, 206Pb/208Pb) in suspended particulate matter from the river indicate that the total Pb content in the river water is three times higher than the pristine level. The ratios of Cr, Ni, Cu, Zn, and Cd to Al in suspended particulate matter are high as compared to pre-industrial sediments, which suggests that trace element fluxes are higher today. To decrease metal levels in the St. Lawrence River further will be a challenge since the sources of metals are not well-known.©2005 American Chemical Society

SUNDBY, B., P. MARTINEZ, C. GOBEIL, 2004. Comparative geochemistry of cadmium, rhenium, uranium, and molybdenum in continental margin sediments. Geochim. Cosmochim. Acta, 68: 2485-2493 .

The concentrations of authigenic phases of Cd, Re, U, and Mo increase with depth in four 45-cm-long sediment box cores collected along the axis of the Laurentian Trough, Gulf of St. Lawrence. Average authigenic accumulation rates, estimated from element inventories, are similar to rates in other continental margin environments. Strong regional variations in sediment accumulation rate and sulfide concentration have little influence on the accumulation rates of Cd and Re. This suggests that slow precipitation kinetics controls the accumulation of Cd and Re in these sediments. The accumulation rate of authigenic U is more variable; it may be tied to the kinetics of microbially mediated U reduction and be controlled by the availability of reactive organic matter. Authigenic Mo is distinguished by a sharp subsurface concentration minimum, above which Mo cycles with manganese. Mo released to pore water upon reduction of Mn oxides diffuses downward and enriches the subsurface sediment. Mo accumulates most rapidly in the sediment with the highest sulfide content. Slow conversion of molybdate to thiomolybdate may explain the much slower Mo accumulation rate in the less sulfidic sediments. A component of authigenic Mo accumulates with pyrite in an approximately constant Mo:Fe ratio. The accumulation rate of pyrite and associated Mo is insensitive to AVS abundance. Pyrite formation may be limited by the reactivity of iron oxide minerals.©2004 Elsevier Ltd

SUNDBY, B., A. MUCCI, C. GOBEIL, D. GILBERT, Y. GRATTON, P. ARCHAMBAULT, 2002. Hypoxia in the Deep Waters of the Laurentian Trough, Lower St. Lawrence Estuary. Pages 29-31 in J.J. Martin (ed.). Developments for a Canadian GEOHAB (Global Ecology and Oceanography of Harmful Algal Blooms) program: 2001 Workshop report. Rapp. tech. can. sci. halieut. aquat., 2400 .

GOBEIL, C., B. SUNDBY, R.W. MACDONALD, J.N. SMITH, 2001. Recent change in organic carbon flux to Arctic Ocean deep basins : evidence from acid volatile sulfide, manganese and rhenium discord in sediments. Geophys. Res. Lett., 28(9): 1743-1746 .

GOBEIL, C., R.W. MACDONALD, J.N. SMITH, L. BEAUDIN, 2001. Atlantic water flow pathways revealed by lead contamination in Arctic Basin sediments. Science (Wash.), 293: 1301-1304 .

MACDONALD, R.W., L.A. BARRIE, T.F. BIDLEMAN, M.L. DIAMOND, D.J. GREGOR, R.J.SEMKIN, W.M.J. STRACHAN, Y.F. LI, F. WANIA, M. ALAEE, L.B. ALEXEEVA, S.M. BACKUS, R. BAILEY, J.M. BEWERS, C. GOBEIL, C.J. HALSALL, T. HARNER, J.T. HOFF, L.M.M. JANTUNEN et al., 2000. Contaminants in the Canadian Arctic: 5 years of progress in understanding sources, occurrence and pathways. Sci. Total Environ., 254: 93-234 .

ROULEAU, C., C. GOBEIL, H. TJALVE, 2000. Accumulation of silver from the diet in two marine Benthic predators : the snow crab (Chionoecetes opilio) and american plaice (Hippoglossoides platessoides). Environ. Toxicol. Chem., 19(3): 631-637 .

TAKAYANAGI, K., C. GOBEIL, 2000. Dissolved Aluminium in the Upper St. Lawrence Estuary. J. Oceanogr., 56: 517-525 .

COSSA, D., C. GOBEIL, 2000. Mercury speciation in the lower St. Lawrence estuary. Can. J. Fish. Aquat. Sci., 57 (Suppl. 1): 138-147 .

Mercury speciation was determined in the water column and sediment pore waters of the Lower St. Lawrence Estuary, and total Hg (HgT) was measured in seven biological species, including pelagic and demersal fish and crustaceans. In water, HgT concentrations ranged from 1.8 to 7.8 pM, with the highest levels in surface waters and the lowest in deep waters (1.8-2.9 pM). HgT concentrations in sediment pore waters were 10 times as high, with methyl mercury levels of 5.1-14.4 pM. Reactive Hg (HgR) generally accounted for around 20 ppt of HgT in the water column and lower than 30 ppt in pore waters. The distribution of elemental Hg and HgR suggests that Hg(II) is reduced in surface waters and that inorganic Hg is mobilized during remineralization of organic matter at the sediment surface. In the biota, concentrations ranged between 0.05 and 0.89 nmol•g-1(wet weight). Feeding habits and habitats account for these observations. Results suggest that the sediment is the main source of Hg contamination for the biota. A mass balance calculation showed that the Hg flux entering the lower estuary from the St. Lawrence River is equivalent to the amount buried in estuarine sediments.

GOBEIL, C., R.W. MACDONALD, J.N. SMITH, 1999. Mercury profiles in sediments of the Arctic ocean basins. Environ. Sci. Technol., 33: 4194-4198 .

LEBEUF, M., I. ST-PIERRE, Y. CLERMONT, C. GOBEIL, 1999. Concentrations de biphényles polychlorés (BPC) et de pesticides organochlorés chez trois espèces de poissons de fond de l'estuaire et du golfe du Saint-Laurent et du fjord du Saguenay. Rapp. stat. can. sci. halieut. aquat., 1059, 108 p .

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Concentrations of polychorinated biphenyls (PCBs) and organochlorine pesticides were determined in muscle and liver of Atlantic cod (Gadus morhua), American plaice (Hippoglossoides platessoides) and Greenland halibut (Reinhardtius hippoglossoides), which were sampled from the Estuary and Gulf of St. Lawrence, and from the Saguenay Fjord. The analyses included measurements of more than 35 organochlorine compounds, including approximately twenty PCB congeners, in 56 tissue samples. This report summarises data from over 1 900 individual measurements. All of the tissues contain measurable quantities of most of the PCBs and organochlorine pesticides. All fish have higher levels of contaminants in liver compared to muscle tissue. Liver concentrations are highest in cod and lowest in plaice, while concentrations in muscle are highest in halibut and lowest in cod. Regardless of the species, concentrations of contaminants are similar in samples from the Saguenay and the Estuary but are generally higher than in samples from the northeastern Gulf. According to the Canadian guidelines for the protection of human health, levels of total PCB and of DDT and its metabolites in fish tissues should not exceed 2 000 and 5 000 ng/g (wet weight), respectively. The levels of PCBs and organochlorine pesticides measured in muscle and liver samples of cod, plaice and halibut in this study are less than these guidelines. In fish livers, the highest concentrations of PCBs are less than one-half of the guideline, while levels of DDT and its metabolites are less than one-tenth of the guideline. In fish muscle, concentrations are up to 10 and 100 times lower than the guidelines, for PCBs and for DDT and its metabolites, respectively.

PELLETIER, É., G. CANUEL, J. PADROS, Y. CLERMONT, C. GOBEIL, 1999. Concentrations d'hydrocarbures aromatiques polycycliques chez quatre espèces de poissons de fond et deux espèces de crustacés de l'estuaire et du golfe du Saint-Laurent et du fjord du Saguenay. Rapp. stat. can. sci. halieut. aquat., 1052, 20 p .

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This report summarizes work done conjointly by INRS-Océanologie (Université du Québec, Rimouski, Québec) and the Maurice Lamontagne Institute (Department of Fisheries and Oceans, Mont-Joli, Québec) to determine levels of polycyclic aromatic hydrocarbons (PAHs) in Atlantic cod (Gadus morhua), American plaice (Hippoglossoides platessoides), thorny skate (Raja radiata), Greenland halibut (Reinhardtius hippoglossoides), and northern shrimp (Pandalus borealis) from the Estuary and Gulf of St. Lawrence as well as in snow crab (Chionoecetes opilio) from the St. Lawrence Estuary and the Saguenay Fjord. The specific compounds that we tried to detec were fluoranthe, pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene, benco(a)pyrene, dibenzo(a,h,)anthracene, benzo(g,h,i)perylene, naphtalen, acenaphtene, fluorene, phenanthrene, and anthracene. Concentrations of all PAHs in the muscle tissue of cod (n=12), plaice (n=12), skate n=6), and halibut (n=6) were below the analytical detection limits. With the exception of benzo[a]anthracene, concentrations of PAHS were also below detection limits in halibut liver tissue (n=9) and crab hepatopancreas (n=9). In contrast, shrimp muscle (n=12) contained measurable levels of fluoranthene, pyrene, benzo[a]anthracene, phenanthrene, and anthracene. The presence of benzo[a]anthracene in shrimp muscle, halibut liver, and crab hepatopancreas detected by fluorimetry was not confirmed by the mass spectroscopy equipment used due to the very low levels. This study concludes that the concentrations of PAHs in the analyzed species are always very low, or even non detected, and consequently, considered safe for human consumption.

ROULEAU, C., C. GOBEIL, H. TJÄLVE, 1999. Pharmacokinetics and distribution of dietary tributyltin and methylmercury in the snow crab (Chionoecetes opilio). Environ. Sci. Technol., 33: 3451-3457 .

GOBEIL, C., 1999. Silver in sediments from the St. Lawrence River and Estuary and the Saguenay Fjord. Environ. Sci. Technol., 33: 2953-2957 .

GOBEIL, C., B. SUNDBY, R.W. MARDONALD, J.N. SMITH, 1998. Pulsed sedimentation in the Arctic Ocean : implications for the preservation of organic matter. Mineralog. Mag., 62(A): 529-530 .

ROULEAU, C., C. GOBEIL, H. TJÄLVE, 1998. Pharmacokinetics and distribution of dietary tributyltin compared to those of methylmercury in the American plaice Hippoglossoides platessoides. Mar. Ecol. Prog. Ser., 171: 275-284 .

MACDONALD, R.W., S.M. SOLOMON, R.E. CRANSTON, H.E. WELCH, M.B. YUNKER, C. GOBEIL, 1998. A sediment and organic carbon budget for the Canadian Beaufort Shelf. Mar. Geol., 144: 255-273 .

ANSCHUTZ, P., S. ZHONG, B. SUNDBY, A. MUCCI, C. GOBEIL, 1998. Burial efficiency of phosphorus and the geochemistry of iron in continental margin sediments. Limnol. Oceanogr., 43: 53-64 .

SAINT-LOUIS, R., C. GOBEIL, É. PELLETIER, 1997. Le tributylétain et ses produits de dégradation dans l'estuaire du Saint-Laurent (Canada). Environ. Technol., 18(12): 1209-1218 .

GOBEIL, C., Y. CLERMONT, G. PAQUETTE, 1997. Concentrations en mercure, plomb et cadmium chez diverses espèces de poissons de fond, de poissons pélagiques et de crustacés de l'estuaire et du golfe du Saint-Laurent et du fjord du Saguenay. Rapp. stat. can. sci. halieut. aquat., 1011, 88 p .

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Concentrations of mercury, lead, and cadmium were determined in the muscle of northern shrimp (Pandalus borealis), in the muscle and hepatopancreas of snow crab (Chionoecetes opilio), and in the muscle, liver, and gonads of several fish species from the Estuary and Gulf of St. Lawrence and from the Saguenay Fjord. The fish species include Atlantic cod (Gadus morhua), Greenland halibut (Reinhardtius hippoglossoides), deepwater redfish (Sebastes mentella), American plaice (Hippoglossoides platessoides), thorny skate (Raja radiata), capelin (Mallotus villosus), Atlantic herring (Clupea harengus), and rainbow smelt (Osmerus mordax). The mercury concentrations in tissues of all species were 2 to 10 times lower than the Canadian guideline established to ensure human health protection, with the exception of those in the northern shrimp and snow crab from the Saguenay Fjord, which were near the guideline. Lead concentrations were low, and did not differ markedly, regardless of the species or the tissue, or whether it was from the gulf, the estuary or the fjord. Cadmium concentrations in fish muscle and gonads and in crustacean muscle were also low regardless of the location. However, as often observed, cadmium levels were higher in fish livers and snow crab hepatopancreas.

GOBEIL, C., R.W. MACDONALD, B. SUNDBY, 1997. Diagenetic separation of cadmium and manganese in suboxic continental margin sediments. Geochim. Cosmochim. Acta, 61: 4647-4654 .

COSSA, D., M. COQUERY, C. GOBEIL, J.-M. MARTIN, 1996. Mercury fluxes at the ocean margins. Pages 229-247 in W. Baeyens et al (ed.). Global and regional mercury cycles : sources, fluxes and mass balances. Kluwer Academic Publishers .

LEBEUF, M., C. GOBEIL, C. BROCHU, S. MOORE, 1996. Direct atmospheric deposition versus fluvial inputs of PCDD/Fs to the sediments of the Lower St. Lawrence Estuary. Organohalogen Compounds, 28: 20-24 .

LEBEUF, M., C. GOBEIL, Y. CLERMONT, C. BROCHU, S. MOORE, 1995. Non-ortho chlorobiphenyls in fish and sediments of the Estuary and Gulf of St. Lawrence. Organohalogen Compounds, 26: 421-426 .

GOBEIL, C., W.K. JOHNSON, R.W. MACDONALD, C. SHING WONG, 1995. Sources and burden of lead in St. Lawrence Estuary sediments : isotopic evidence. Environ. Sci. Technol., 29: 193-201 .

LEBEUF, M., C. GOBEIL, C. BROCHU, S. MOORE, 1995. Polychlorinated dibenzo-p-dioxins and dibenzofurans in Laurentian Trough sediments, lower St. Lawrence Estuary. Organohalogen Compounds, 24: 293-298 .

COSSA, D., C. GOBEIL, 1994. Un profil de distribution verticale des concentrations en mercure dans les eaux du bassin intérieur du fjord du Saguenay. Page 105 in J.-M. Sévigny & C.M. Couillard (éd.). Le fjord du Saguenay : un milieu exceptionnel de recherche. Ministère des pêches et des océans (Rapp. manus. can. sci. halieut. aquat., 2270) .

GOBEIL, C., D. COSSA, 1993. Mercury in sediments and sediment pore water in the Laurentian Trough. Can. J. Fish. Aquat. Sci., 50: 1794-1800 .

SUNDBY, B., C. GOBEIL, N. SILVERBERG, A. MUCCI, 1992. The phosphorus cycle in coastal marine sediments. Limnol. Oceanogr., 37: 1129-1145 .

GOBEIL, C., M. LEBEUF, 1992. Inventaire de la contamination des sédiments du chenal Laurentien : les biphényles polychlorés. Rapp. tech. can. sci. halieut. aquat., 1851, 45 p .

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The vertical distribution of polychlorinated biphenyls (PCBs) has been studied in the sediments of the Laurentian Trough, Lower St. Lawrence Estuary. The concentrations of PCBs in the Trough sediments is ten times lower than that of the sediments in Lake Ontario. Contrary to observations in Lake Ontario, PCBs accumulation in the Laurentian Trough sediments has not decreased in recent years. The mean accumulation rate of PCBs in the deep sediments of the Lower Estuary in the last decade is evaluated to similar to 450 kg/a. This value represents a large proportion of the PCB flux in the St. Lawrence River at Quebec City.

MACDONALD, R.W., D.M. MACDONALD, M.C. O'BRIEN, C. GOBEIL, 1991. Accumulation of heavy metals (Pb, Zn, Cu, Cd), carbon and nitrogen in sediments from Strait of Georgia, B.C. Mar. Chem., 34: 109-135 .

MACDONALD, R.W., E.C. CARMACK, F.A. McLAUGHLIN, D. SIEBERG, M.C. O'BRIEN, D. PATON, R. PEARSON, YANG LIANGFENG, C. GOBEIL, 1991. Oceanographic data collected from the Henry Larsen in the Beaufort Sea, August - September 1990. Can. Data Rep. Hydrogr. Ocean Sci., 97, 142 p .

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A cruise to the Southern Beaufort Sea was carried out from the Henry Larsen in August - September, 1990. Here we report the bottle data for measurements of salinity, temperature, nutrients (silicate, phosphate and nitrate), dissolved oxygen and chlorophyll a determinations, and the CTD data.

GOBEIL, C., D. PATON, F.A. McLAUGHLIN, R.W. MACDONALD, G. PAQUETTE, Y. CLERMONT, M. LEBEUF, 1991. Données géochimiques sur les eaux interstitielles et les sédiments de la mer de Beaufort. Rapp. stat. can. hydrogr. sci. océan., 101, 92 p .

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Five sediment box-cores were collected in the Beaufort Sea in September 1990. This report contains the results of the analyses showing the vertical distributions of nutrients (PO4- 3, SiO4- 4, NO3- plus NO2-, NO2-, NH4+, sulfate, chloride, iron and manganese in the porewaters. The vertical profiles of phosphorus, biogenic silicon, carbon, nitrogen, some metals (Mn, Fe, Al, Cd, Pb, Zn) and 210-lead in the solid phase are also included.

GOBEIL, C., 1991. Inventaire de la contamination des sédiments du chenal Laurentien : données sur les métaux et les éléments nutritifs. Rapp. stat. can. sci. halieut. aquat., 854, 63 p .

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This report contains analytical results showing the vertical distribution of several metals (Pb, Cd, Hg, Zn, Cu, Mn, Fe, Al, Ca, Mg), pyrite iron, phosphorus and biogenic silicon in Laurentian Trough sediments. The distribution of some of these metals (Pb, Cd, Cu, Mn, Fe) and the nutrients (PO4-3, NO3- plus NO2-, SiO4-4, NH4+) in the porewater of the sediments are also included. This research was carried out as a part of the St. Lawrence Action Plan. (DBO).

TREMBLAY, G.-H., C. GOBEIL, 1990. Dissolved arsenic in the St. Lawrence Estuary and the Saguenay Fjord, Canada. Mar. Pollut. Bull., 21: 465-469 .

COSSA, D., G.-H. TREMBLAY, C. GOBEIL, 1990. Seasonality in iron and manganese concentrations of the St. Lawrence River. Sci. Total Environ., 97/98: 185-190 .

GOBEIL, C., N. SILVERBERG, 1989. Early diagenesis of lead in Laurentian Trough sediments. Geochim. Cosmochim. Acta, 53: 1889-1896 .

COSSA, D., C. GOBEIL, P. COURAU, 1988. Dissolved mercury behaviour in the St. Lawrence Estuary. Estuar. Coast. Shelf Sci., 26: 227-230 .

GOBEIL, C., D. COSSA, 1987. Discharge of dissolved fluoride from the St. Lawrence River into the ocean. Pages 295-299 in E.T. Degens, S. Kempe & G. Weibin (ed.). Transport of carbon and minerals in major world rivers, part 4 (Mitt. Geol. Palaontol. Inst. Univ. Hamburg, 64) .

GOBEIL, C., N. SILVERBERG, B. SUNDBY, D. COSSA, 1987. Cadmium diagenesis in Laurentian Trough sediments. Geochim. Cosmochim. Acta, 51: 589-596 .