Peter G. C. Campbell

Bio: Peter G. C. Campbell is an academic researcher from Institut national de la recherche scientifique. The author has contributed to research in topics: Perch & Biotic Ligand Model. The author has an hindex of 61, co-authored 239 publications receiving 21731 citations. Previous affiliations of Peter G. C. Campbell include Université du Québec & Syngenta.

Sequential extraction procedure for the speciation of particulate trace metals

Abstract: An analytical procedure involving sequential chemicai extractions has been developed for the partitioning of particulate trace metals (Cd, Co, Cu, Ni, Pb, Zn, Fe, and Mn) into five fractions: exchangeable, bound to carbonates, bound to Fe-Mn oxides, bound to organic matter, and residual. Experimental results obtained on replicate samples of fluvial bottom sediments demonstrate that the relative standard deviation of the sequential extraction procedure Is generally better than =10%. The accuracy, evaluated by comparing total trace metal concentrations with the sum of the five Individual fractions, proved to be satisfactory. Complementary measurements were performed on the Individual leachates, and on the residual sediments following each extraction, to evaluate the selectivity of the various reagents toward specific geochemical phases. An application of the proposed method to river sediments is described, and the resulting trace metal speciation is discussed.

The biotic ligand model : a historical overview

Abstract: During recent years, the biotic ligand model (BLM) has been proposed as a tool to evaluate quantitatively the manner in which water chemistry affects the speciation and biological availability of metals in aquatic systems. This is an important consideration because it is the bioavailability and bioreactivity of metals that control their potential to cause adverse effects. The BLM approach has gained widespread interest amongst the scientific, regulated and regulatory communities because of its potential for use in developing water quality criteria (WQC) and in performing aquatic risk assessments for metals. Specifically, the BLM does this in a way that considers the important influences of site-specific water quality. This journal issue includes papers that describe recent advances with regard to the development of the BLM approach. Here, the current status of the BLM development effort is described in the context of the longer-term history of advances in the understanding of metal interactions in the environment upon which the BLM is based. Early developments in the aquatic chemistry of metals, the physiology of aquatic organisms and aquatic toxicology are reviewed first, and the degree to which each of these disciplines influenced the development of water quality regulations is discussed. The early scientific advances that took place in each of these fields were not well coordinated, making it difficult for regulatory authorities to take full advantage of the potential utility of what had been learned. However, this has now changed, with the BLM serving as a useful interface amongst these scientific disciplines, and within the regulatory arena as well. The more recent events that have led to the present situation are reviewed, and consideration is given to some of the future needs and developments related to the BLM that are envisioned. The research results that are described in the papers found in this journal issue represent a distinct milestone in the ongoing evolution of the BLM approach and, more generally, of approaches to performing ecological assessments for metals in aquatic systems. These papers also establish a benchmark to which future scientific and regulatory developments can be compared. Finally, they demonstrate the importance and usefulness of the concept of bioavailability and of evaluative tools such as the BLM.

Calcium and dairy acceleration of weight and fat loss during energy restriction in obese adults.

Abstract: Objective: Increasing 1, 25-dihydroxyvitamin D in response to low-calcium diets stimulates adipocyte Ca2+ influx and, as a consequence, stimulates lipogenesis, suppresses lipolysis, and increases lipid accumulation, whereas increasing dietary calcium inhibits these effects and markedly accelerates fat loss in mice subjected to caloric restriction Our objective was to determine the effects of increasing dietary calcium in the face of caloric restriction in humans Research Methods and Procedures: We performed a randomized, placebo-controlled trial in 32 obese adults Patients were maintained for 24 weeks on balanced deficit diets (500 kcal/d deficit) and randomized to a standard diet (400 to 500 mg of dietary calcium/d supplemented with placebo), a high-calcium diet (standard diet supplemented with 800 mg of calcium/d), or high-dairy diet (1200 to 1300 mg of dietary calcium/d supplemented with placebo) Results: Patients assigned to the standard diet lost 64 ± 25% of their body weight, which was increased by 26% (to 86 ± 11%) on the high-calcium diet and 70% (to 109 ± 16% of body weight) on the high-dairy diet (p < 001) Fat loss was similarly augmented by the high-calcium and high-dairy diets, by 38% and 64%, respectively (p < 001) Moreover, fat loss from the trunk region represented 190 ± 79% of total fat loss on the low-calcium diet, and this fraction was increased to 501 ± 64% and 662 ± 30% on the high-calcium and high-dairy diets, respectively (p < 0001) Discussion: Increasing dietary calcium significantly augmented weight and fat loss secondary to caloric restriction and increased the percentage of fat lost from the trunk region, whereas dairy products exerted a substantially greater effect

Partitioning of trace metals in sediments: Relationships with bioavailability

Abstract: As a result of complex physical, chemical and biological processes, a major fraction of the trace metals introduced into the aquatic environment is found associated with the bottom sediments, distributed among a variety of physico-chemical forms. As these different metal forms will generally exhibit different chemical reactivities, the measurement of the total concentration of a particular metal provides little indication of potential interactions with the abiotic or biotic components present in the environment. In principle, the partitioning of sediment-bound metals could be determined both by thermodynamic calculations (provided equilibrium conditions prevail) and by experimental techniques. The modelling of sediment-bound metals is far less advanced than is that of dissolved species, primarily because the thermodynamic data needed for handling sediment-interstitial water systems are not yet available. The partitioning of a metal among various fractions obtained by experimental techniques (e. g., sequential extraction procedures) is necessarily operationally defined. These methods have, however, provided significant insight into the physico-chemical factors influencing the bioavailability of particulate trace metals; some of these factors are discussed.

Potential artifacts in the determination of metal partitioning in sediments by a sequential extraction procedure

Abstract: The partitioning of trace metals in sediments, as obtained with a sequential extraction procedure, may be affected by (i) the techniques used to preserve the sediments before analysis and (ii) the presence/absence of atmospheric oxygen during the extraction steps. No storage method tested completely preserved the initial chemical and physical characteristics of the sediments. Drying of the sediment (freeze-drying; oven-drying) should be avoided; acceptable preservation techniques include freezing or short-term wet storage (1-2/sup 0/C). Among the different metals (Cd, Co, Cr, Cu, Ni, Pb, Zn, Fe, and Mn), copper, iron, and zinc were particularly sensitive to sample pretreatment. For anoxic sediments, the maintenance of oxygen-free conditions during the extractions is of critical importance.

Trace elements in soils and plants

Abstract: Chapter 1 The Biosphere Chapter 2 The Anthroposphere Introduction Air Pollution Water Pollution Soil Plants Chapter 3 Soils and Soil Processes Introduction Weathering Processes Pedogenic Processes Chapter 4 Soil Constituents Introduction Trace Elements Minerals Organic Matter Organisms in Soils Chapter 5 Trace Elements in Plants Introduction Absorption Translocation Availability Essentiality and Deficiency Toxicity and Tolerance Speciation Interaction Chapter 6 Elements of Group 1 (Previously Group Ia) Introduction Lithium Rubidium Cesium Chapter 7 Elements of Group 2 (Previously Group IIa) Beryllium Strontium Barium Radium Chapter 8 Elements of Group 3 (Previously Group IIIb) Scandium Yttrium Lanthanides Actinides Chapter 9 Elements of Group 4 (Previously Group IVb) Titanium Zirconium Hafnium Chapter 10 Elements of Group 5 (Previously Group Vb) Vanadium Niobium Tantalum Chapter 11 Elements of Group 6 (Previously Group VIb) Chromium Molybdenum Tungsten Chapter 12 Elements of Group 7 (Previously Group VIIb) Manganese Technetium Rhenium Chapter 13 Elements of Group 8 (Previously Part of Group VIII) Iron Ruthenium Osmium Chapter 14 Elements of Group 9 (Previously Part of Group VIII) Cobalt Rhodium Iridium Chapter 15 Elements of Group 10 (Previously Part of Group VIII) Nickel Palladium Platinum Chapter 16 Elements of Group 11 (Previously Group Ib) Copper Silver Gold Chapter 17 Trace Elements of Group 12 (Previously of Group IIb) Zinc Cadmium Mercury Chapter 18 Elements of Group 13 (Previously Group IIIa) Boron Aluminum Gallium Indium Thallium Chapter 19 Elements of Group I4 (Previously Group IVa) Silicon Germanium Tin Lead Chapter 20 Elements of Group 15 (Previously Group Va) Arsenic Antimony Bismuth Chapter 21 Elements of Group 16 (Previously Group VIa) Selenium Tellurium Polonium Chapter 22 Elements of Group 17 (Previously Group VIIa) Fluorine Chlorine Bromine Iodine

Soil Sampling and Methods of Analysis

Abstract: SOIL SAMPLING AND HANDLING, G.T. Patterson and M.R. Carter Soil Sampling Designs, D. Pennock, T. Yates, and J. Braidek Sampling Forest Soils, N. Belanger and K.C.J. Van Rees Measuring Change in Soil Organic Carbon Storage, B.H. Ellert, H.H. Janzen, A.J. VandenBygaart, and E. Bremer Soil Sample Handling and Storage, S.C. Sheppard and J.A. Addison Quality Control in Soil Chemical Analysis, C. Swyngedouw and R. Lessard DIAGNOSTIC METHODS for SOIL and ENVIRONMENTAL MANAGEMENT, J.J. Schoenau and I.P. O'Halloran Nitrate and Exchangeable Ammonium Nitrogen, D.G. Maynard, Y.P. Kalra, and J.A. Crumbaugh Mehlich 3 Extractable Elements, N. Ziadi and T. Sen Tran Sodium Bicarbonate Extractable Phosphorus, J.J. Schoenau and I. P. O'Halloran Boron, Molybdenum and Selenium, G. M. Hettiarachchi and U. C. Gupta Trace Element Assessment, W.H. Hendershot, H. Lalande, D. Reyes, and D. MacDonald Readily Soluble Aluminum and Manganese in Acid Soils, Y.K. Soon, N. Belanger, and W.H. Hendershot Lime Requirement, N. Ziadi and T. Sen Tran Ion Supply Rates Using Ion Exchange Resins, P. Qian, J.J. Schoenau, and N. Ziadi Environmental Soil Phosphorus Indices, A.N. Sharpley, P.J.A. Kleinman and J.L. Weld Electrical Conductivity and Soluble Ions, J.J. Miller and D. Curtin SOIL CHEMICAL ANALYSES, Y.K. Soon and W.H. Hendershot Soil Reaction and Exchangeable Acidity, W.H. Hendershot, H. Laland,e and M. Duquette Collection and Characterization of Soil Solutions, J.D. MacDonald, N. Belanger, S. Sauve, F. Courchesne, and W.H. Hendershot Ion Exchange and Exchangeable Cations, W.H. Hendershot, H. Lalande, and M. Duquette Non-Exchangeable Ammonium, Y.K. Soon and B.C. Liang Carbonates, T.B. Goh and A.R. Mermut Total and Organic Carbon, J.O. Skjemstad and J.A. Baldock Total Nitrogen, P.M. Rutherford, W.B. McGill, C.T. Figueiredo, and J.M. Arocena Chemical Characterization of Soil Sulphur, C.G. Kowalenko and M. Grimmett Total and Organic Phosphorus, I.P. O'Halloran and B.J. Cade-Menum Characterization of Available P by Sequential Extraction, H. Tiessen and J.O. Moir Extractable Al, Fe, Mn, and Si, F. Courchesne and M.C. Turmel Determining Nutrient Availability in Forest Soils, N. Belanger, David Pare, and W.H. Hendershot Chemical Properties of Organic Soils, A. Karam SOIL BIOLOGICAL ANALYSES, E. Topp and C.A. Fox Cultural Methods for Soil and Root Associated Microorganisms, J.J. Germida and J.R. de Freitas Arbuscular Mycorrhiza, Y. Dalpe and C. Hamel Root Nodule Bacteria and Symbiotic Nitrogen Fixation, D. Prevost and H. Antoun Microarthropods, J.P Winter and V.M. Behan-Pelletier Nematodes, T.A. Forge and J. Kimpinski Earthworms, M.J. Clapperton, G.H. Baker and C.A. Fox Enchytraeids, S.M. Adl Protozoa, S.M. Adl, D. Acosta-Mercado, and D.H. Lynn Denitrification Techniques for Soils, C.F. Drury, D.D. Myrold, E.G. Beauchamp, and W.D.Reynolds Nitrification Techniques in Soil Systems, C.F. Drury, S.C. Hart, and X.M. Yang Substrate-Induced Respiration and Selective Inhibition as Measures of Microbial Biomass in Soils, V.L. Bailey, J.L. Smith, and H. Bolton Jr. Assessment of Soil Biological Activity, R.P.Beyaert and C.A. Fox Soil ATP, R.P. Voroney, G. Wen, and R.P. Beyaert Lipid-Based Community Analysis, K.E. Dunfield Bacterial Community Analyses by Denaturing Gradient Gel Electrophoresis (DGGE), E. Topp, Y.-C. Tien, and A. Hartmann Indicators of Soil Food Web Properties, T.A. Forge and M. Tenuta SOIL ORGANIC MATTER ANALYSES, E.G. Gregorich and M.H. Beare Carbon Mineralization, D.W. Hopkins Mineralizable Nitrogen, Denis Curtin and C.A. Campbell Physically Uncomplexed Organic Matter, E.G. Gregorich and M.H. Beare Extraction and Characterization of Dissolved Organic Matter, M.H. Chantigny, D.A. Angers, K. Kaiser, and K. Kalbitz Soil Microbial Biomass C, N, P and S, R.P. Voroney, P.C. Brookes, and R.P. Beyaert Carbohydrates, M.H. Chantigny and D.A. Angers Organic Forms of Nitrogen, D.C. Olk Soil Humus Fractions, D.W. Anderson and J.J Schoenau Soil Organic Matter Analysis by Solid-State 13C Nuclear Magnetic Resonance Spectroscopy, M. J. Simpson and C. M. Preston Stable Isotopes in Soil and Environmental Research, B.H. Ellert and L. Rock SOIL PHYSICAL ANALYSES, D.A. Angers and F.J. Larney Particle Size Distribution, D. Kroetsch and C. Wang Soil Shrinkage, C.D. Grant Soil Density and Porosity, X. Hao, B.C. Ball, J.L.B. Culley, M.R. Carter, and G.W. Parkin Soil Consistency: Upper and Lower Plastic Limits, R.A. McBride Compaction and Compressibility, P. Defossez, T. Keller and G. Richard Field Soil Strength, G.C. Topp and D.R. Lapen Air Permeability, C.D. Grant and P.H. Groenevelt Aggregate Stability to Water, D.A. Angers, M.S. Bullock, and G.R. Mehuys Dry Aggregate Size Distribution, F.J. Larney Soil Air, R.E. Farrell and J.A. Elliott Soil-Surface Gas Emissions, P. Rochette and N. Bertrand Bulk Density Measurement in Forest Soils, D.G. Maynard and M.P. Curran Physical Properties of Organic Soils and Growing Media: Particle Size and Degree of Decomposition, L.E. Parent and J. Caron Physical Properties of Organic Soils and Growing Media: Water and Air Storage and Flow Dynamics, J. Caron, D.E. Elrick, J.C. Michel, and R. Naasz SOIL WATER ANALYSES, W.D. Reynolds and G.C. Topp Soil Water Analyses: Principles and Parameters, W.D. Reynolds and G.C. Topp Soil Water Content, G.C. Topp, G.W. Parkin, and Ty P.A Ferre Soil Water Potential, N.J. Livingston and G.C. Topp Soil Water Desorption and Imbibition: Tension and Pressure Techniques, W.D. Reynolds and G.C. Topp Soil Water Desorption and Imbibition: Long Column, W.D. Reynolds and G.C. Topp Soil Water Desorption and Imbibition: Psychrometry, W.D. Reynolds and G.C. Topp Saturated Hydraulic Properties: Laboratory Methods, W.D. Reynolds Saturated Hydraulic Properties: Well Permeameter, W.D. Reynolds Saturated Hydraulic Properties: Ring Infiltrometer, W.D. Reynolds Saturated Hydraulic Properties: Auger-Hole, G.C. Topp Saturated Hydraulic Properties: Piezometer, G.C. Topp Unsaturated Hydraulic Properties: Laboratory Tension Infiltrometer, F.J. Cook Unsaturated Hydraulic Properties: Laboratory Evaporation, O.O. B. Wendroth and N. Wypler Unsaturated Hydraulic Properties: Field Tension Infiltrometer, W.D. Reynolds Unsaturated Hydraulic Properties: Instantaneous Profile, W.D. Reynolds Estimation of Soil Hydraulic Properties, F.J. Cook and H.P. Cresswell Analysis of Soil Variability, B.C. Si, R.G. Kachanoski, and W.D. Reynolds APPENDIX Site Description, G.T. Patterson and J.A. Brierley General Safe Laboratory Operation Procedures, P. St-Georges INDEX

Heavy Metals in Contaminated Soils: A Review of Sources, Chemistry, Risks and Best Available Strategies for Remediation

Abstract: Scattered literature is harnessed to critically review the possible sources, chemistry, potential biohazards and best available remedial strategies for a number of heavy metals (lead, chromium, arsenic, zinc, cadmium, copper, mercury and nickel) commonly found in contaminated soils. The principles, advantages and disadvantages of immobilization, soil washing and phytoremediation techniques which are frequently listed among the best demonstrated available technologies for cleaning up heavy metal contaminated sites are presented. Remediation of heavy metal contaminated soils is necessary to reduce the associated risks, make the land resource available for agricultural production, enhance food security and scale down land tenure problems arising from changes in the land use pattern.

Bee declines driven by combined stress from parasites, pesticides, and lack of flowers

Abstract: Bees are subject to numerous pressures in the modern world. The abundance and diversity of flowers has declined, bees are chronically exposed to cocktails of agrochemicals, and they are simultaneously exposed to novel parasites accidentally spread by humans. Climate change is likely to exacerbate these problems in the future. Stressors do not act in isolation; for example pesticide exposure can impair both detoxification mechanisms and immune responses, rendering bees more susceptible to parasites. It seems certain that chronic exposure to multiple, interacting stressors is driving honey bee colony losses and declines of wild pollinators, but such interactions are not addressed by current regulatory procedures and studying these interactions experimentally poses a major challenge. In the meantime, taking steps to reduce stress on bees would seem prudent; incorporating flower-rich habitat into farmland, reducing pesticide use through adopting more sustainable farming methods, and enforcing effective quarantine measures on bee movements are all practical measures that should be adopted. Effective monitoring of wild pollinator populations is urgently needed to inform management strategies into the future.