Download or read book Historical Trends of Polychlorinated Dibenzo p dioxins and Dibenzofurans in Fish and Sediment Associated with Two Bleached Kraft Pulp Mills in Northern Ontario written by Shari Cater and published by . This book was released on 2013 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the early 1990s polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) contamination of fish was widely associated with bleached kraft pulp mills. Regulations were put into place in Canada and elsewhere to reduce or eliminate the presence of these chemicals in pulp mill effluents. The industry quickly introduced treatment and process changes such as elemental (ECF) and total chlorine free (TCF) bleaching, which resulted in dramatically reduced PCDD/F concentrations in pulp mill effluents. However, PCDD/Fs may remain a concern for the receiving environment near bleached kraft pulp mills due to their tendency to persist in sediments and bioaccumulate in aquatic biota. Several studies conducted in the early 1990s reported significantly elevated levels of PCDD/Fs in white sucker (Catostomus commersoni) exposed to bleached kraft mill effluent (BKME). Particularly high concentrations were observed in the receiving environment of two mills in northern Ontario. The first mill, located in the town of Terrace Bay, discharges effluent into Jackfish Bay, Lake Superior. The second mill is located in Smooth Rock Falls, Ontario and discharges effluent into the Mattagami River where effects have been observed in fish collected downstream of the pulp mill. Over time, both mills have undergone a number of process upgrades, including a transition to 100% chlorine dioxide (ClO2) substitution. In 2006 the Tembec Smooth Rock Falls Pulp and Paper Mill closed permanently, while the mill in Terrace Bay has gone through a number of temporary shutdowns and is currently in the process of transitioning to a dissolving pulp process. Temporal changes in PCDD/F contamination was examined in white sucker historically exposed to BKME in Jackfish Bay and the Mattagami River, following mill process changes and closures. Historical data was summarized from studies conducted in the 1990s and analyzed along with liver tissue of male white sucker collected from each location in 2011 and 2012. The body burden of each fish was analysed using Toxic Equivalency (TEQ) calculations to account for concentration and relative toxicity of 2,3,7,8??? substituted PCDD/F congeners. At Jackfish Bay, concentrations of PCDD/Fs in surface sediment and dated sediment cores were used to document the spatial and temporal pattern of PCDD/F contamination in relation to historical process upgrades and operational changes at the mill. PCDD/Fs measured in white sucker liver samples collected from Jackfish Bay during gonadal recrudescence in the fall illustrate a decrease in mean TEQ from 74.2 ?? 20.9 pg???g-1 in 1991 to 3.34 ?? 2.05 pg???g-1 in 2012. These values were slightly elevated compared to the remote reference location at Mountain Bay, Lake Superior, which exhibited a mean TEQ of 1.88 ?? 0.45 pg???g-1 and 1.06 ?? 0.69 pg???g-1 in white sucker collected in fall 2011 and 2012, respectively. Although below consumption guidelines, trace levels of PCDD/Fs persist in fish collected from Jackfish Bay and these concentrations are suspected to reflect sediment contamination in Moberly Bay (part of Jackfish Bay). A unique PCDD/F contaminant profile, dominated by 2,3,7,8??? tetrachlorodibenzo???p???dioxin (TCDD) and dibenzofuran (TCDF), was observed in white sucker and sediment collected from Jackfish Bay. Analysis of surface sediment collected throughout Jackfish Bay revealed elevated PCDD/F concentrations, compared to reference areas in Lake Superior. TEQ values measured in surface sediment from the depositional areas of Moberly Bay exceeded the Canadian Council of Ministers of the Environment (CCME) guidelines. In 1991 PCDD/F contamination, reported as mean TEQ, of white sucker collected downstream of the pulp mill outfall in Smooth Rock Falls reached levels of 111 ?? 86.2 pg???g-1. At the time, the mill utilized molecular chlorine (Cl2) in the bleaching sequence and employed primary effluent treatment. A dramatic decline was observed in PCDD/F concentrations of fish collected in 1993 and 1995, corresponding to implementation of 100% ClO2 substitution in the bleaching process. PCDD/F contamination in white sucker collected from the Mattagami River in 2011 and 2012 were similar upstream (0.53???1.49 pg TEQ???g-1) and downstream (0.75???2.87 pg TEQ???g-1) of the historical pulp mill outfall at Smooth Rock Falls, suggesting a return to background condition following the 2006 mill closure. Levels of 2,3,7,8???TCDD and 2,3,7,8???TCDF in liver tissue of fish collected downstream declined drastically compared to concentrations measured in 1991. The PCDD/F congener profile observed in white sucker downstream in 2011 and 2012 was more similar to fish collected from the reference site upstream than exposed fish collected in 1991. No sediment depositional areas suitable for taking a core sample were found on the river downstream of Smooth Rock Falls due to the nature of the system. This study supports the conclusion that particulate (POM) and dissolved organic matter (DOM) from continuous inputs of effluent were likely the primary source of PCDD/Fs to fish in these receiving environments, with only a small contribution from surface sediment. Results indicate a decreasing trend in PCDD/F contamination of white sucker historically exposed to bleached kraft pulp mill effluent in the receiving environments of Jackfish Bay and the Mattagami River, consistent with mill process upgrades to eliminate the use of elemental chlorine from the bleaching sequence. Current levels of PCDD/Fs measured in white sucker collected from these locations suggest a return to background condition.
Download or read book Environmental Contaminants in Fish written by Derek C. G. Muir and published by The Study. This book was released on 1997 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: Summarizes levels of polychlorinated dioxins and furans in fish observed in various studies on the Peace and Athabasca rivers in Alberta and assesses temporal trends in these contaminants by comparison with previously published data. Begins with background information on chlorinated dioxins and furans, and describes site locations, sampling, and field and laboratory methodologies used. Spatial trends in relation to industrial pollution sources are also noted and risks to humans, fish, and wildlife are evaluated. Fish species analyzed include longnose sucker, burbot, mountain whitefish, and northern pike.
Download or read book Polychlorinated Dibenzo p dioxins and furans PCDDs PCDFs Sources and Environmental Impact Epidemiology Mechanisms of Action Health Risks written by Stephen Safe and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polychlorinated Dibenzodioxins and -furans (PCDDs and PCDFs) are potent environmental toxins. Environmental exposures to these compounds in part-per-billion (ppb) and part-per-trillion (ppt) concentrations are of particular interest. These exposures may arise from bleached paper products, paper production process sludge, effluent waste water from paper plants, consumption of food and water from contaminated sources and contact to paper products.
Download or read book Pollution Abstracts written by and published by . This book was released on 1995 with total page 454 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Contaminants in Environmental Samples written by Georgine M. Pastershank and published by The Study. This book was released on 1995 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report provides an interpretation of analytical results for dioxins and furans in water, biofilm, sediment, invertebrates, and fish samples collected on the Athabasca and Peace Rivers in 1992. The analysis focused on the partitioning, fate, and bioaccumulation of the two compounds having the greatest potential to accumulate in animal tissue, namely 2,3,7,8-tetrachloro dibenzo-p-dioxin and 2,3,7,8-tetrachloro dibenzofuran, in order to assist in the assessment of ecosystem health and long-term effects. The report compares the levels of these compounds found upstream and downstream from pulp and paper mills, and compares the detected levels to the limits recommended under the Canadian Environmental Quality Guidelines (for sediment and water) and Health Canada guidelines (for fish tissue).
Download or read book Temporal Trends in Polychlorinated Dibenzo p dioxins and Dibenzo furans Dioxin like PCBS and Polybrominated Diphenyl Ethers in Niagra River Suspended Sediments written by and published by . This book was released on 2005 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Temporal Trends in Polychlorinated Dibenzo p dioxins and Dibenzofurans Dioxin like PCBS and Polybrominated Diphenyl Ethers in Niagara River Suspended Sediments written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Archived suspended sediment samples collected over the period 1980-2002 at Niagara-on-the-Lake in the Niagara River were analyzed to assess temporal trends in contaminants associated with historical industrial activities in the watershed (PCDDs/PCDFS, DLPCBs), compared to more modern industrial chemicals (PBDEs)"--Abstract.
Download or read book Polychlorinated Dibenzo p dioxins and furans PCDDs PCDFs Sources and Environmental Impact Epidemiology Mechanisms of Action Health Risks written by Stephen Safe and published by Springer. This book was released on 1990-12-18 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polychlorinated Dibenzodioxins and -furans (PCDDs and PCDFs) are potent environmental toxins. Environmental exposures to these compounds in part-per-billion (ppb) and part-per-trillion (ppt) concentrations are of particular interest. These exposures may arise from bleached paper products, paper production process sludge, effluent waste water from paper plants, consumption of food and water from contaminated sources and contact to paper products.
Download or read book Dioxins in the Environment written by Great Britain. Interdepartmental Working Group on Polychlorinated Dibenzo-para-dioxins and Polychlorinated Dibenzofurans and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chlorinated Dioxin Trends Between 1987 and 1993 for Samples of Crab Hepatopancreas from Pulp and Paper Mill and Harbour Sites in British Columbia written by and published by . This book was released on 1995 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chlorinated Dioxin Trends Between 1987 and 1993 for Samples of Crab Hepatopancreas from Pulp and Paper Mill and Harbour Sites in British Columbia written by M. B. Yunker and published by . This book was released on 1995 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study employs principal components analysis (PCA) to explore the interrelationships and trends in both the chlorinated dibenzo-p-dioxin and dibenzofuran patterns and the toxic congener composition among British Columbia pulp and paper mill sites, and between harbours and mill sites. The researchers applied PCA to a large data set of the concentrations of dioxins and furans in samples of crab hepatopancreas from locations in the vicinity of British Columbia coastal mills and the principal harbours in the province. PCA distinguishes harbour samples from mill samples, reveals differences between individual mill sites, and reliably classifies the dioxin and furan congener patterns according to chlorine bleaching, digested polychlorinated phenol, and pentachlorophenol wood preservative sources. PCA is also used to assign sources to individual crab samples. The study results indicate the changes in dioxin and furan congener composition over time.
Download or read book QA QC guidance for sampling and analysis of sediments water and tissues for dredged material evaluations chemical evaluations written by and published by DIANE Publishing. This book was released on 1995 with total page 297 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Planar PCB Hazards to Fish Wildlife and Invertebrates written by Ronald Eisler and published by . This book was released on 1996 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dioxin Treatment Technologies written by and published by Office of Technology Assessment. This book was released on 1991 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hormonally Active Agents in the Environment written by National Research Council and published by National Academies Press. This book was released on 2000-02-03 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt: Some investigators have hypothesized that estrogens and other hormonally active agents found in the environment might be involved in breast cancer increases and sperm count declines in humans as well as deformities and reproductive problems seen in wildlife. This book looks in detail at the science behind the ominous prospect of "estrogen mimics" threatening health and well-being, from the level of ecosystems and populations to individual people and animals. The committee identifies research needs and offers specific recommendations to decision-makers. This authoritative volume: Critically evaluates the literature on hormonally active agents in the environment and identifies known and suspected toxicologic mechanisms and effects of fish, wildlife, and humans. Examines whether and how exposure to hormonally active agents occursâ€"in diet, in pharmaceuticals, from industrial releases into the environmentâ€"and why the debate centers on estrogens. Identifies significant uncertainties, limitations of knowledge, and weaknesses in the scientific literature. The book presents a wealth of information and investigates a wide range of examples across the spectrum of life that might be related to these agents.
Download or read book Toxicological Profile for Chlorodibenzofurans written by and published by . This book was released on 1994 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ecological Impacts of Toxic Chemicals written by Francisco Sánchez-Bayo, Paul J. van den Brink, Reinier M. Mann and published by Francisco Sanchez-Bayo. This book was released on 2011-09-09 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ecological Impacts of Toxic Chemicals presents a comprehensive, yet readable account of the known disturbances caused by all kinds of toxic chemicals on both aquatic and terrestrial ecosystems. Topics cover the sources of toxicants, their fate and distribution through the planet, their impacts on specific ecosystems, and their remediation by natural systems. Each chapter is written by well-known specialists in those areas, for the general public, students, and even scientists from outside this field. The book intends to raise awareness of the dangers of chemical pollution in a world dominated by industry and globalization of resources. Because the problems are widespread and far reaching, it is hoped that confronting the facts may prompt better management practices at industrial, agricultural and all levels of management, from local to governmental, so as to reduce the negative impacts of chemical contaminants on our planet.
