Skip header and navigation

Refine By

6 records – page 1 of 1.

The distribution and trends of persistent organic pollutants and mercury in marine mammals from Canada's Eastern Arctic.

https://arctichealth.org/en/permalink/ahliterature294561
Source
Sci Total Environ. 2018 Mar 15; 618:500-517
Publication Type
Journal Article
Review
Date
Mar-15-2018
Author
Tanya M Brown
Robie W Macdonald
Derek C G Muir
Robert J Letcher
Author Affiliation
Memorial University of Newfoundland, St. John's, Newfoundland A1B 3X9, Canada. Electronic address: tanya_brown@sfu.ca.
Source
Sci Total Environ. 2018 Mar 15; 618:500-517
Date
Mar-15-2018
Language
English
Publication Type
Journal Article
Review
Keywords
Animals
Aquatic Organisms
Arctic Regions
Atlantic Ocean
DDT - analysis
Dichlorodiphenyl Dichloroethylene - analysis
Environmental monitoring
Environmental Pollutants - analysis
Food chain
Halogenated Diphenyl Ethers - analysis
Mercury - analysis
Newfoundland and Labrador
Pesticides - analysis
Polychlorinated biphenyls - analysis
Seals, Earless
Ursidae
Abstract
Arctic contaminant research in the marine environment has focused on organohalogen compounds and mercury mainly because they are bioaccumulative, persistent and toxic. This review summarizes and discusses the patterns and trends of persistent organic pollutants (POPs) and mercury in ringed seals (Pusa hispida) and polar bears (Ursus maritimus) in the Eastern Canadian Arctic relative to the rest of the Canadian Arctic. The review provides explanations for these trends and looks at the implications of climate-related changes on contaminants in these marine mammals in a region that has been reviewed little. Presently, the highest levels of total mercury (THg) and the legacy pesticide HCH in ringed seals and polar bears are found in the Western Canadian Arctic relative to other locations. Whereas, highest levels of some legacy contaminants, including ?PCBs, PCB 153, ?DDTs, p,p'-DDE, ?CHLs, ClBz are found in the east (i.e., Ungava Bay and Labrador) and in the Beaufort Sea relative to other locations. The highest levels of recent contaminants, including PBDEs and PFOS are found at lower latitudes. Feeding ecology (e.g., feeding at a higher trophic position) is shaping the elevated levels of THg and some legacy contaminants in the west compared to the east. Spatial and temporal trends for POPs and THg are underpinned by historical loadings of surface ocean reservoirs including the Western Arctic Ocean and the North Atlantic Ocean. Trends set up by the distribution of water masses across the Canadian Arctic Archipelago are then acted upon locally by on-going atmospheric deposition, which is the dominant contributor for more recent contaminants. Warming and continued decline in sea ice are likely to result in further shifts in food web structure, which are likely to increase contaminant burdens in marine mammals. Monitoring of seawater and a range of trophic levels would provide a better basis to inform communities about contaminants in traditionally harvested foods, allow us to understand the causes of contaminant trends in marine ecosystems, and to track environmental response to source controls instituted under international conventions.
PubMed ID
29145101 View in PubMed
Less detail

Persistent organic pollutants in the polar regions and the Tibetan Plateau: A review of current knowledge and future prospects.

https://arctichealth.org/en/permalink/ahliterature301586
Source
Environ Pollut. 2019 May; 248:191-208
Publication Type
Journal Article
Review
Date
May-2019
Author
Xiaoping Wang
Chuanfei Wang
Tingting Zhu
Ping Gong
Jianjie Fu
Zhiyuan Cong
Author Affiliation
Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing, 100101, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address: wangxp@itpcas.ac.cn.
Source
Environ Pollut. 2019 May; 248:191-208
Date
May-2019
Language
English
Publication Type
Journal Article
Review
Keywords
Air Pollutants - analysis
Antarctic Regions
Arctic Regions
Climate change
Cold Climate
DDT
Environmental monitoring
Environmental Pollutants - analysis
Food chain
Forecasting
Hexachlorocyclohexane
Hydrocarbons, Chlorinated
Soil
Tibet
Abstract
Due to their low temperatures, the Arctic, Antarctic and Tibetan Plateau are known as the three polar regions of the Earth. As the most remote regions of the globe, the occurrence of persistent organic pollutants (POPs) in these polar regions arouses global concern. In this paper, we review the literatures on POPs involving these three polar regions. Overall, concentrations of POPs in the environment (air, water, soil and biota) have been extensively reported, with higher levels of dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) detected on the Tibetan Plateau. The spatial distribution of POPs in air, water and soil in the three polar regions broadly reflects their distances away from source regions. Based on long-term data, decreasing trends have been observed for most "legacy POPs". Observations of transport processes of POPs among multiple media have also been carried out, including air-water gas exchange, air-soil gas exchange, emissions from melting glaciers, bioaccumulations along food chains, and exposure risks. The impact of climate change on these processes possibly enhances the re-emission processes of POPs out of water, soil and glaciers, and reduces the bioaccumulation of POPs in food chains. Global POPs transport model have shown the Arctic receives a relatively small fraction of POPs, but that climate change will likely increase the total mass of all compounds in this polar region. Considering the impact of climate change on POPs is still unclear, long-term monitoring data and global/regional models are required, especially in the Antarctic and on the Tibetan Plateau, and the fate of POPs in all three polar regions needs to be comprehensively studied and compared to yield a better understanding of the mechanisms involved in the global cycling of POPs.
PubMed ID
30784838 View in PubMed
Less detail

Pharmaceuticals and personal care products (PPCPs) in Arctic environments: indicator contaminants for assessing local and remote anthropogenic sources in a pristine ecosystem in change.

https://arctichealth.org/en/permalink/ahliterature297653
Source
Environ Sci Pollut Res Int. 2018 Nov; 25(33):33001-33013
Publication Type
Journal Article
Review
Date
Nov-2018
Author
Roland Kallenborn
Eva Brorström-Lundén
Lars-Otto Reiersen
Simon Wilson
Author Affiliation
Faculty of Chemistry, Biotechnology and Food Sciences (KBM), Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway. roland.kallenborn@nmbu.no.
Source
Environ Sci Pollut Res Int. 2018 Nov; 25(33):33001-33013
Date
Nov-2018
Language
English
Publication Type
Journal Article
Review
Keywords
Animals
Arctic Regions
Biodegradation, Environmental
Cosmetics - analysis
Ecosystem
Ecotoxicology
Environment
Environmental Monitoring - methods
Food chain
Fresh Water - chemistry
Humans
Pharmaceutical Preparations - analysis
Seawater - chemistry
Sewage - chemistry
Waste Water
Water Pollutants, Chemical - analysis
Abstract
A first review on occurrence and distribution of pharmaceuticals and personal care products (PPCPs) is presented. The literature survey conducted here was initiated by the current Assessment of the Arctic Monitoring and Assessment Programme (AMAP). This first review on the occurrence and environmental profile of PPCPs in the Arctic identified the presence of 110 related substances in the Arctic environment based on the reports from scientific publications, national and regional assessments and surveys, as well as academic research studies (i.e., PhD theses). PPCP residues were reported in virtually all environmental compartments from coastal seawater to high trophic level biota. For Arctic environments, domestic and municipal wastes as well as sewage are identified as primary release sources. However, the absence of modern waste water treatment plants (WWTPs), even in larger settlements in the Arctic, is resulting in relatively high release rates for selected PPCPs into the receiving Arctic (mainly) aquatic environment. Pharmaceuticals are designed with specific biochemical functions as a part of an integrated therapeutically procedure. This biochemical effect may cause unwanted environmental toxicological effects on non-target organisms when the compound is released into the environment. In the Arctic environments, pharmaceutical residues are released into low to very low ambient temperatures mainly into aqueous environments. Low biodegradability and, thus, prolonged residence time must be expected for the majority of the pharmaceuticals entering the aquatic system. The environmental toxicological consequence of the continuous PPCP release is, thus, expected to be different in the Arctic compared to the temperate regions of the globe. Exposure risks for Arctic human populations due to consumption of contaminated local fish and invertebrates or through exposure to resistant microbial communities cannot be excluded. However, the scientific results reported and summarized here, published in 23 relevant papers and reports (see Table S1 and following references), must still be considered as indication only. Comprehensive environmental studies on the fate, environmental toxicology, and distribution profiles of pharmaceuticals applied in high volumes and released into the Nordic environment under cold Northern climate conditions should be given high priority by national and international authorities.
PubMed ID
28762048 View in PubMed
Less detail

Temporal trends of contaminants in Arctic human populations.

https://arctichealth.org/en/permalink/ahliterature297477
Source
Environ Sci Pollut Res Int. 2018 Oct; 25(29):28834-28850
Publication Type
Journal Article
Review
Date
Oct-2018
Author
Khaled Abass
Anastasia Emelyanova
Arja Rautio
Author Affiliation
Arctic Health, Faculty of Medicine, University of Oulu, P.O. Box 5000, FI-90014, Oulu, Finland. khaled.megahed@oulu.fi.
Source
Environ Sci Pollut Res Int. 2018 Oct; 25(29):28834-28850
Date
Oct-2018
Language
English
Publication Type
Journal Article
Review
Keywords
Arctic Regions
Child
Environmental Monitoring - methods
Environmental Pollutants - analysis - blood
Female
Food chain
Health status
Humans
Male
Milk, human - chemistry
Organic Chemicals - analysis - blood
Risk assessment
Russia
Spatio-Temporal Analysis
Abstract
The first Arctic Monitoring and Assessment Programme (AMAP) report was published in 1998 and followed by three assessment reports of human health (AMAP 2003, 2009 and 2015). The focus area of the AMAP reports was to monitor levels of environmental contaminants in the Arctic and to assess the health effects connected with detected levels in Arctic countries. This review gives an overview of temporal trends of contaminants and their health effects in humans of the Arctic based on data published by AMAP, as well as Russian scientific literature. Several time series of 31 contaminants in humans of the Arctic from different cohorts are reported. The lengths of time series and periods covered differ from each other. International restrictions have decreased the levels of most persistent organic pollutants in humans and food webs. Percentage changes for contaminants in human biological matrices (blood samples from children, mothers and males and breast milk samples) for the period of sampling showed declining trends in most of the monitored Arctic locations, with the exception of oxychlordane, hexachlorobenzene (HCB), 2,2',4,4',5,5'-hexabromodiphenyl ether (PBDE153) and perfluorinated compounds (PFCs).
PubMed ID
30145756 View in PubMed
Less detail

To Everything There Is a Season: Summer-to-Winter Food Webs and the Functional Traits of Keystone Species.

https://arctichealth.org/en/permalink/ahliterature292347
Source
Integr Comp Biol. 2017 11 01; 57(5):961-976
Publication Type
Journal Article
Review
Research Support, Non-U.S. Gov't
Date
11-01-2017
Author
Murray M Humphries
Emily K Studd
Allyson K Menzies
Stan Boutin
Author Affiliation
Department of Natural Resource Sciences, Macdonald Campus, McGill University, Ste-Anne-de-Bellevue, Québec, Canada H9X 3V9.
Source
Integr Comp Biol. 2017 11 01; 57(5):961-976
Date
11-01-2017
Language
English
Publication Type
Journal Article
Review
Research Support, Non-U.S. Gov't
Keywords
Animals
Ecosystem
Food chain
Hibernation
Mammals - physiology
Seasons
Abstract
From a trophic perspective, a seasonal increase in air temperature and photoperiod propagates as bottom-up pulse of primary production by plants, secondary production by herbivores, and tertiary production by carnivores. However, food web seasonality reflects not only abiotic variation in temperature and photoperiod, but also the composition of the biotic community and their functional responses to this variation. Some plants and animals-here referred to as seasonal specialists-decouple from food webs in winter through migration or various forms of metabolic arrest (e.g., senescence, diapause, and hibernation), whereas some plants and resident animals-here referred to as seasonal generalists-remain present and trophically coupled in winter. The co-occurrence of species with divergent responses to winter introduces seasonal variation in interaction strengths, resulting in summer-to-winter differences in trophic organization. Autumn cooling and shortening day length arrests primary productivity and cues seasonal herbivores to decouple, leaving generalist carnivores to concentrate their predation on the few generalist herbivores that remain resident, active, and vulnerable to predation in winter, which themselves feed on the few generalist plant structures available in winter. Thus, what was a bottom-up pulse, spread among many species in summer, including highly productive seasonal specialists, reverses into strong top-down regulation in winter that is top-heavy, and concentrated among a small number of generalist herbivores and their winter foods. Intermediate-sized, generalist herbivores that remain active and vulnerable to predation in winter are likely to be keystone species in seasonal food webs because they provide the essential ecosystem service of turning summer primary productivity into winter food for carnivores. Empirical examination of terrestrial mammals and their seasonal trophic status in the boreal forest and across an arctic-to-tropics seasonality gradient indicates seasonal specialization is more common among herbivores, small body sizes, and in regions with intermediate seasonality, than among carnivores, large body size, and regions where summers are very short or very long. Better understanding of food webs in seasonal environments, including their vulnerability and resilience to climate change, requires a multi-season perspective.
PubMed ID
29040576 View in PubMed
Less detail

Using experimentation to understand the 10-year snowshoe hare cycle in the boreal forest of North America.

https://arctichealth.org/en/permalink/ahliterature292624
Source
J Anim Ecol. 2018 Jan; 87(1):87-100
Publication Type
Journal Article
Review
Date
Jan-2018
Author
Charles J Krebs
Rudy Boonstra
Stan Boutin
Author Affiliation
Department of Zoology, University of British Columbia, Vancouver, BC, Canada.
Source
J Anim Ecol. 2018 Jan; 87(1):87-100
Date
Jan-2018
Language
English
Publication Type
Journal Article
Review
Keywords
Alaska
Animals
Canada
Food chain
Hares - physiology
Lynx - physiology
Population Dynamics
Predatory Behavior
Reproduction
Seasons
Taiga
Time Factors
Abstract
Population cycles have long fascinated ecologists from the time of Charles Elton in the 1920s. The discovery of large population fluctuations in undisturbed ecosystems challenged the idea that pristine nature was in a state of balance. The 10-year cycle of snowshoe hares (Lepus americanus Erxleben) across the boreal forests of Canada and Alaska is a classic cycle, recognized by fur traders for more than 300 years. Since the 1930s, ecologists have investigated the mechanisms that might cause these cycles. Proposed causal mechanisms have varied from sunspots to food supplies, parasites, diseases, predation and social behaviour. Both the birth rate and the death rate change dramatically over the cycle. Social behaviour was eliminated as a possible cause because snowshoe hares are not territorial and do not commit infanticide. Since the 1960s, large-scale manipulative experiments have been used to discover the major limiting factors. Food supply and predation quickly became recognized as potential key factors causing the cycle. Experiments adding food and restricting predator access to field populations have been decisive in pinpointing predation as the key mechanism causing these fluctuations. The immediate cause of death of most snowshoe hares is predation by a variety of predators, including the Canada lynx (Lynx canadensis Kerr). The collapse in the reproductive rate is not due to food shortage as was originally thought, but is a result of chronic stress from predator chases. Five major issues remain unresolved. First, what is the nature of the predator-induced memory that results in the prolonged low phase of the cycle? Second, why do hare cycles form a travelling wave, starting in the centre of the boreal forest in Saskatchewan and travelling across western Canada and Alaska? Third, why does the amplitude of the cycle vary greatly from one cycle to the next in the same area? Fourth, do the same mechanisms of population limitation apply to snowshoe hares in eastern North American or in similar ecosystems across Siberia? Finally, what effect will climatic warming have on all the above issues? The answers to these questions remain for future generations of biologists to determine.
PubMed ID
28636751 View in PubMed
Less detail

6 records – page 1 of 1.