Profiles of seven compounds of perfluoro-alkyl substances (PFASs) were compared among three species of top predators from the Danish North Sea: the white-beaked dolphin (
Lagenorhynchus albirostris
...), the harbor porpoise (
Phocoena phocoena
), and the harbor seal (
Phoca vitulina
). The seals had higher total burdens (757.8 ng g
−1
ww) than the dolphins (439.9 ng g
−1
ww) and the porpoises (355.8 ng g
−1
ww), probably a reflection of feeding closer to the shore and thus contamination sources. The most striking difference among the species was the relative contribution of perfluorooctanesulfonamide (PFOSA) to the profiles; the seals (0.1 %) had much lower levels than porpoises (8.3 %) and dolphins (26.0 %). In combination with the values obtained from the literature, this result indicates that Carnivora species including Pinnipedia have a much higher capacity of transforming PFOSA to perfluorooctane sulfonic acid (PFOS) than cetacean species. Another notable difference among the species was that the two smaller species (seals and porpoises) with supposedly higher metabolic rates had lower concentrations of the perfluorinated carboxylic acids, which are generally more easily excreted than perfluorinated sulfonamides. Species-specific characteristics should be recognized when PFAS contamination in marine mammals is investigated, for example, several previous studies of PFASs in cetaceans have not quantified PFOSA.
Indoor radon survey in Greenland and dose assessment Hansen, Violeta; Petersen, Dorthe; Søgaard-Hansen, Jens ...
Journal of environmental radioactivity,
February 2023, 2023-Feb, 2023-02-00, Letnik:
257
Journal Article
Recenzirano
Odprti dostop
Indoor radon and its decay products are the primary sources of the population's exposure to background ionizing radiation. Radon decay products are one of the leading causes of lung cancer, with a ...higher lung cancer risk for smokers due to the synergistic effects of radon decay products and cigarette smoking. A total of 459 year-long radon measurements in 257 detached and semi-detached residential homes in southwest and south Greenland were carried out, and a dose assessment for adults was performed. The annual arithmetic and geometric means of indoor radon concentrations was 10.5 ± 0.2 Bq m−3 and 8.0 ± 2.3 Bq m−3 in Nuuk, 139.0 ± 1.0 Bq m−3 and 97.3 ± 2.1 Bq m−3 in Narsaq, and 42.1 ± 0.7 Bq m−3 and 22.0 ± 3.1 Bq m−3 in Qaqortoq. Arithmetic and geometric mean radon concentration of 79.0 Bq m−3 and 50.3 Bq m−3 were estimated for adult, person-weighted living in south Greenland. The total number of detached and semi-detached residential homes where indoor radon is exceeding 100 Bq m−3, 200 Bq m−3, and 300 Bq m−3 is 37 homes (15.0%), 13 homes (5.2%), and 8 homes (3.2%), respectively. A positive correlation between indoor air radon concentrations and underlying geology was observed.
The indoor radon contribution to the annual inhalation effective dose to an average adult was 0.5 mSv in Nuuk, 6.5 mSv in Narsaq, 2.0 mSv in Qaqortoq, and 4.0 mSv for south Greenland adult person weighted. The estimated annual average effective dose to adults in Narsaq is higher than the world's average annual effective dose of 1.3 mSv due to inhalation of indoor radon. Cost-efficient mitigation methods exist to reduce radon in existing buildings, and to prevent radon entry into new buildings.
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•Indoor radon concentrations varied significantly between studied towns.•Positive correlation between indoor radon concentrations and underlying geology.•Positive correlation between indoor radon and house metrics in some towns.•Sporadic permafrost in Nuuk town, may suppress radon emanation.•Annual average effective dose to adults in Narsaq is higher than world annual dose.
Radon-222 (
Rn) and its decay products are the primary sources of a population's exposure to background ionizing radiation. Radon decay products are the leading cause of lung cancer for non-smokers ...and the second leading cause of lung cancer after smoking for smokers. A community-driven long-term radon survey was completed in 232 residential homes in different subdivisions of Whitehorse, the capital of the Yukon, during the heating season from November to April in 2016-2017 and in 2017-2018. Radon concentrations were measured in living rooms and bedrooms on ground floors. The arithmetic and geometric means of indoor radon activity concentrations in different subdivisions of Whitehorse ranged from 52 ± 0.6 Bq m
and 37 ± 2.3 Bq m
in the Downtown area of Whitehorse to 993.0 ± 55.0 Bq m
and 726.2 ± 2.4 Bq m
in Wolf Creek. Underlying geology and glacial surfaces may partly explain these variations of indoor radon concentrations in subdivisions of Whitehorse. A total of 78 homes (34.0%) had radon concentrations higher than 100 Bq m
, 47 homes (20.5%) had concentrations higher than 200 Bq m
and 33 homes (14.4%) had concentrations higher than 300 Bq m
. The indoor radon contribution to the annual effective inhalation dose to residents ranged from 3.0 mSv in the Downtown area to 51.0 mSv in Wolf Creek. The estimated annual average dose to adults in Whitehorse, Yukon, is higher than the world's average annual effective dose of 1.3 mSv due to the inhalation of indoor radon. The annual radon inhalation effective dose was assessed using radon measurements taken during winter; hence the assessed dose may be overestimated. Cost-efficient mitigation methods are available to reduce radon in existing buildings and to prevent radon entry into new buildings.
Polonium-210 (210Po) is a radionuclide sentinel as it bioaccumulates in marine organisms, thereby being the main contributor to committed dietary doses in seafood consumers. Although seafood and ...marine mammals are an important part of the traditional Inuit diet, there is a general lack of information on the 210Po concentrations in the Greenlandic marine food chain leading to the human consumer. Here, we determine background 210Po concentrations in edible parts of different marine organisms from Greenland and provide a dose assessment. Blue mussels (Mytilus edulis), organs of ringed seal (Pusa hispida) and polar bear (Ursus maritimus) displayed significantly elevated 210Po concentrations in respect to all other studied organisms (p < 0.001). 210Po concentrations ranged from 0.02 Bq kg-1, w.w. in Greenland halibut (Reinhardtius hippoglossoides) muscle to 78 Bq kg-1, w.w. and 202 Bq kg-1, w.w. in ringed seal muscle and kidneys, respectively. 210Po concentration ratio for edible parts increases in the order bladderwrack (Fucus Vesiculosus), northern shrimp (Pandalus borealis), blue mussels, and from fish species to ringed seal and polar bear. 210Po distribution in fish, ringed seal, and polar bear follows a general pattern, the lowest concentrations were in muscle, and the highest concentrations were in the organs involved in metabolism. The derived 210Po annual absorbed dose in edible parts of studied marine organisms are several orders of magnitude lower than the recommended dose rate screening value of 10 μGy h-1. Effective doses from intake of 210Po to Greenland average children (1.4 mSv y-1), and high seafood and marine mammal consumers (2 mSv y-1 for adults and 3.6 mSv y-1 for children) are higher than the world average annual effective dose due to ingestion of naturally occurring radionuclides.
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•Large inter-specific variability of 210Po concentrations in marine organisms•First 210Po study in polar bears from Arctic regions•210Po is non-uniformly distributed in the body of the marine organisms.•210Po annual absorbed doses in the marine organisms are low.•Exposure to 210Po was significant to children and the most exposed persons.
Climate change will increasingly affect the natural habitat and diet of polar bears (Ursus maritimus). Understanding the energetic needs of polar bears is therefore important. We developed a ...theoretical method for estimating polar bear food consumption based on using the highly recalcitrant polychlorinated biphenyl (PCB) congener, 2,2',4,4',55-hexaCB (CB153) in bear adipose tissue as an indicator of food intake. By comparing the CB153 tissue concentrations in wild polar bears with estimates from a purposely designed individual-based model, we identified the possible combinations of field metabolic rates (FMR) and CB153 deposition efficiencies in East Greenland polar bears. Our simulations indicate that if 30% of the CB153 consumed by polar bear individuals were deposited into their adipose tissue, the corresponding FMR would be only two times the basal metabolic rate. In contrast, if the modelled CB153 deposition efficiency were 10%, adult polar bears would require six times more energy than that needed to cover basal metabolism. This is considerably higher than what has been assumed for polar bears in previous studies though it is similar to FMRs found in other marine mammals. An implication of this result is that even relatively small reductions in future feeding opportunities could impact the survival of East Greenland polar bears.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
The Earth's polar regions are low rates of inter‐ and intraspecific diversification. An extreme mammalian example is the Arctic ringed seal (
Pusa hispida hispida
), which is assumed to be ...panmictic across its circumpolar Arctic range. Yet, local Inuit communities in Greenland and Canada recognize several regional variants; a finding supported by scientific studies of body size variation. It is however unclear whether this phenotypic variation reflects plasticity, morphs or distinct ecotypes. Here, we combine genomic, biologging and survey data, to document the existence of a unique ringed seal ecotype in the Ilulissat Icefjord (locally ‘Kangia’), Greenland; a UNESCO World Heritage site, which is home to the most productive marine‐terminating glacier in the Arctic. Genomic analyses reveal a divergence of Kangia ringed seals from other Arctic ringed seals about 240 kya, followed by secondary contact since the Last Glacial Maximum. Despite ongoing gene flow, multiple genomic regions appear under strong selection in Kangia ringed seals, including candidate genes associated with pelage coloration, growth and osmoregulation, potentially explaining the Kangia seal's phenotypic and behavioural uniqueness. The description of ‘hidden’ diversity and adaptations in yet another Arctic species merits a reassessment of the evolutionary processes that have shaped Arctic diversity and the traditional view of this region as an evolutionary freezer. Our study highlights the value of indigenous knowledge in guiding science and calls for efforts to identify distinct populations or ecotypes to understand how these might respond differently to environmental change.
Contaminants of emerging concern receive increasing attention in the Arctic environment. The aim of this study was to screen for chemicals of emerging Arctic concern (CEACs) in different types of ...Arctic samples including biota, air and human serum. We used a combination of gas chromatography (GC) and liquid chromatography (LC) with high resolution mass spectrometry (HRMS) for suspect and non-target screening (NTS). Suspect screening of 25 CEACs was based on published in-silico approaches for the identification of CEACs and revealed tetrabromophthalic anhydride (TBPA) in pilot whale and air, albeit with low detection frequencies (17 and 33%, respectively). An NTS workflow detected a total of 112 contaminants, i.e. 49, 42, 31 and 30 compounds in pilot whale, ringed seal, air, and human serum respectively at confidence level 2 and 3. Although legacy POPs still dominated the samples, 64 CEACs were tentatively identified and further tentatively assessed for persistence (P), bioaccumulation (B), mobility (M), toxicity (T), and long-range transport potential (LRTP). While four PBT compounds were identified, 37 PMT substances dominated among these 64 contaminants. Our study indicated that many chemicals of potential risk might be present in Arctic samples that would benefit from confirmation and further studies of their transport to and accumulation in the Arctic environment.
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•Non-target and suspect screening were applied to Arctic air, biota and human serum.•Suspect screening identified tetrabromophthalic anhydride in air and pilot whales.•64 chemicals of emerging Arctic concern (CEACs) were tentatively identified.•Some CEACs had not been reported from the Arctic before and warrant confirmation.•Preliminary risk assessment indicated PBT and PMT characteristics for most CEACs.
Naturally occurring radionuclides, in particular, polonium-210 (210Po), have a greater contribution than anthropogenic radionuclides to the annual effective dose received by the general public due to ...consumption of seafood. Knowledge of potential trophic sources and transfer of 210Po to seabird species and subsequently to the Greenlandic people is, however, still poor. Here, we assess the transfer of 210Po and 210Pb to seabirds sampled during autumn and winter 2017 and 2018 in Greenland and provide a dose assessment. The activity concentrations of 210Po in muscle and liver, respectively, ranged from 0.2 ± 0.1 Bq kg−1 w.w. in glaucous gull (Larus hyperboreus) to 21.2 ± 22.6 Bq kg−1 w.w. in thick-billed murre (Uria lomvia) and from 32.0 ± 9.4 Bq kg−1 w.w. in common eider (Somateria mollissima) to 40.5 ± 49.0 Bq kg−1 w.w. in thick-billed murre. 210Po was non-uniformly distributed in the body of thick-billed murre. Kidneys and feathers showed higher 210Po activity concentrations than heart and bone. The 210Po/210Pb activity concentration ratios are higher than unity, indicating that 210Po is preferentially taken up by seabirds compared to its progenitor 210Pb. The derived annual absorbed dose from 210Po to the whole body of thick-billed murre was 6.4 × 102 ± 3.0 × 102 μGy. The annual effective dose to the average adult and representative person in Greenland due to ingestion of 210Po in seabirds was estimated to 13.0 μSv and 57.0 μSv, respectively. This derived dose is low and poses a slight risk, and risk communication is therefore deemed unnecessary.
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•Large inter-specific variability of 210Po concentrations in seabirds.•Species feeding at lower trophic positions show higher 210Po concentrations than species feeding at high trophic positions.•210Po is non-uniformly distributed in the soft tissues and feathers of birds.•Derived annual absorbed dose due to 210Po to the whole body of thick-billed murre was low.•The annual effective dose due to ingestion of 210Po to average adult and representative person in Greenland is low.
Atlantic walruses (Odobenus rosmarus rosmarus) belonging to the Baffin Bay subpopulation occur year round in the North Water polynya (NOW) between NW Greenland and eastern Ellesmere Island (Canada). ...They are hunted for subsistence purposes by residents of the Qaanaaq area (NW Greenland) bordering the NOW to the east and by Canadian Inuit at the entrance to Jones Sound in Nunavut. During the open-water period NW Greenland is virtually devoid of walruses which concentrate along eastern and southern Ellesmere Island at this time of the year. To determine the abundance of walruses in the NOW area, aerial surveys were conducted in August of 1999, 2008, and 2009. In July 2009, nine satellite-linked transmitters were deployed in nearby Kane Basin. Surveys on 9 and 20 August 2009 along eastern Ellesmere Island were the most extensive and were augmented with concomitant data on haul-out and at water surface activity from three (1 F, 2 M) of the nine tags that were still functioning. We therefore focus on the 2009 surveys. Walruses were observed on the ice and in water primarily in Buchanan Bay and Princess Marie Bay where the remaining functional tags were located. The Minimum Counted population (MCP) was 571 on 20 August. Adjusting the MCP of walruses on ice for those not hauled out, the estimate of abundance of walruses in the Baffin Bay stock was 1,251(CV=1.00, 95% CI = 1,226) when adjusted by the proportion of tags ‘dry’ at the time of the survey and 1,249 (CV=1.12, 95% CI = 1,370) when adjusted by the average time tags were dry. The surveys did not cover all potential walrus summering habitat along eastern Ellesmere Island and are negatively biased to an unknown degree.
Naturally occurring radionuclides, in particular, polonium-210 (
Po), have a greater contribution than anthropogenic radionuclides to the annual effective dose received by the general public due to ...consumption of seafood. Knowledge of potential trophic sources and transfer of
Po to seabird species and subsequently to the Greenlandic people is, however, still poor. Here, we assess the transfer of
Po and
Pb to seabirds sampled during autumn and winter 2017 and 2018 in Greenland and provide a dose assessment. The activity concentrations of
Po in muscle and liver, respectively, ranged from 0.2 ± 0.1 Bq kg
w.w. in glaucous gull (Larus hyperboreus) to 21.2 ± 22.6 Bq kg
w.w. in thick-billed murre (Uria lomvia) and from 32.0 ± 9.4 Bq kg
w.w. in common eider (Somateria mollissima) to 40.5 ± 49.0 Bq kg
w.w. in thick-billed murre.
Po was non-uniformly distributed in the body of thick-billed murre. Kidneys and feathers showed higher
Po activity concentrations than heart and bone. The
Po/
Pb activity concentration ratios are higher than unity, indicating that
Po is preferentially taken up by seabirds compared to its progenitor
Pb. The derived annual absorbed dose from
Po to the whole body of thick-billed murre was 6.4 × 10
± 3.0 × 10
μGy. The annual effective dose to the average adult and representative person in Greenland due to ingestion of
Po in seabirds was estimated to 13.0 μSv and 57.0 μSv, respectively. This derived dose is low and poses a slight risk, and risk communication is therefore deemed unnecessary.
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