Are liver and renal lesions in East Greenland polar bears ( Ursus maritimus ) associated with high mercury levels?
Abstract Background In the Arctic, polar bears ( Ursus maritimus ) bio-accumulate mercury as they prey on polluted ringed seals ( Phoca hispida ) and bearded seals ( Erignathus barbatus ). Studies have shown that polar bears from East Greenland are among the most mercury polluted species in the Arct...
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ftdoajarticles:oai:doaj.org/article:3dbce4672666451c9ec200b78b4aa279 2023-05-15T14:52:04+02:00 Are liver and renal lesions in East Greenland polar bears ( Ursus maritimus ) associated with high mercury levels? Born Erik W Kirkegaard Maja Asmund Gert Leifsson Pall S Dietz Rune Sonne Christian 2007-04-01T00:00:00Z https://doi.org/10.1186/1476-069X-6-11 https://doaj.org/article/3dbce4672666451c9ec200b78b4aa279 EN eng BMC http://www.ehjournal.net/content/6/1/11 https://doaj.org/toc/1476-069X doi:10.1186/1476-069X-6-11 1476-069X https://doaj.org/article/3dbce4672666451c9ec200b78b4aa279 Environmental Health, Vol 6, Iss 1, p 11 (2007) Industrial medicine. Industrial hygiene RC963-969 Public aspects of medicine RA1-1270 article 2007 ftdoajarticles https://doi.org/10.1186/1476-069X-6-11 2022-12-30T21:45:34Z Abstract Background In the Arctic, polar bears ( Ursus maritimus ) bio-accumulate mercury as they prey on polluted ringed seals ( Phoca hispida ) and bearded seals ( Erignathus barbatus ). Studies have shown that polar bears from East Greenland are among the most mercury polluted species in the Arctic. It is unknown whether these levels are toxic to liver and kidney tissue. Methods We investigated the histopathological impact from anthropogenic long-range transported mercury on East Greenland polar bear liver (n = 59) and kidney (n = 57) tissues. Results Liver mercury levels ranged from 1.1–35.6 μg/g wet weight and renal levels ranged from 1–50 μg/g wet weight, of which 2 liver values and 9 kidney values were above known toxic threshold level of 30 μg/g wet weight in terrestrial mammals. Evaluated from age-correcting ANCOVA analyses, liver mercury levels were significantly higher in individuals with visible Ito cells (p < 0.02) and a similar trend was found for lipid granulomas (p = 0.07). Liver mercury levels were significantly lower in individuals with portal bile duct proliferation/fibrosis (p = 0.007) and a similar trend was found for proximal convoluted tubular hyalinisation in renal tissue (p = 0.07). Conclusion Based on these relationships and the nature of the chronic inflammation we conclude that the lesions were likely a result of recurrent infections and ageing but that long-term exposure to mercury could not be excluded as a co-factor. The information is important as it is likely that tropospheric mercury depletion events will continue to increase the concentrations of this toxic heavy metal in the Sub Arctic and Arctic marine food webs. Article in Journal/Newspaper Arctic East Greenland Erignathus barbatus Greenland Phoca hispida Ursus maritimus Directory of Open Access Journals: DOAJ Articles Arctic Greenland Environmental Health 6 1 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
language |
English |
topic |
Industrial medicine. Industrial hygiene RC963-969 Public aspects of medicine RA1-1270 |
spellingShingle |
Industrial medicine. Industrial hygiene RC963-969 Public aspects of medicine RA1-1270 Born Erik W Kirkegaard Maja Asmund Gert Leifsson Pall S Dietz Rune Sonne Christian Are liver and renal lesions in East Greenland polar bears ( Ursus maritimus ) associated with high mercury levels? |
topic_facet |
Industrial medicine. Industrial hygiene RC963-969 Public aspects of medicine RA1-1270 |
description |
Abstract Background In the Arctic, polar bears ( Ursus maritimus ) bio-accumulate mercury as they prey on polluted ringed seals ( Phoca hispida ) and bearded seals ( Erignathus barbatus ). Studies have shown that polar bears from East Greenland are among the most mercury polluted species in the Arctic. It is unknown whether these levels are toxic to liver and kidney tissue. Methods We investigated the histopathological impact from anthropogenic long-range transported mercury on East Greenland polar bear liver (n = 59) and kidney (n = 57) tissues. Results Liver mercury levels ranged from 1.1–35.6 μg/g wet weight and renal levels ranged from 1–50 μg/g wet weight, of which 2 liver values and 9 kidney values were above known toxic threshold level of 30 μg/g wet weight in terrestrial mammals. Evaluated from age-correcting ANCOVA analyses, liver mercury levels were significantly higher in individuals with visible Ito cells (p < 0.02) and a similar trend was found for lipid granulomas (p = 0.07). Liver mercury levels were significantly lower in individuals with portal bile duct proliferation/fibrosis (p = 0.007) and a similar trend was found for proximal convoluted tubular hyalinisation in renal tissue (p = 0.07). Conclusion Based on these relationships and the nature of the chronic inflammation we conclude that the lesions were likely a result of recurrent infections and ageing but that long-term exposure to mercury could not be excluded as a co-factor. The information is important as it is likely that tropospheric mercury depletion events will continue to increase the concentrations of this toxic heavy metal in the Sub Arctic and Arctic marine food webs. |
format |
Article in Journal/Newspaper |
author |
Born Erik W Kirkegaard Maja Asmund Gert Leifsson Pall S Dietz Rune Sonne Christian |
author_facet |
Born Erik W Kirkegaard Maja Asmund Gert Leifsson Pall S Dietz Rune Sonne Christian |
author_sort |
Born Erik W |
title |
Are liver and renal lesions in East Greenland polar bears ( Ursus maritimus ) associated with high mercury levels? |
title_short |
Are liver and renal lesions in East Greenland polar bears ( Ursus maritimus ) associated with high mercury levels? |
title_full |
Are liver and renal lesions in East Greenland polar bears ( Ursus maritimus ) associated with high mercury levels? |
title_fullStr |
Are liver and renal lesions in East Greenland polar bears ( Ursus maritimus ) associated with high mercury levels? |
title_full_unstemmed |
Are liver and renal lesions in East Greenland polar bears ( Ursus maritimus ) associated with high mercury levels? |
title_sort |
are liver and renal lesions in east greenland polar bears ( ursus maritimus ) associated with high mercury levels? |
publisher |
BMC |
publishDate |
2007 |
url |
https://doi.org/10.1186/1476-069X-6-11 https://doaj.org/article/3dbce4672666451c9ec200b78b4aa279 |
geographic |
Arctic Greenland |
geographic_facet |
Arctic Greenland |
genre |
Arctic East Greenland Erignathus barbatus Greenland Phoca hispida Ursus maritimus |
genre_facet |
Arctic East Greenland Erignathus barbatus Greenland Phoca hispida Ursus maritimus |
op_source |
Environmental Health, Vol 6, Iss 1, p 11 (2007) |
op_relation |
http://www.ehjournal.net/content/6/1/11 https://doaj.org/toc/1476-069X doi:10.1186/1476-069X-6-11 1476-069X https://doaj.org/article/3dbce4672666451c9ec200b78b4aa279 |
op_doi |
https://doi.org/10.1186/1476-069X-6-11 |
container_title |
Environmental Health |
container_volume |
6 |
container_issue |
1 |
_version_ |
1766323185256497152 |