Climate change and overfishing increase neurotoxicant in marine predators
More than three billion people rely on seafood for nutrition. However, fish are the predominant source of human exposure to methylmercury (MeHg), a potent neurotoxic substance. In the United States, 82% of population-wide exposure to MeHg is from the consumption of marine seafood and almost 40% is f...
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ftiith:oai:raiith.iith.ac.in:5921 2023-05-15T15:27:50+02:00 Climate change and overfishing increase neurotoxicant in marine predators Schartup, Amina T Thackray, Colin P Qureshi, Asif 2019 http://raiith.iith.ac.in/5921/ https://doi.org/10.1038/s41586-019-1468-9 unknown Schartup, Amina T and Thackray, Colin P and Qureshi, Asif (2019) Climate change and overfishing increase neurotoxicant in marine predators. Nature. ISSN 0028-0836 Civil Engineering Article PeerReviewed 2019 ftiith https://doi.org/10.1038/s41586-019-1468-9 2022-09-28T08:35:32Z More than three billion people rely on seafood for nutrition. However, fish are the predominant source of human exposure to methylmercury (MeHg), a potent neurotoxic substance. In the United States, 82% of population-wide exposure to MeHg is from the consumption of marine seafood and almost 40% is from fresh and canned tuna alone1. Around 80% of the inorganic mercury (Hg) that is emitted to the atmosphere from natural and human sources is deposited in the ocean2, where some is converted by microorganisms to MeHg. In predatory fish, environmental MeHg concentrations are amplified by a million times or more. Human exposure to MeHg has been associated with long-term neurocognitive deficits in children that persist into adulthood, with global costs to society that exceed US$20 billion3. The first global treaty on reductions in anthropogenic Hg emissions (the Minamata Convention on Mercury) entered into force in 2017. However, effects of ongoing changes in marine ecosystems on bioaccumulation of MeHg in marine predators that are frequently consumed by humans (for example, tuna, cod and swordfish) have not been considered when setting global policy targets. Here we use more than 30 years of data and ecosystem modelling to show that MeHg concentrations in Atlantic cod (Gadus morhua) increased by up to 23% between the 1970s and 2000s as a result of dietary shifts initiated by overfishing. Our model also predicts an estimated 56% increase in tissue MeHg concentrations in Atlantic bluefin tuna (Thunnus thynnus) due to increases in seawater temperature between a low point in 1969 and recent peak levels—which is consistent with 2017 observations. This estimated increase in tissue MeHg exceeds the modelled 22% reduction that was achieved in the late 1990s and 2000s as a result of decreased seawater MeHg concentrations. The recently reported plateau in global anthropogenic Hg emissions4 suggests that ocean warming and fisheries management programmes will be major drivers of future MeHg concentrations in marine predators. Article in Journal/Newspaper atlantic cod Gadus morhua Research Archive of Indian Institute of Technology, Hyderabad (RAIITH) Low Point ENVELOPE(-37.183,-37.183,-54.050,-54.050) Nature 572 7771 648 650 |
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Research Archive of Indian Institute of Technology, Hyderabad (RAIITH) |
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language |
unknown |
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Civil Engineering |
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Civil Engineering Schartup, Amina T Thackray, Colin P Qureshi, Asif Climate change and overfishing increase neurotoxicant in marine predators |
topic_facet |
Civil Engineering |
description |
More than three billion people rely on seafood for nutrition. However, fish are the predominant source of human exposure to methylmercury (MeHg), a potent neurotoxic substance. In the United States, 82% of population-wide exposure to MeHg is from the consumption of marine seafood and almost 40% is from fresh and canned tuna alone1. Around 80% of the inorganic mercury (Hg) that is emitted to the atmosphere from natural and human sources is deposited in the ocean2, where some is converted by microorganisms to MeHg. In predatory fish, environmental MeHg concentrations are amplified by a million times or more. Human exposure to MeHg has been associated with long-term neurocognitive deficits in children that persist into adulthood, with global costs to society that exceed US$20 billion3. The first global treaty on reductions in anthropogenic Hg emissions (the Minamata Convention on Mercury) entered into force in 2017. However, effects of ongoing changes in marine ecosystems on bioaccumulation of MeHg in marine predators that are frequently consumed by humans (for example, tuna, cod and swordfish) have not been considered when setting global policy targets. Here we use more than 30 years of data and ecosystem modelling to show that MeHg concentrations in Atlantic cod (Gadus morhua) increased by up to 23% between the 1970s and 2000s as a result of dietary shifts initiated by overfishing. Our model also predicts an estimated 56% increase in tissue MeHg concentrations in Atlantic bluefin tuna (Thunnus thynnus) due to increases in seawater temperature between a low point in 1969 and recent peak levels—which is consistent with 2017 observations. This estimated increase in tissue MeHg exceeds the modelled 22% reduction that was achieved in the late 1990s and 2000s as a result of decreased seawater MeHg concentrations. The recently reported plateau in global anthropogenic Hg emissions4 suggests that ocean warming and fisheries management programmes will be major drivers of future MeHg concentrations in marine predators. |
format |
Article in Journal/Newspaper |
author |
Schartup, Amina T Thackray, Colin P Qureshi, Asif |
author_facet |
Schartup, Amina T Thackray, Colin P Qureshi, Asif |
author_sort |
Schartup, Amina T |
title |
Climate change and overfishing increase neurotoxicant in marine predators |
title_short |
Climate change and overfishing increase neurotoxicant in marine predators |
title_full |
Climate change and overfishing increase neurotoxicant in marine predators |
title_fullStr |
Climate change and overfishing increase neurotoxicant in marine predators |
title_full_unstemmed |
Climate change and overfishing increase neurotoxicant in marine predators |
title_sort |
climate change and overfishing increase neurotoxicant in marine predators |
publishDate |
2019 |
url |
http://raiith.iith.ac.in/5921/ https://doi.org/10.1038/s41586-019-1468-9 |
long_lat |
ENVELOPE(-37.183,-37.183,-54.050,-54.050) |
geographic |
Low Point |
geographic_facet |
Low Point |
genre |
atlantic cod Gadus morhua |
genre_facet |
atlantic cod Gadus morhua |
op_relation |
Schartup, Amina T and Thackray, Colin P and Qureshi, Asif (2019) Climate change and overfishing increase neurotoxicant in marine predators. Nature. ISSN 0028-0836 |
op_doi |
https://doi.org/10.1038/s41586-019-1468-9 |
container_title |
Nature |
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572 |
container_issue |
7771 |
container_start_page |
648 |
op_container_end_page |
650 |
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1766358235206385664 |