Spatial variability and depuration of tetrodotoxin in the bivalve Paphies australis from New Zealand
Tetrodotoxin (TTX) is a potent neurotoxin responsible for many human intoxications globally. Despite its potency and widespread occurrence in taxonomically diverse species, the primary source of TTX remains uncertain. Paphies australis, an endemic clam found in New Zealand, has been found to contain...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2019-04-01
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| Series: | Toxicon: X |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2590171019300050 |
| _version_ | 1818241276580986880 |
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| author | Laura Biessy Kirsty F. Smith D. Tim Harwood Michael J. Boundy Ian Hawes Susanna A. Wood |
| author_facet | Laura Biessy Kirsty F. Smith D. Tim Harwood Michael J. Boundy Ian Hawes Susanna A. Wood |
| author_sort | Laura Biessy |
| collection | DOAJ |
| description | Tetrodotoxin (TTX) is a potent neurotoxin responsible for many human intoxications globally. Despite its potency and widespread occurrence in taxonomically diverse species, the primary source of TTX remains uncertain. Paphies australis, an endemic clam found in New Zealand, has been found to contain TTX in several locations. However, it is unknown if this represents endogenous production or accumulation from an external source. To address this question, the concentrations of TTX in whole P. australis and dissected organs (siphons, foot, digestive gland and the ‘rest’) from thirteen sites around New Zealand were determined using liquid chromatography-tandem quadrupole mass spectrometry analysis (LC-MS/MS). Depuration rate of TTX was also investigated by harvesting and measuring concentrations in P. australis maintained in captivity on a toxin-free diet every three to 15 days for 150 days. The LC-MS/MS analyses of the spatial samples showed that TTX was present in P. australis from all regions tested, with significantly (p < 0.001) higher concentrations (15–50 μg kg−1) observed at lower latitudes of the North Island compared with trace levels (0.5–3 μg kg−1) in the South Island of New Zealand. Tetrodotoxin was detected in all the dissected organs but the siphons contained the highest concentrations of TTX at all sites analysed. A linear model of the depuration data identified a significant (p < 0.001) decline in total TTX concentrations in P. australis over the study period. The siphons maintained the highest amount of TTX across the entire depuration study. The digestive glands contained low concentrations at the start of the experiment, but this depurated rapidly and only traces remained after 21 days. These results provide evidence to suggest that P. australis does not produce TTX endogenously but obtains the neurotoxin from an exogenous source (e.g., diet) with the source more prevalent in warmer northern waters. The association of higher TTX concentrations in shellfish with warmer environments raises concerns that this toxin's distribution and abundance could become an increasing human health issue with global warming. Keywords: Biotoxin, Clam, Emerging threat, Geographic variability, Marine bivalves, Neurotoxin |
| first_indexed | 2024-12-12T13:26:46Z |
| format | Article |
| id | doaj.art-f5825570404043f9aa944dbe16832988 |
| institution | Directory Open Access Journal |
| issn | 2590-1710 |
| language | English |
| last_indexed | 2024-12-12T13:26:46Z |
| publishDate | 2019-04-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Toxicon: X |
| spelling | doaj.art-f5825570404043f9aa944dbe168329882022-12-22T00:23:10ZengElsevierToxicon: X2590-17102019-04-012Spatial variability and depuration of tetrodotoxin in the bivalve Paphies australis from New ZealandLaura Biessy0Kirsty F. Smith1D. Tim Harwood2Michael J. Boundy3Ian Hawes4Susanna A. Wood5Cawthron Institute, Private Bag 2, Nelson, 7010, New Zealand; Department of Biological Sciences, University of Waikato, Private Bag 3105, Hamilton, 3240, New Zealand; New Zealand Food Safety Science & Research Centre, Palmerston North, 4442, New Zealand; Corresponding author. Cawthron Institute, Private Bag 2, Nelson, 7010, New Zealand.Cawthron Institute, Private Bag 2, Nelson, 7010, New ZealandCawthron Institute, Private Bag 2, Nelson, 7010, New Zealand; New Zealand Food Safety Science & Research Centre, Palmerston North, 4442, New ZealandCawthron Institute, Private Bag 2, Nelson, 7010, New ZealandDepartment of Biological Sciences, University of Waikato, Private Bag 3105, Hamilton, 3240, New ZealandCawthron Institute, Private Bag 2, Nelson, 7010, New ZealandTetrodotoxin (TTX) is a potent neurotoxin responsible for many human intoxications globally. Despite its potency and widespread occurrence in taxonomically diverse species, the primary source of TTX remains uncertain. Paphies australis, an endemic clam found in New Zealand, has been found to contain TTX in several locations. However, it is unknown if this represents endogenous production or accumulation from an external source. To address this question, the concentrations of TTX in whole P. australis and dissected organs (siphons, foot, digestive gland and the ‘rest’) from thirteen sites around New Zealand were determined using liquid chromatography-tandem quadrupole mass spectrometry analysis (LC-MS/MS). Depuration rate of TTX was also investigated by harvesting and measuring concentrations in P. australis maintained in captivity on a toxin-free diet every three to 15 days for 150 days. The LC-MS/MS analyses of the spatial samples showed that TTX was present in P. australis from all regions tested, with significantly (p < 0.001) higher concentrations (15–50 μg kg−1) observed at lower latitudes of the North Island compared with trace levels (0.5–3 μg kg−1) in the South Island of New Zealand. Tetrodotoxin was detected in all the dissected organs but the siphons contained the highest concentrations of TTX at all sites analysed. A linear model of the depuration data identified a significant (p < 0.001) decline in total TTX concentrations in P. australis over the study period. The siphons maintained the highest amount of TTX across the entire depuration study. The digestive glands contained low concentrations at the start of the experiment, but this depurated rapidly and only traces remained after 21 days. These results provide evidence to suggest that P. australis does not produce TTX endogenously but obtains the neurotoxin from an exogenous source (e.g., diet) with the source more prevalent in warmer northern waters. The association of higher TTX concentrations in shellfish with warmer environments raises concerns that this toxin's distribution and abundance could become an increasing human health issue with global warming. Keywords: Biotoxin, Clam, Emerging threat, Geographic variability, Marine bivalves, Neurotoxinhttp://www.sciencedirect.com/science/article/pii/S2590171019300050 |
| spellingShingle | Laura Biessy Kirsty F. Smith D. Tim Harwood Michael J. Boundy Ian Hawes Susanna A. Wood Spatial variability and depuration of tetrodotoxin in the bivalve Paphies australis from New Zealand Toxicon: X |
| title | Spatial variability and depuration of tetrodotoxin in the bivalve Paphies australis from New Zealand |
| title_full | Spatial variability and depuration of tetrodotoxin in the bivalve Paphies australis from New Zealand |
| title_fullStr | Spatial variability and depuration of tetrodotoxin in the bivalve Paphies australis from New Zealand |
| title_full_unstemmed | Spatial variability and depuration of tetrodotoxin in the bivalve Paphies australis from New Zealand |
| title_short | Spatial variability and depuration of tetrodotoxin in the bivalve Paphies australis from New Zealand |
| title_sort | spatial variability and depuration of tetrodotoxin in the bivalve paphies australis from new zealand |
| url | http://www.sciencedirect.com/science/article/pii/S2590171019300050 |
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