A Long-Term Time Series of <i>Dinophysis acuminata</i> Blooms and Associated Shellfish Toxin Contamination in Port Underwood, Marlborough Sounds, New Zealand
Blooms of the dinoflagellate <i>Dinophysis acuminata</i> occur every year in an important mussel cultivation area in Port Underwood, Marlborough Sounds, New Zealand. Annual maximum cell numbers range from 1500⁻75,000 cells L<sup>−1</sup> and over 25 years...
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| Format: | Article |
| Language: | English |
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MDPI AG
2019-02-01
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| Series: | Toxins |
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| Online Access: | https://www.mdpi.com/2072-6651/11/2/74 |
| _version_ | 1818039674336182272 |
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| author | Lincoln A. Mackenzie |
| author_facet | Lincoln A. Mackenzie |
| author_sort | Lincoln A. Mackenzie |
| collection | DOAJ |
| description | Blooms of the dinoflagellate <i>Dinophysis acuminata</i> occur every year in an important mussel cultivation area in Port Underwood, Marlborough Sounds, New Zealand. Annual maximum cell numbers range from 1500⁻75,000 cells L<sup>−1</sup> and over 25 years of weekly monitoring the <i>D. acuminata</i> bloom has never failed to exhibit peaks in abundance at some time between spring and autumn. During winter (June⁻August) the dinoflagellate is often undetectable, or at low levels (≤100 cells L<sup>−1</sup>), and the risk of diarrhetic shellfish poisoning (DSP)-toxin contamination over this period is negligible. Bloom occurrence may be coupled to the abundance of <i>D. acuminata</i> prey (<i>Mesodinium</i> sp.) but the mechanism by which it maintains its long-term residence in this hydrologically dynamic environment is unknown. The toxin profile of <i>D. acuminata</i> is dominated by pectenotoxin-2 (PTX-2) and dinophysistoxin-1 (DTX-1), but the cellular toxin content is low. It is rare that free DTX-1 is detected in mussels as this is invariably exclusively present as fatty acid-esters. In only five out of >2500 mussel samples over 16 years have the levels of total DTX-1 marginally exceeded the regulated level of 0.16 mg kg<sup>−1</sup>. It is also rare that free PTX-2 is detected in mussels, as it is generally only present in its hydrolysed non-toxic PTX-2 seco acid form. The <i>D. acuminata</i> alert level of 1000 cells L<sup>−1</sup> is often exceeded without DTX-1 residues increasing appreciably, and this level is considered too conservative. |
| first_indexed | 2024-12-10T08:02:23Z |
| format | Article |
| id | doaj.art-da10c8d744ce490cae6a1f016c2d97c8 |
| institution | Directory Open Access Journal |
| issn | 2072-6651 |
| language | English |
| last_indexed | 2024-12-10T08:02:23Z |
| publishDate | 2019-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Toxins |
| spelling | doaj.art-da10c8d744ce490cae6a1f016c2d97c82022-12-22T01:56:45ZengMDPI AGToxins2072-66512019-02-011127410.3390/toxins11020074toxins11020074A Long-Term Time Series of <i>Dinophysis acuminata</i> Blooms and Associated Shellfish Toxin Contamination in Port Underwood, Marlborough Sounds, New ZealandLincoln A. Mackenzie0Cawthron Institute, 98 Halifax Street, Nelson 7010, New ZealandBlooms of the dinoflagellate <i>Dinophysis acuminata</i> occur every year in an important mussel cultivation area in Port Underwood, Marlborough Sounds, New Zealand. Annual maximum cell numbers range from 1500⁻75,000 cells L<sup>−1</sup> and over 25 years of weekly monitoring the <i>D. acuminata</i> bloom has never failed to exhibit peaks in abundance at some time between spring and autumn. During winter (June⁻August) the dinoflagellate is often undetectable, or at low levels (≤100 cells L<sup>−1</sup>), and the risk of diarrhetic shellfish poisoning (DSP)-toxin contamination over this period is negligible. Bloom occurrence may be coupled to the abundance of <i>D. acuminata</i> prey (<i>Mesodinium</i> sp.) but the mechanism by which it maintains its long-term residence in this hydrologically dynamic environment is unknown. The toxin profile of <i>D. acuminata</i> is dominated by pectenotoxin-2 (PTX-2) and dinophysistoxin-1 (DTX-1), but the cellular toxin content is low. It is rare that free DTX-1 is detected in mussels as this is invariably exclusively present as fatty acid-esters. In only five out of >2500 mussel samples over 16 years have the levels of total DTX-1 marginally exceeded the regulated level of 0.16 mg kg<sup>−1</sup>. It is also rare that free PTX-2 is detected in mussels, as it is generally only present in its hydrolysed non-toxic PTX-2 seco acid form. The <i>D. acuminata</i> alert level of 1000 cells L<sup>−1</sup> is often exceeded without DTX-1 residues increasing appreciably, and this level is considered too conservative.https://www.mdpi.com/2072-6651/11/2/74<i>Dinophysis acuminata</i>dinophysistoxinspectenotoxinsPort UnderwoodNew Zealand |
| spellingShingle | Lincoln A. Mackenzie A Long-Term Time Series of <i>Dinophysis acuminata</i> Blooms and Associated Shellfish Toxin Contamination in Port Underwood, Marlborough Sounds, New Zealand Toxins <i>Dinophysis acuminata</i> dinophysistoxins pectenotoxins Port Underwood New Zealand |
| title | A Long-Term Time Series of <i>Dinophysis acuminata</i> Blooms and Associated Shellfish Toxin Contamination in Port Underwood, Marlborough Sounds, New Zealand |
| title_full | A Long-Term Time Series of <i>Dinophysis acuminata</i> Blooms and Associated Shellfish Toxin Contamination in Port Underwood, Marlborough Sounds, New Zealand |
| title_fullStr | A Long-Term Time Series of <i>Dinophysis acuminata</i> Blooms and Associated Shellfish Toxin Contamination in Port Underwood, Marlborough Sounds, New Zealand |
| title_full_unstemmed | A Long-Term Time Series of <i>Dinophysis acuminata</i> Blooms and Associated Shellfish Toxin Contamination in Port Underwood, Marlborough Sounds, New Zealand |
| title_short | A Long-Term Time Series of <i>Dinophysis acuminata</i> Blooms and Associated Shellfish Toxin Contamination in Port Underwood, Marlborough Sounds, New Zealand |
| title_sort | long term time series of i dinophysis acuminata i blooms and associated shellfish toxin contamination in port underwood marlborough sounds new zealand |
| topic | <i>Dinophysis acuminata</i> dinophysistoxins pectenotoxins Port Underwood New Zealand |
| url | https://www.mdpi.com/2072-6651/11/2/74 |
| work_keys_str_mv | AT lincolnamackenzie alongtermtimeseriesofidinophysisacuminataibloomsandassociatedshellfishtoxincontaminationinportunderwoodmarlboroughsoundsnewzealand AT lincolnamackenzie longtermtimeseriesofidinophysisacuminataibloomsandassociatedshellfishtoxincontaminationinportunderwoodmarlboroughsoundsnewzealand |