The effects of delousing chemical, imidacloprid, on the copepod Acartia tonsa
The Norwegian aquaculture is critically important to the country’s industry and is the world largest exporter of Atlantic salmon (Salmo salar). However, the industry’s scale has led to an increase of louse pressure on both farmed and wild populations of salmonid species, with salmon louse (Lepeophth...
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The University of Bergen
2024
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ftunivbergen:oai:bora.uib.no:11250/3149473 2024-09-15T17:56:33+00:00 The effects of delousing chemical, imidacloprid, on the copepod Acartia tonsa Målen, Christoffer 2024-06-03T11:02:16Z application/pdf https://hdl.handle.net/11250/3149473 eng eng The University of Bergen KJEM399K 0 MAOM ORD 2024 VÅR https://hdl.handle.net/11250/3149473 Copyright the Author. All rights reserved Acartia tonsa EC LC Imidacloprid TKTD 752299 Master thesis 2024 ftunivbergen 2024-09-03T23:49:00Z The Norwegian aquaculture is critically important to the country’s industry and is the world largest exporter of Atlantic salmon (Salmo salar). However, the industry’s scale has led to an increase of louse pressure on both farmed and wild populations of salmonid species, with salmon louse (Lepeophtheirus salmonis) and Scottish louse (Caligus elongatus) having the greatest impact. Therefore, there are strict regulations in place to prevent louse infestations. To adhere to these regulations the industry uses chemotherapeutants and non-medical treatments. The chemotherapeutant imidacloprid was first approved for use in Norwegian aquaculture in 2021. Imidacloprid has a moiety resembling nicotine, which acts as a neurotoxin selectively targeting the insect’s central nervous system nicotinic acetylcholine receptors. Toxicity of imidacloprid has been extensively studied for insects and aquatic species, but little data for toxicity on marine species. In this study the acute toxicity of imidacloprid on the marine crustacean Acartia tonsa, using a 96-hours constant exposure and two pulse exposures, with a 24-hours and 72-hours intermediate non-exposure periods. Additionally, the stability of imidacloprid in saltwater solution was assessed during the 96-hours exposure. Raw data was further used to calculate LC and EC and make TKTD-RED-GUTS model. Experiments showed imidacloprid to be stable during the 96-hours and Acartia tonsa experiencing both immobilization and mortality in the 96-hours exposure, with EC10 = 0.06 mg/L, EC50 = 1.2 mg/L and EC90 = 25 mg/L after 24-hours and LC10 = 0.0021 mg/L, LC50 = 0.10 mg/L and LC90 = 4.3 mg/L after 96-hours. Both TKTD-RED-GUTS were poor fits compared with obtained mortality. The result obtained indicates Acartia tonsa would experience little effects based on treated release concentration, 0.30 µg/L, from the aquaculture. However, acute exposure from untreated treatment water, 20 mg/L, of imidacloprid could potentially have a significant impact on wild Acartia tonsa and potentially ... Master Thesis Atlantic salmon Salmo salar University of Bergen: Bergen Open Research Archive (BORA-UiB) |
institution |
Open Polar |
collection |
University of Bergen: Bergen Open Research Archive (BORA-UiB) |
op_collection_id |
ftunivbergen |
language |
English |
topic |
Acartia tonsa EC LC Imidacloprid TKTD 752299 |
spellingShingle |
Acartia tonsa EC LC Imidacloprid TKTD 752299 Målen, Christoffer The effects of delousing chemical, imidacloprid, on the copepod Acartia tonsa |
topic_facet |
Acartia tonsa EC LC Imidacloprid TKTD 752299 |
description |
The Norwegian aquaculture is critically important to the country’s industry and is the world largest exporter of Atlantic salmon (Salmo salar). However, the industry’s scale has led to an increase of louse pressure on both farmed and wild populations of salmonid species, with salmon louse (Lepeophtheirus salmonis) and Scottish louse (Caligus elongatus) having the greatest impact. Therefore, there are strict regulations in place to prevent louse infestations. To adhere to these regulations the industry uses chemotherapeutants and non-medical treatments. The chemotherapeutant imidacloprid was first approved for use in Norwegian aquaculture in 2021. Imidacloprid has a moiety resembling nicotine, which acts as a neurotoxin selectively targeting the insect’s central nervous system nicotinic acetylcholine receptors. Toxicity of imidacloprid has been extensively studied for insects and aquatic species, but little data for toxicity on marine species. In this study the acute toxicity of imidacloprid on the marine crustacean Acartia tonsa, using a 96-hours constant exposure and two pulse exposures, with a 24-hours and 72-hours intermediate non-exposure periods. Additionally, the stability of imidacloprid in saltwater solution was assessed during the 96-hours exposure. Raw data was further used to calculate LC and EC and make TKTD-RED-GUTS model. Experiments showed imidacloprid to be stable during the 96-hours and Acartia tonsa experiencing both immobilization and mortality in the 96-hours exposure, with EC10 = 0.06 mg/L, EC50 = 1.2 mg/L and EC90 = 25 mg/L after 24-hours and LC10 = 0.0021 mg/L, LC50 = 0.10 mg/L and LC90 = 4.3 mg/L after 96-hours. Both TKTD-RED-GUTS were poor fits compared with obtained mortality. The result obtained indicates Acartia tonsa would experience little effects based on treated release concentration, 0.30 µg/L, from the aquaculture. However, acute exposure from untreated treatment water, 20 mg/L, of imidacloprid could potentially have a significant impact on wild Acartia tonsa and potentially ... |
format |
Master Thesis |
author |
Målen, Christoffer |
author_facet |
Målen, Christoffer |
author_sort |
Målen, Christoffer |
title |
The effects of delousing chemical, imidacloprid, on the copepod Acartia tonsa |
title_short |
The effects of delousing chemical, imidacloprid, on the copepod Acartia tonsa |
title_full |
The effects of delousing chemical, imidacloprid, on the copepod Acartia tonsa |
title_fullStr |
The effects of delousing chemical, imidacloprid, on the copepod Acartia tonsa |
title_full_unstemmed |
The effects of delousing chemical, imidacloprid, on the copepod Acartia tonsa |
title_sort |
effects of delousing chemical, imidacloprid, on the copepod acartia tonsa |
publisher |
The University of Bergen |
publishDate |
2024 |
url |
https://hdl.handle.net/11250/3149473 |
genre |
Atlantic salmon Salmo salar |
genre_facet |
Atlantic salmon Salmo salar |
op_relation |
KJEM399K 0 MAOM ORD 2024 VÅR https://hdl.handle.net/11250/3149473 |
op_rights |
Copyright the Author. All rights reserved |
_version_ |
1810432751532244992 |