Towards the standardization of Hydra vulgaris bioassay for toxicity assessments of liquid samples

The Hydra vulgaris bioassay is recognized as sensitive invertebrate test species for toxicity assessment of real-life environmental mixtures for enforcement and monitoring investigations. The purpose of this study was to characterize the intra-laboratory variability, study the influence of environme...

Full description

Saved in:
Bibliographic Details
Main Authors: G. Farley, P. Bouchard, C. Faille, S. Trottier, F. Gagné
Format: Article
Language:English
Published: Elsevier 2025-01-01
Series:Ecotoxicology and Environmental Safety
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S0147651324016361
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1823856882011340800
author G. Farley
P. Bouchard
C. Faille
S. Trottier
F. Gagné
author_facet G. Farley
P. Bouchard
C. Faille
S. Trottier
F. Gagné
author_sort G. Farley
collection DOAJ
description The Hydra vulgaris bioassay is recognized as sensitive invertebrate test species for toxicity assessment of real-life environmental mixtures for enforcement and monitoring investigations. The purpose of this study was to characterize the intra-laboratory variability, study the influence of environmental variables (temperature, luminosity, inter-individual and day of analysis) on ZnSO4 toxicity, a reference model toxicant for hydra. The sublethal (effect concentration for 50 % of hydra-EC50) and lethal (lethal concentration for 50 % of hydra-LC50) were determined based on characteristic morphological changes for this species. The influence of water hardness, ammonia and dissolved oxygen for over 50 real-life environmental liquid mixtures (effluents and leachates) were examined and compared with rainbow trout and Daphnia magna acute lethality tests. A control chart for Zn was developed from over 40 trials yielding an 96 h LC50 of 0.7 mg/L (0.66–0.77 95 % confidence interval-CI) and EC50 of 0.19 mg/L (0.17–0.21 95 % CI). The influence of 8 different analysts, the trial days and luminosity did not significantly influence the LC50 and EC50. Only higher temperature significantly decreased the toxicity of ZnSO4 within 15–30 °C range. The hydra bioassay was then practiced on more than 50 real-life effluents/leachates and compared with the 96 h rainbow trout and 48 h Daphnia magna survival tests. The data revealed that water hardness, dissolved oxygen and ammonia were not significantly correlated with either the LC50 or EC50 values. Moreover, the hydra LC50 data predictive (rank correlation of 0.6) the rainbow trout LC50 with the absence of false negatives. The hydra data were at least as if not more sensitive than the rainbow trout LC50 making it a relevant alternative method to reduce fish use for screening potentially toxic environmental mixtures.
format Article
id doaj-art-15b491468dda406d84e813da5ff669a2
institution Kabale University
issn 0147-6513
language English
publishDate 2025-01-01
publisher Elsevier
record_format Article
series Ecotoxicology and Environmental Safety
spelling doaj-art-15b491468dda406d84e813da5ff669a22025-02-12T05:29:46ZengElsevierEcotoxicology and Environmental Safety0147-65132025-01-01290117560Towards the standardization of Hydra vulgaris bioassay for toxicity assessments of liquid samplesG. Farley0P. Bouchard1C. Faille2S. Trottier3F. Gagné4Québec Laboratory for Environmental Evaluations, Environment and Climate Change Canada, Montréal, Québec, CanadaQuébec Laboratory for Environmental Evaluations, Environment and Climate Change Canada, Montréal, Québec, CanadaQuébec Laboratory for Environmental Evaluations, Environment and Climate Change Canada, Montréal, Québec, CanadaQuébec Laboratory for Environmental Evaluations, Environment and Climate Change Canada, Montréal, Québec, CanadaAquatic Contaminants Research Division, Environment and Climate Change Canada, Montréal, Québec, Canada; Corresponding author.The Hydra vulgaris bioassay is recognized as sensitive invertebrate test species for toxicity assessment of real-life environmental mixtures for enforcement and monitoring investigations. The purpose of this study was to characterize the intra-laboratory variability, study the influence of environmental variables (temperature, luminosity, inter-individual and day of analysis) on ZnSO4 toxicity, a reference model toxicant for hydra. The sublethal (effect concentration for 50 % of hydra-EC50) and lethal (lethal concentration for 50 % of hydra-LC50) were determined based on characteristic morphological changes for this species. The influence of water hardness, ammonia and dissolved oxygen for over 50 real-life environmental liquid mixtures (effluents and leachates) were examined and compared with rainbow trout and Daphnia magna acute lethality tests. A control chart for Zn was developed from over 40 trials yielding an 96 h LC50 of 0.7 mg/L (0.66–0.77 95 % confidence interval-CI) and EC50 of 0.19 mg/L (0.17–0.21 95 % CI). The influence of 8 different analysts, the trial days and luminosity did not significantly influence the LC50 and EC50. Only higher temperature significantly decreased the toxicity of ZnSO4 within 15–30 °C range. The hydra bioassay was then practiced on more than 50 real-life effluents/leachates and compared with the 96 h rainbow trout and 48 h Daphnia magna survival tests. The data revealed that water hardness, dissolved oxygen and ammonia were not significantly correlated with either the LC50 or EC50 values. Moreover, the hydra LC50 data predictive (rank correlation of 0.6) the rainbow trout LC50 with the absence of false negatives. The hydra data were at least as if not more sensitive than the rainbow trout LC50 making it a relevant alternative method to reduce fish use for screening potentially toxic environmental mixtures.http://www.sciencedirect.com/science/article/pii/S0147651324016361Hydra vulgarisReproducibilityEnvironmental variablesEffluentsLeachatesAlternative method
spellingShingle G. Farley
P. Bouchard
C. Faille
S. Trottier
F. Gagné
Towards the standardization of Hydra vulgaris bioassay for toxicity assessments of liquid samples
Ecotoxicology and Environmental Safety
Hydra vulgaris
Reproducibility
Environmental variables
Effluents
Leachates
Alternative method
title Towards the standardization of Hydra vulgaris bioassay for toxicity assessments of liquid samples
title_full Towards the standardization of Hydra vulgaris bioassay for toxicity assessments of liquid samples
title_fullStr Towards the standardization of Hydra vulgaris bioassay for toxicity assessments of liquid samples
title_full_unstemmed Towards the standardization of Hydra vulgaris bioassay for toxicity assessments of liquid samples
title_short Towards the standardization of Hydra vulgaris bioassay for toxicity assessments of liquid samples
title_sort towards the standardization of hydra vulgaris bioassay for toxicity assessments of liquid samples
topic Hydra vulgaris
Reproducibility
Environmental variables
Effluents
Leachates
Alternative method
url http://www.sciencedirect.com/science/article/pii/S0147651324016361
work_keys_str_mv AT gfarley towardsthestandardizationofhydravulgarisbioassayfortoxicityassessmentsofliquidsamples
AT pbouchard towardsthestandardizationofhydravulgarisbioassayfortoxicityassessmentsofliquidsamples
AT cfaille towardsthestandardizationofhydravulgarisbioassayfortoxicityassessmentsofliquidsamples
AT strottier towardsthestandardizationofhydravulgarisbioassayfortoxicityassessmentsofliquidsamples
AT fgagne towardsthestandardizationofhydravulgarisbioassayfortoxicityassessmentsofliquidsamples