Hydra vulgaris assay as environmental assessment tool for ecotoxicology in freshwaters: a review
A. Cera
A 1 , G. Cesarini A 1 , F. Spani A B and M. Scalici A
+ Author Affiliations
- Author Affiliations
A Department of Sciences, University of Rome ‘Roma Tre’, Viale Guglielmo Marconi 446, I-00146 Roma, Italy.
B Corresponding author. Present address: Departmental Faculty of Medicine and Surgery, Università Campus Bio-Medico di Roma, Unit of Diagnostic Imaging, Via Alvaro del Portillo 21, I-00128 Roma, Italy. Email: federica.spani@uniroma3.it
Marine and Freshwater Research 72(6) 745-753 https://doi.org/10.1071/MF20115
Submitted: 19 April 2020 Accepted: 17 September 2020 Published: 17 December 2020
Abstract
Freshwaters are vulnerable ecosystems owing to several anthropogenic impacts, including chemical pollution. Among existing model organisms, the cnidarian Hydra vulgaris is widely used for toxicological tests, with the aim of detecting either toxicity or teratogenicity of different dissolved chemicals. Given the widespread range of applications and developed assays, the aim of this review was to show and discuss the actual use of this model for ecotoxicological assessments in freshwaters as an ‘early warning system’. To achieve this goal, a thorough review was conducted by consulting several search engines for peer-reviewed international articles. Among all resulting articles from literature search, those focusing on H. vulgaris assay applied to environmental pollution were first selected (n = 19). Then, only articles that specifically tested freshwater samples collected directly in the field were considered (n = 4). The literature search highlighted that Hydra assays are suitable monitoring tools for freshwater ecotoxicity assessment. In addition, H. vulgaris allows testing diverse biomarkers (e.g. molecular, histological, morphological and behavioural) and exploring innovative research fields. So as to be able to assess the impact of emerging contaminants on both habitat and human health, the Hydra assays are demonstrating that they have an increasing potential that must be exploited.
Keywords: biological monitoring, early warning system, emergent contaminants, Hydra vulgaris, regeneration, teratogens.
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