Int. J. Dev. Biol. 56: 613 - 625 (2012)

https://doi.org/10.1387/ijdb.113469bq

Vol 56, Issue 6-7-8

Special Issue: The Hydra Model System

Hydra, a model system for environmental studies

Published: 5 June 2012

Brian Quinn*^1,2, François Gagné³, Christian Blaise³

¹Irish Centre for Environmental Toxicology, Galway-Mayo Institute of Technology, Galway, Ireland, ²Ryan Institute, National University of Ireland Galway, Galway, Ireland and ³Fluvial Ecosystem Research, Environment Canada, Montreal, Quebec, Canada

Abstract

Hydra have been extensively used for studying the teratogenic and toxic potential of numerous toxins throughout the years and are more recently growing in popularity to assess the impacts of environmental pollutants. Hydra are an appropriate bioindicator species for use in environmental assessment owing to their easily measurable physical (morphology), biochemical (xenobiotic biotransformation; oxidative stress), behavioural (feeding) and reproductive (sexual and asexual) endpoints. Hydra also possess an unparalleled ability to regenerate, allowing the assessment of teratogenic compounds and the impact of contaminants on stem cells. Importantly, Hydra are ubiquitous throughout freshwater environments and relatively easy to culture making them appropriate for use in small scale bioassay systems. Hydra have been used to assess the environmental impacts of numerous environmental pollutants including metals, organic toxicants (including pharmaceuticals and endocrine disrupting compounds), nanomaterials and industrial and municipal effluents. They have been found to be among the most sensitive animals tested for metals and certain effluents, comparing favourably with more standardised toxicity tests. Despite their lack of use in formalised monitoring programmes, Hydra have been extensively used and are regarded as a model organism in aquatic toxicology.

Keywords

Hydra, toxicity, bioassay, metal, regeneration