The amphipod Parhyale hawaiensis as a promising model in ecotoxicology

Near-shore marine/estuarine environments play an important role in the functioning of the marine ecosystem and are extremely vulnerable to the presence of chemical pollution. The ability to investigate the effects of pollution is limited by a lack of model organisms for which sufficient ecotoxicological information is available, and this is particularly true for tropical regions. The circumtropical marine amphipod Parhyale hawaiensis has become an important model organism in various disciplines, and here we summarize the scientific literature regarding the emergence of this model within ecotoxicology. P. hawaiensis is easily cultured in the laboratory and standardized ecotoxicity protocols have been developed and refined (e.g., miniaturized), and effects of toxicants on acute toxicity (Cd, Cu, Zn, Ag, ammonia, dyes, pesticides, environmental samples), genotoxicity as comet assay/micronuclei, and gene expression (Ag ion and Ag nanoparticles) and regeneration (pesticides) have been published. Methods for determination of internal concentrations of metals (Cu and Ag) and organic substances (synthetic dye) in hemolymph were successfully developed providing sources for the establishment of toxicokinetics models in aquatic amphipods. Protocols to evaluate reproduction and growth, for testing immune responses and DNA damage in germ cells are under way. The sensitivity of P. hawaiensis, measured as 50% lethal concentration (LC50), is in the same range as other amphipods. The combination of feasibility to culture P. hawaiensis in laboratory, the recent protocols for ecotoxicity evaluation and the rapidly expanding knowledge on its biology make it especially attractive as a model organism and promising tool for risk assessment evaluations in tropical environments.

Automated summary

Near-shore marine/estuarine environments are important in the marine ecosystem, but are vulnerable to chemical pollution. The lack of model organisms with sufficient ecotoxicological information limits the ability to investigate pollution effects, especially in tropical regions. However, the circumtropical marine amphipod Parhyale hawaiensis has emerged as an important model organism in ecotoxicology. It can be easily cultured in the laboratory, and standardized ecotoxicity protocols have been developed. Studies have been conducted on the effects of various toxicants, genotoxicity, gene expression, and regeneration. Methods for determining internal concentrations of metals and organic substances have been successfully developed. Research on reproduction, growth, immune responses, and DNA damage is ongoing. P. hawaiensis has a similar sensitivity to other amphipods, and its feasibility for laboratory culture, recent ecotoxicity evaluation protocols, and expanding knowledge on its biology make it an attractive model organism and tool for risk assessment in tropical environments.