Effect of neurotoxic compounds on ephyrae of Aurelia aurita jellyfish

Abstract

The aim of this study was to analyze the toxicity of two neurotoxic compounds on the ephyra stage of the Scyphozoan jellyfish Aurelia aurita, an innovative and sensitive model organism recently proposed in ecotoxicological bioassays. Indeed, jellyfish play an important role in the marine ecosystem, being a key component of the gelatinous zooplankton and of the marine food web, but are not represented in routine ecotoxicology. In this study, ephyrae were exposed to several concentrations (0, 0.1, 0.5, 1, 5, 10, 50 mg l -1 ) of eserine (ES) and chlorpyrifos (CPF), a carbamate and an organophosphorous compound, respectively, in order to analyze their toxic effect on this model organism. Acute (% of immobility) and behavioral (% alteration of frequency of pulsations) end-points were investigated after 24 and 48 h of exposure. Exposure to both compounds caused a dosedependent effect, and for each end-point, it was possible to quantify these effects by means of EC 50 . Results highlighted how these compounds reported a high toxicity for marine organisms and exerted their toxic effect on this innovative biological model (in particular, CPF resulted to be more toxic than ES), which proved to be more sensitive than other marine invertebrates commonly used for ecotoxicological bioassays.

Chlorpyrifos: pollution and remediation

“…Acute and chronic effects of chlorpyrifos on various amphibians as well as aquatic vertebrates and invertebrates have been well reviewed by Corbin et al (2009). Ephyra stage of the Scyphozoan jellyfish Aurelia aurita was recently reported susceptible to dose dependent effect of chlorpyrifos (Costa et al 2015). All these together indicate apprehension about the potential hazards of chlorpyrifos to aquatic life.…”

Life history traits and previous exposure predict resistance to UV irradiation in the freshwater cnidarian Hydra oligactis

“…Such an effect, in which sublethal exposures to stress cause an improved capacity to withstand higher doses or result in higher growth or reproduction at subsequent time intervals (a phenomenon known as hormesis; Forbes ; Gems & Partridge ), is known to occur in cnidarians (Stebbing ; Lucas & Horton ; Costa et al. ) and in hydra in particular (Stebbing & Pomroy ; Schaible et al. ; de Jong et al.…”

“…(4) Does a previous exposure to low-level UV radiation influence subsequent responses? Such an effect, in which sublethal exposures to stress cause an improved capacity to withstand higher doses or result in higher growth or reproduction at subsequent time intervals (a phenomenon known as hormesis ;Forbes 2000;Gems & Partridge 2008), is known to occur in cnidarians (Stebbing 1981;Lucas & Horton 2014;Costa et al 2015) and in hydra in particular (Stebbing & Pomroy 1978;Schaible et al 2011;de Jong et al 2016; but see T€ ok€ olyi et al 2014). (5) Is there variation between individuals in hormetic response, and does it depend on age, size, or reproductive investment (budding rate) of polyps?…”

Effects of the harmful dinoflagellate Ostreopsis cf. ovata on different life cycle stages of the common moon jellyfish Aurelia sp.

“…For example, Faimali et al (2014) investigated the influence of different culturing and methodological parameters (temperature, photoperiod, ephyrae density and age) on considered end-points and standardized a protocol for organisms' maintenance and testing; then, ephyrae were exposed to two well-known reference toxic compounds (Cadmium Nitrate and Sodium Dodecyl Sulphate). Successively, Costa et al (2015) described another toxicity bioassay where Aurelia aurita ephyrae were used as model organism to test noxious effects of tow neurotoxic compounds, namely eserine (ES) and chlorpyrifos (CPF). In the case of toxicology bioassay on polyps, even less data are reported in literature, mostly addressing accumulation of contaminants, such as heavy metals (e.g.…”