Acute Toxicity of Anthracene In Adult Individuals of the Amphipod Hyalella curvispina

ESPERT NURIA; MORELL MALENA; VILLANOVA JORGELINA; MARDIROSIAN MARIANA; VEDELAGO SOFIA; LASCANO CECILIA; VENTURINO ANDRÉS

Congreso; SETAC Latín América 15th biennial meeting; 2023

One of the main economic activities of North Patagonia is oil and gas field exploitation. The region is alsocharacterized by large urban settlements, established along natural and artificial watercourses. Economicand anthropogenic activities generate pollutants that can reach aquatic resources, so their quality might beat risk. Anthracene is a polycyclic aromatic hydrocarbon (PAH) considered potentially harmful, whoseenvironmental analysis and monitoring is considered essential. In the last decades, there has been anincreasing concern about the presence of PAH in aquatic ecosystems due to their wide distribution andpotential adverse effects on living organisms, even at low concentrations. This study analyzed the acutetoxicity of anthracene in the native amphipod Hyalella curvispina, possible behavioral alterations, and thedynamics of anthracene in the exposure media. Individuals were collected from a reference site in MariMenuco Lake, Neuquén, Argentina. The amphipods were maintained and raised under laboratoryconditions. Groups of 10 adults were exposed to a range of anthracene concentrations in 250 ml of filteredand dechlorinated water, during 96 hours, at constant temperature of 23 ± 1°C and 16:8 h (L:D)photoperiod. Bioassays were carried out keeping equal proportions of adult male and female individuals perexperimental unit. The concentrations tested were 0.1, 0.5, 1, and 2 mg/l. Each concentration was tested bytriplicate and each exposure was repeated at least three times. Mortality and behavioral alterations wereemployed as endpoints to determine toxicological parameters. Anthracene concentrations throughout theassay were determined by direct fluorometry. No significant differences were observed between control andanthracene-exposed individuals with regards to mortality, so the LC50 could not be calculated. However,the observation of behavioral alterations allowed us to calculate a 24h-EC10 of 0.09 mg/l. Anthraceneconcentration decreased significantly in the presence of individuals, with a T1/2 of 36.5 hours. Surprisingly,our results suggest that the studied concentrations of anthracene are not lethal for the amphipod H.curvispina. Nevertheless, it generates behavioral alterations such as changes in reaction speed andstillness. This study is of great relevance because the progress made in the research of anthracene toxicityis scarce when compared to its ubiquitous presence in the environment.