Adverse effects promoted by a commercial formulation of the insecticide Fipronil in liver biomarkers of sábalos (Prochilodus lineatus) juvenils

LOCH L; SANTILLAND DEIU A; ONDARZA P.M.; MIGLIORANZA K.S.B.; DE LA TORRE F.

Buenos Aires

Congreso; 11th Biennial Meeting Society of Environmental Toxicology and Chemistry Latinoamérica.; 2015

Society of Environmental Toxicology and Chemistry Latinoamérica.

Current Use Pesticides (CUPs) are emerging pollutants of special concern because their increasing input into the aquatic environments. Fipronil is a CUPs whose toxicity in insects is well documented, although limited knowledge concerning sublethal effects is available in other non-target organisms (eg, fishes). In this context, the biomarker responses promoted in juveniles of P. lineatus were evaluated after 48 h of exposure to a sublethal concentration of a commercial formulation of fipronil (Fp) dissolved in water (nominal value of 100 µg/L). The reversibility of these responses was also studied in exposed individuals after 15 days of permanence in tapwater under laboratory conditions (RFp). A Control series of unexposed individuals were simultaneously tested during exposure (Ctrl) and recovery (RCtrl) phases. Water samples were taken in order to measure levels of toxic. After the experimental period, fish were weighed, anesthetized and the liver were extracted. Condition factor (CF) and liver somatic index (LSI) were calculated, glutathione-S-transferase activity (GST) as well as the levels of lipid peroxidation by TBARS and antioxidant capacity against peroxyl (ACAP) were determined. CYP1A protein expression in liver was also estimated by means Western blotting. Differences between groups were analyzed using one way ANOVA and Tukey´s multiple comparisons. No significant differences among groups were detected in CF, LSI or GST. Fish exposure to Fp promoted an increase of 61% in TBARS levels but also in ACAP values (65%) showing a decrease in the antioxidant capacity respect to Ctrl group. Fipronil exposure also enhanced the response of CYP1A and reactive bands were observed in Fp group. Transference of exposed individuals to control media (RFp) promoted a non significant decrease in TBARS values respect RCtrl group, however ACAP values differentiated between these two groups. These results indicated that a short term exposure of formulated fipronil promoted in liver of this native species adverse effects showing that biotransformation processes were mediated by CYP1A and that oxidative damage was generated on lipids. Assayed recovery phase would also confirm the availability of reversing the adverse effects promoted by Fipronil.