Toxicological hazard induced by sucralose to environmentally relevant concentrations in common carp (Cyprinus carpio).

Sucralose (SUC) is an artificial sweetener that is now widely used in North American and Europe; it has been detected in a wide variety of aquatic environments. It is considered safe for human consumption but its effects in the ecosystem have not yet been studied in depth, since limited ecotoxicological data are available in the peer-reviewed literature. This study aimed to evaluate potential SUC-induced toxicological hazard in the blood, brain, gill, liver and muscle of Cyprinus carpio using oxidative stress biomarkers. Carps were exposed to two different environmentally relevant concentrations (0.05 and 155µgL-1) for different exposure times (12, 24, 48, 72 and 96h). The following biomarkers were evaluated: lipid peroxidation (LPX), hydroperoxide content (HPC) and protein carbonyl content (PCC), as well as the activity of antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT). SUC was determined by high pressure liquid chromatography tandem mass spectrometry techniques (HPLC)-MS/MS. Results show a statically significant increase in LPX, HPC, PCC (P<0.05) especially in gill, brain and muscle, as well as significant changes in the activity of antioxidant enzymes in gill and muscle. Furthermore, the biomarkers employed in this study are useful in the assessment of the environmental impact of this agent on aquatic species.

Chronic exposure to pollutants in Madín Reservoir (Mexico) alters oxidative stress status and flesh quality in the common carp Cyprinus carpio.

Madín Reservoir (MR) is located on the Río Tlalnepantla in Mexico. Previous studies seeking to identify pollutants at this site evidence that MR water contains a considerable metal load as well as nonsteroidal anti-inflammatory drugs (NSAIDs) at concentrations above those determined suitable for aquatic life. This study aimed to evaluate whether chronic exposure to pollutants in MR alters oxidative stress status and flesh quality in muscle of the common carp Cyprinus carpio. The following biomarkers were evaluated in muscle of carp caught in the general area of discharge from the town of Viejo Madín: hydroperoxide content (HPC), lipid peroxidation (LPX), protein carbonyl content (PCC), and activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). Physicochemical and textural properties of muscle were also evaluated. Results show that the metals Al and Fe were accumulated in muscle of C. carpio at levels of 21.3 and 29.6 µg L(-1), respectively, and the NSAIDs diclofenac, ibuprofen, and naproxen at levels from 0.08 to 0.21 ng L(-1). Fish exposed to discharge from the town of Viejo Madín showed significant increases in HPC (9.77 %), LPX (69.33 %), and PCC (220 %) with respect to control specimens (p < 0.05). Similarly, enzyme activity increased significantly: SOD (80.82 %), CAT (98.03 %), and GPx (49.76 %). In muscle, physicochemical properties evidenced mainly significant reductions compared to control values while textural properties showed significant increases. Thus, water in this reservoir is contaminated with xenobiotics that alter some biological functions in C. carpio, a fish species consumed by the local human population.

Short and long-term exposure to diclofenac alter oxidative stress status in common carp Cyprinus carpio.

Diclofenac (DCF) has been detected in significant amounts in municipal treated wastewater effluent. Diverse studies report that trace concentrations of DCF may induce toxic effects on different aquatic organisms as well as developmental, reproductive and renal damage. This study aimed to determine whether short and long-term exposure to DCF alter the oxidative stress (OS) status in blood, muscle, gills, brain and liver of common carp Cyprinus carpio. The median lethal concentration of DCF at 96 h (96-h LC50) and subsequently the lowest observed adverse effect level were determined. Carp were exposed (short and long-term) to the latter value for different exposure times (4 and 24 days) and the following biomarkers were evaluated in gill, brain, liver and blood: hydroperoxides content (HPC), lipid peroxidation (LPX), protein carbonyl content (PCC) and the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Also, the DCF was determined by LC-MS/MS. Significant increases in HPC, LPX and PCC were observed respect to control (P < 0.05) particularly in blood, muscle, gill, brain and liver. SOD, CAT and GPx activity also increased in these organs, with respect to controls (P < 0.05). DCF concentrations decreased and increased in water system and carp, respectively. Cyprinus carpio exposed to DCF was affected in OS status during the initial days of the study (at 4 days), exhibiting an increased response at 24 days in blood and liver. In contrast, a decrease was observed in muscle, gills and brain at 24 days with respect to 4 days. In conclusion, DCF induces OS on blood, muscle, gills, brain and liver in the carp C. carpio in short and long-term exposure. The biomarkers employed in this study are useful in the assessment of the environmental impact of this agent on aquatic species.