Mahmut Selvi

Sublethal cyfluthrin toxicity to carp (Cyprinus carpio L.) fingerlings: Biochemical, hematological, histopathological alterations

This study measures a whole series of biological endpoints, and histopathological and behavioral changes of carp (Cyprinus carpio L.) fingerlings in order to investigate the adverse effects of a sublethal concentration of 10 microg/L cyfluthrin for 48h and one week using the semi-static test system. The most significantly altered findings of this study was that total antioxidant status levels decreased in 48h, chloride levels decreased in one week, and sodium and phosphorous levels increased in the 48h-exposed group. Plasma cortisol increased in both the 48h-exposed and the one-week-exposed groups. The unique tissue was the brain that had an increased level of malondialdehyde after one week of exposure. Such biomarkers may be used in assessing adverse/toxic effects of pesticides as environmental stressors. Potential oxidative-stress-inducing effect of synthetic pyrethroid cyfluthrin, as lipid peroxidation, in addition to its sodium channel blocking, is reported for the first time as an additional mechanism of action.

Investigation of acute toxicity of permethrin on guppies Poecilia reticulata.

Permethrin, a synthetic pyrethroid pesticide and potential toxic pollutant contaminating aquatic ecosystems, was investigated in the present study for acute toxicity. Guppy fish (Poecilia reticulata) were selected for the bioassay experiments. The experiments were repeated 3 times and the 48-h LC(50) was determined for the guppies. The static test method of acute toxicity test was used. Water temperature was regulated at 20+/-1 degrees C. In addition, behavioral changes at each permethrin concentration were observed for the individual fish. Data obtained from the permethrin acute toxicity tests were evaluated using the probit analysis statistical method. The 48-h LC(50) value for guppy was estimated as 245.7 microg/l. Values in the range of 0.05-97.0 microg/l have been reported for various other fish species.

Evaluation of potential genotoxicity of five food dyes using the somatic mutation and recombination test.

In this study, different concentrations of five food dyes (amaranth, patent blue, carminic acid, indigotine and erythrosine) have been evaluated for genotoxicity in the Somatic Mutation and Recombination Test (SMART) of Drosophila melanogaster. Standard cross was used in the experiment. Larvae including two linked recessive wing hair mutations were chronically fed at different concentrations of the test compounds in standard Drosophila Instant Medium. Feeding ended with pupation of the surviving larvae. Wings of the emerging adult flies were scored for the presence of spots of mutant cells which can result from either somatic mutation or somatic recombination. For the evaluation of genotoxic effects, the frequencies of spots per wing in the treated series were compared to the control group, which was distilled water. The present study shows that carminic acid and indigotine demonstrated negative results while erythrosine demonstrated inconclusive results. In addition 25 mg mL(-1) concentration of patent blue and 12.5, 25 and 50 mg mL(-1) concentrations of amaranth demonstrated positive results in the SMART.

Investigation of acute toxicity of cadmium chloride (CdCl2 · H2O) metal salt and behavioral changes it causes on water frog (Rana ridibunda Pallas, 1771)

The 96-h LC(50) value of cadmium chloride (CdCl(2).H(2)O), a metal salt widely used in industry, was determined in the water frog (Rana ridibunda Pallas, 1771). The experiments were conducted in two series and a total of 140 frogs were used to determine acute toxicity. In addition, behavioral changes in the water frog were determined for each cadmium chloride concentration. Data obtained from the cadmium chloride investigation were evaluated by using the probit analysis statistical method and the 96 h LC(50) value for water frog was estimated to be 51.2 mg/l.

Sublethal toxicity of esbiothrin relationship with total antioxidant status and in vivo genotoxicity assessment in fish (Cyprinus carpio L., 1758) using the micronucleus test and comet assay

Esbiothrin, synthetic pyrethroid with quick activity against insects, is widely used against household pests and in public health. Despite widespread use, data on ecotoxicity and genotoxic effects are extremely scarce. The aim of the present study is to evaluate the genotoxic potential of esbiothrin on a model fish species Cyprinus carpio L., 1758 (Pisces: Cyprinidae, koi) using the micronucleus test and comet assay in peripheral blood erythrocytes. Effects of two sublethal exposure concentrations on plasma total antioxidant status (TAS mmol/L), and Hct values were examined. On the basis of the 96 h LC50 data from U.S. EPA ecotox database (32 μg/L) two sublethal exposure concentrations (5 and 10 μg/L) were used together with ethyl methanesulfonate (EMS) (5 mg/L) as positive control. Five fish were used for each dose/duration group (24, 48, and 72 h) under controlled laboratory conditions. The fish showed behavioral changes at the higher dose. Plasma TAS (mmol/L) levels decreased in 24 h; an increase was observed slightly for 48 and obviously for 72 h in both exposure doses. Similarly, hematocrit (Hct) values differed between exposure duration but no significant differences in mean values were found between groups of the same exposure time. The general trend was a rise after 48 h, which decreased afterwards. Our results revealed significant increases in the frequencies of micronuclei and levels of DNA strand breaks and thus demonstrated the genotoxic potential of this pesticide on fish, a nontarget organism of the aquatic ecosystem. To our knowledge this is the first study to report observable genotoxic effects of esbiothrin on fish.

Investigation of acute toxicity of (2,4-dichlorophenoxy)acetic acid (2,4-D) herbicide on larvae and adult Nile tilapia (Oreochromis niloticus L.)

A 48h LC(50) values of (2,4-dichlorophenoxy)acetic acid (2,4-D), a widely used agricultural herbicide, were determined on the larvae and adult Nile tilapia (Oreochromis niloticus L.). Each test was repeated three times. The data obtained were statistically evaluated by the use of the E.P.A computer program based on Finneys probit analysis method and a 48h LC(50) value for Nile tilapia (O. niloticus L.) larvae and adults were found to be 28.23mg/L and 86.90mg/L, respectively in a static bioassay test system. 95% lower and upper confidence limits for the LC(50) were 22.55-32.98 and 80.67-92.80mg/L, respectively. Water temperature was 24±1°C. Behavioral changes of both tilapia life forms were examined for various herbicide concentrations.

Sublethal propoxur toxicity to juvenile common carp (Cyprinus carpio L., 1758): biochemical, hematological, histopathological, and genotoxicity effects.

The sublethal toxicological and genotoxic potential of propoxur, a widely used carbamate insecticide against household pests, in veterinary medicine, and in public health, was evaluated on carp as a model species (Cyprinus carpio L., 1758) using the erythrocyte micronucleus test. Based on the 96-h lethal concentration, 50% (LC50) data from the U.S. Environmental Protection Agency ECOTOX Database (10 mg/L), a sublethal exposure concentration of 5 mg/L was used under static bioassay laboratory conditions. Histopathological evaluation showed no significant changes in spleen, intestine, muscle, or skin tissues. However, the following conditions were recorded: hyperemia, branchitis in primary lamella, and telangiectasis, hyperplasia, fusion, epithelial lifting, and epithelial desquamation in secondary lamella of gill tissues; hemorrhage, destruction, prenephritis, and inflammation and desquamation in the tubules; edema in the kidney; passive hyperemia, albumin, and hydropic degeneration in the liver; and hyperemia, chromatolysis, and glial proliferation in brain tissues. No statistically significant increases in micronuclei frequencies were found. Hematological parameters showed decreased hematocrit values and mean corpuscular volume values, as well as increased erythrocyte and leukocyte counts compared with the control group (p < 0.01). Plasma glucose, cholesterol, triglycerides, phosphorus, sodium, total plasma protein, chloride, and aspartate aminotransferase levels were increased (p < 0.01). Only plasma calcium and potassium levels decreased in the experimental group. Propoxur has an ecotoxicological potential on fish, a nontarget organism.

The effect of L-NAME administrations after oral mucosal incision on wound NO level in rabbit

The aim of the current study was to comparatively investigate the effect of inhibition of nitric oxide (NO) production by N-nitro-L-arginine methyl ester (L-NAME), an isoform non-specific inhibitor of nitric oxide synthase (NOS), after oral mucosal incision on wound tissue NO levels. A standard incision was applied to the oral mucosa of rabbits. After oral mucosal incision, rabbits were divided into five groups as follows: (1) Untreated incisional group (control); (2) Titanium (Ti) implanted group; (3) Ti + Polyethylene glycol (PEG) 4000 implanted group; (4) Ti + PEG 4000 + L-NAME (2 × 10−4 M) implanted group and (5) i.p. L-NAME administrated group (10 mg/kg). At 5 days after oral incision operations, wound tissue strips and plasma were obtained from rabbits. Oral wound tissue and plasma nitric oxide, plasma thiobarbituric acid reactive substances (TBARS) and total sulfhydryl group (RSH) levels were investigated. Plasma TBARS and NOx levels decreased after i.p. L-NAME administration. Total RSH group levels were not changed in all groups (p>0.05). This means that L-NAME inhibits the deteriorating effects of free radicals without affecting healing. L-NAME in PEG and titanium also has no effect on tissue and plasma NOx levels. These findings indicate that NO generation will not be affected both Ti and local nitric oxide synthase (NOS) inhibitor. (Mol Cell Biochem 278: 65–69, 2005)

How Sublethal Fenitrothion is Toxic in Carp (Cyprinus carpio L.) Fingerlings.

ABSTRACT The purpose of this study was to evaluate the effects of fenitrothion, an organophosphothionate insecticide, on selected serum hematological and biochemical parameters of carp (Cyprinus carpio L.) fingerlings and investigate histopathological changes after acute dose of exposure. Among those, cortisol and glucose are evaluated as responses of early life stages of carp to acute stress and hematological blood parameters are evaluated to investigate the mechanism of toxicity via histopathological changes to the standard test organism. No significant histological findings were observed in carp tissues (gills, liver, kidneys, spleen, gonads, brain, muscle, and skin) exposed to a sublethal concentration of 10 mg/L fenitrothion and controls. Hematocrit and erythrocyte counts were decreased significantly by exposure to fenitrothion when compared to the control group (25.26% ± 0.82%, 1455 ± 90.3 [103/μL] vs. 28.83% ± 1.60%, 1865 ± 74.5 [103/μL], P < 0.05), respectively. Leucocyte and thrombocyte counts did not change. Increases in plasma cortisol levels were found in the experimental group compared to controls (34.2 ± 1.9 vs. 18.0 ± 2.2, P < 0.05) respectively, while glucose, chloride, sodium, potassium, phosphorous, and brain MDA and FOX levels did not show significant differences from those of control (P > 0.05). As a result, we can conclude that early life stages of fish are very susceptible to the adverse effects of toxicants.

Genotoxicity assessment of carp (Cyprinus carpio L.) fingerlings by tissue DNA damage and micronucleus test, after environmental exposure to fenitrothion

The purpose of this study was to evaluate the adverse effects of sublethal doses of fenitrothion, an organophosphothionate insecticide on brain, gill, liver, and muscle tissues as a ratio of 8-OHdG to dG to indicate the DNA damage and erythrocyte micronucleus frequency for genotoxicity of carp (Cyprinus carpio L.) fingerlings. In our study, the mean weights and lengths of the fish (n = 4–12) were 31.13 ± 14.24 g and 12.53 ± 1.41, respectively. Before the experiment, fish were maintained in aerated dechlorinated tap water at 21.8 ± 1°C and fed daily with commercial feed at a rate of 2% of their body weights. Experiments were conducted under static conditions in the aquaria. Technical grade (95%) fenitrothion was diluted in acetone to give a dosing solution of 10 mg/L. The increased lesions/106 DNA bases (p < 0.05) of liver tissue of exposure group (0.49 ± 0.18) was observed when compared to control group (0.28 ± 0.30). There was not any significant differences between brain tissues, no damage were detectable in gill and muscle tissues of control groups, and in exposure groups altered levels of damage were detected for gill (0.06 ± 0.05) and muscle (0.16 ± 0.21) tissues. The increased micronucleus frequencies (%) in erythrocytes of carp following the exposure to 48 h fenitrothion (6.43 ± 3.89; p<0.05) was observed when compared to control group (1.29 ± 1.03). The available data indicate that there is still lack of well-established dose–response relationships between occupational or environmental exposures and the induction of 8-OHdG. Such biomarkers may be used in assessing adverse/toxic effects of pesticides as environmental stressors.