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In the present study, in vitro cytotoxic and genotoxic effect of copper-zinc alloy nanoparticles (Cu-Zn ANPs) on human lung epithelial cells (BEAS-2B) were investigated. XTT test and clonogenic assay were used to determine cytotoxic effects. Cell death mode and intracellular reactive oxygen species formations were analyzed using M30, M65 and ROS Elisa assays. Genotoxic effects were evaluated using micronucleus, comet and γ-H2AX foci assays. Cu-Zn ANPs were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS) and zeta potential measurements. Characterization of Cu-Zn ANPs showed an average size of 200nm and zeta potential of -22mV. TEM analyses further revealed the intracellular localization of Cu-Zn ANPs in cytoplasm within 24h. Analysis of micronucleus, comet and γ-H2AX foci counts showed that exposure to Cu-Zn ANPs significantly induced chromosomal damage as well as single and double stranded DNA damage in BEAS-2B cells. Our results further indicated that exposure to Cu-Zn ANPs significantly induced intracellular ROS formation. Evaluation of M30:M65 ratios suggested that cell death was predominantly due to necrosis., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Domoic acid (DA) is a neurotoxic amino acid naturally produced in the marine environment by some diatom species belonging to the genus Pseudo-nitzschia. Although the neurotoxic properties of DA have been demonstrated, very little is known about in vivo genotoxicity of DA on aquatic organisms. In the present paper, an in vivo study on the genotoxic effects of domoic acid was carried out on a fish, Oreochromis niloticus, using the micronucleus test and the comet assay. The fish were exposed to three doses of domoic acid (1, 5 and 10 microg/g body weight) by intracoelomic injections. Ethyl methane sulphonate at a single dose of 5mg/l was used as positive control. Analysis of micronuclei, nuclear abnormalities and DNA damage were carried out on peripheral erythrocytes sampled 24, 48 and 72 h post-treatment. Our results revealed significant increases in the frequencies of micronuclei, nuclear abnormalities as well as DNA strand breaks and thus demonstrated the genotoxic potential of DA on fish.

The aim of the study was to evaluate the toxic and mutagenic effects of bottled purified and natural spring waters for drinking. The study presents the genotoxicologic results of drinking water samples packaged in polyethylene terephthalate (PET) bottles. Genotoxic agents have the potential to interact with DNA and may cause DNA damage. Endpoints analyzed included mitotic index (MI), replication index (RI), and sister chromatid exchange (SCE). An analysis of variance test (ANOVA) was performed to evaluate the results. A significant decrease in MI and RI was observed compared with negative control cultures, respectively, (p<0.05, p<0.01). It is found that SCE frequency increases compared with negative control. There is no significant difference between negative control and drinking water samples and among drinking water samples for sister chromatid exchange induction (p>0.05).

The genotoxic effects of mercury chloride and lead acetate were evaluated in vivo using the micronucleus (MN) assay on acridine-orange (AO) stained peripheral blood erythrocytes, gill and fin epithelial cells of Carassius auratus auratus. Fish were exposed to three different concentrations of mercury chloride (MC) (1 microg/, 5 microg/L and 10 microg/L) and lead acetate (LA) (10 microg/L, 50 microg/L and 100 microg/L) for 2, 4 and 6 days. A single dose of 5 mg/L cyclophosphamide was used as a positive control. In addition to micronuclei, nuclear buds (NBs) were assessed in the erythrocytes. The ratio of polychromatic and normochromatic erythrocytes (PCE/NCE) in peripheral blood was also evaluated to assess cytotoxicity. MN frequencies in all three tissues were elevated in fish exposed to both LA and MC. However, NBs showed different sensitivity to metal treatments. MN frequencies in both control and treated fish were highest in gill cells and generally lower in erythrocytes and fin cells. PCE/NCE rations decreased in relation to MC and LA treatments. The results of this study indicate that LA and MC have genotoxic and cytotoxic damage in fish and confirmed that AO staining is a suitable technique for in vivo MN test in fish.

Pesticides are widely used throughout the world in agriculture to protect crops and in public health to control diseases. Nevertheless, exposure to pesticides represents a potential risk to humans. This paper describes a study of possible genetic damage in the people living in regions contaminated with complex mixture of pesticides in Göksu Delta. In this study, used methods were chromosomal aberration (CA), sister chromatid exchange analysis (SCE) in the peripheral blood lymphocytes, and micronucleus (MN) assay in the buccal epithelial cells. In the present investigation, 32 affected subjects consist of 16 smoking and 16 non-smokings and an equal number of control subjects were assessed for genome damage. Micronucleus (MN), Broken egg (BE), Karyorrhexis (KR), Karyolysis (KL) and Binucleus (BN) frequencies were higher in affected subjects than in controls. Smoking had a statistically significant effect on the Micronucleus, Karyorrhexis and Binucleus frequencies for both the control and the exposed group. Also smoking and exposure affected the frequency of sister chromatid exchange and chromosomal aberrations compared with control groups.

Glyphosate is a widely used broad-spectrum weed control agent. In the present study, an in vivo study on the genotoxic effects of a technical herbicide (Roundup) containing isopropylamine salt of glyphosate was carried out on freshwater goldfish Carassius auratus. The fish were exposed to three doses of glyphosate formulation (5, 10 and 15 ppm). Cyclophosphamide at a single dose of 5 mg/l was used as positive control. Analysis of micronuclei, nuclear abnormalities and DNA damage were performed on peripheral erythrocytes sampled at intervals of 48, 96 and 144 h posttreatment. Our results revealed significant dose-dependent increases in the frequencies of micronuclei, nuclear abnormalities as well as DNA strand breaks. Our findings also confirmed that the alkaline comet assay and nuclear deformations in addition to micronucleus test on fish erythrocytes in vivo are useful tools in determining the potential genotoxicity of commercial herbicides.

The genotoxic effects of effluents from a petroleum refinery and a chromium processing plant were evaluated in Oreochromis niloticus (Pisces: Perciformes) using the micronucleus test. Fish were exposed to different concentrations (5, 10 and 20%, v/v) of the effluents for 3, 6 and 9 days. Micronucleus analyses were carried out on gill epithelial cells and peripheral blood erythrocytes. Nuclear abnormalities other than micronuclei, considered as genetic damage indicators, were also evaluated on erythrocytes. Cyclophosphamide at a single dose of 4 mg/L was used as a positive control. The results of this study showed that both effluents had genotoxic potential. On the other hand, the level of genetic damage induced by petroleum refinery effluent was considerably higher than that of chromium processing plant effluent. Our results further indicate that nuclear abnormalities other than micronuclei, such as blebbed and lobed nuclei, may also be used as indicators of genotoxic damage.

In this study, genotoxic potential of metronidazole, an antibiotic-antiparasitic agent widely used both clinical and veterinary areas, was evaluated using the piscine micronucleus test. Specimens of Oreochromis niloticus (Pisces: Cichlidae) were exposed to different concentrations (5, 10, 15mg/L) of metronidazole and 4mg/L cyclophosphamide (as positive control) for 24, 48 and 72h. A fluorescent staining technique with acridine orange (AO) was performed to improve the sensitivity of erythrocyte micronucleus assay with fish. AO selectively stains newly formed immature erythrocytes (PCEs) therefore allows to obtain more sensitive results by detection of the micronucleated PCEs differed than mature erythrocytes (NCEs) by their RNA-containing cytoplasm. The ratio of PCE/NCE in peripheral blood was also evaluated to assess cytotoxicity. As a result, it was observed that the frequencies of micronucleated PCEs increased both dose and time dependently while PCE/NCE ratios decreased. Our results revealed that metronidazole has cytotoxic and genotoxic effects on fish. The use of acridine orange staining technique also seems useful in assessment of short-term genotoxic effects of chemicals, when fish are used as experimental animal.

To study the effects of occupational exposure to petroleum derivates such as benzene, exfoliated buccal cells from 50 petrol station attendants and 50 age- and sex-matched control subjects were examined for micronucleus (MN) frequency. Frequencies of nuclear abnormalities (NA) other than micronuclei, such as binucleates, karyorrhexis and karyolysis, were also evaluated. Benzene exposure was ascertained by measuring urinary phenol levels. The mean urinary phenol level of station workers was found to be significantly higher than that of control subjects (P < 0.05). Analysis of buccal cells revealed that MN and NA frequencies in petrol station workers were significantly higher than in control subjects (P < 0.01) and also significantly related to smoking habit (P < 0.01). Our findings indicate that the petrol station workers are under risk of significant cytogenetic damage.