Effects of the exposure of fish to triazine herbicides.

Triazines are an important group of herbicides, which have been used extensively or selectively both in agricultural and non-agricultural areas worldwide for more than fifty years to control broadleaf and some grassy weeds. As a consequence of their massive application, they have become and remain significant environmental pollutants, especially in aquatic ecosystems. Fish are an integral part of the aquatic environment and are, therefore, suitable models for the study of the behavioral, biological, and biochemical effects of triazine exposure. We have summarized and evaluated the effects of triazine herbicides on fish in order to provide an overview of current information on triazines. The overall effects of triazine herbicide exposure on the physiology of fish were evaluated by considering a variety of parameters in a number of reports. Haematological and biochemical profiles of blood provide important information about the internal environment of the organism and the general physiology and health status of triazine exposed fish. According to studies using biotransformation and bioaccumulation indices to estimate the effects of triazines on fish, changes in fish metabolism reflect the pollution of the environment by these herbicides. The responses of antioxidant defence systems in fish to triazine exposure could be an adaptive mechanism to protect the fish from triazine-induced oxidative stress. Acute exposure to triazines affects reproduction or reproductive development in fish; however, some triazines did not affect fish behavior during long-term exposure to low concentrations. Nevertheless, an impact on the overall behavioral response of fish cannot be excluded.

Decrease in the antioxidant capacity in beverages containing tea extracts during storage.

The aim of this work was to determine antioxidant capacity of beverages containing black, white, and green tea extracts using the photochemiluminescence method, and to monitor its changes based on the storage temperature and time. Samples were stored at two different temperatures (refrigerated at 4°C and laboratory temperature 22°C), analyzed after opening of the original package, and consequently after 4 and 7 days. Results of the antioxidant capacity are expressed as the standard equivalents, that is, ascorbic acid in mmol/L. The highest mean value of the antioxidant capacity was found after opening of the original package in fruit-juice-enriched samples and totaled 9.793 mmol/L. This group revealed significant dependence (P < 0.05) not only on the storage time, but also temperature. In samples without added fruit juices containing preservatives the value was 0.428 mmol/L. This group showed significant dependence (P < 0.05) on the decrease of antioxidant capacity only when based on the storage time. Samples without fruit juices or preservatives showed significant decrease in the antioxidant capacity (P < 0.05) after 4 days of storage based on the storage time. The dependence on temperature was revealed only after 7 days of storage.

Possibilities of enhancing the colour of egg yolk.

BACKGROUND: This study attempts to compare two possibilities of enhancing the colour of egg yolk. One of them is based on the ecological rearing of laying hens on natural green grass whereas the other uses a feeding dose supplemented with natural pigments in laying hens reared in individual cages. Is it possible to distinguish these two technologies using yolk colour determination in the CIELAB system? RESULTS: Yolk colour parameters such as L*, a*, and b* in the group of grazed hens are significantly different (α = 0.001) from those observed in hens reared in cages. The yolk colour shows a darker, redder and more yellow colour. The greatest difference was seen in the red colour parameter, a*, that increased more than twice. Visually, this means a shift towards a more orange colour. Compared to grazing in the meadow (ΔE* = 13.257), the addition of artificial pigments in the feed resulted in a more significant increase in the parameter ΔE* (CIE total colour difference), with the greatest value of ΔE* being observed with the use of both pigments (ΔE* = 24.265). CONCLUSION: Grazing increases the parameter a* whereas the values of the parameter C*(ab) remain relatively low. The parameter ΔE* is significantly lower in the case of grazing as compared to the supplementation of the feed with pigments. However, colourity parameters cannot be used as a specific standard to identify a particular grazing technology as their values vary during the laying period.

Fish oil and cod liver as safe and healthy food supplements.

OBJECTIVES: The aim of this study is to determine the content of mercury, methylmercury and persistent organic pollutants in the capsules filled with fish oil from marine fish and in the canned cod liver and find out, whether analyse products are safe and suitable for human consumption. METHODS: Total mercury was determined by cold vapour atomic absorption spectroscopy on an AMA-254 (Altec Ltd., Czech Republic) single-purpose mercury analyzer. Methylmercury in the cod liver in the form of chlorid methylmercury was determined by gas chromatography. Seven indicator congeners of PCB (PCB 28, 52, 101, 118, 138, 153, 180), HCH, HCB, DDT and its degradation products DDE and DDD, were determined by gas chromatography-mass spectrometry. RESULTS: In capsules filled with fish oil (n=19) total Hg levels were in the range of 0.013 to 2.03 ng/g. All the capsule oil samples analyzed for MeHg were below the detection limit. The highest concentration of total Hg was found in cod liver - can A (0.223 ng/g). The maximum percentage of MeHg in total Hg concentration was found in a liver sample - can B. The values of alpha-, beta-, gamma-, delta- HCH and of HCB were found below the detection limits in all the capsule samples analyzed. In eight capsules, the presence of highly lipophilic PCB congeners was demonstrated. DDT and its important DDE metabolite were found in ten samples. In canned cod liver the highest concentration of all PCB congeners was demonstrated in can D. The lowest congener concentrations, however, were found in smoked cod liver - can C. DDT with its main metabolite DDE was detected in can C. No additional DDT and DDD persistent pollutants were detected. CONCLUSIONS: The consumption of fish oil in capsules, and canned cod liver is safe and healthy and should be encouraged.

Protein carbonyls and traditional biomarkers in pigs exposed to low-dose γ-radiation.

Response of pigs to irradiation manifested by production of protein carbonyls and adaptable enzymes was studied in two experiments. In one experiment, 10 mixed-sex pigs were exposed to 0.5 Gy whole body (60)Co irradiation. In the other experiment, another batch of 10 pigs was exposed to 1.0 Gy half-body irradiation. Unlike those exposed to half-body irradiation, the pigs exposed to whole-body irradiation showed significant increase in protein carbonyls by 73%, and a decrease in cholesterol by 25.7%, compared to the control group. In both cases of dose-dependent irradiation exposure, pigs showed a decrease in alanine aminotransferase activity compared with the control group. At the dose of 1 Gy, ALT activity decreased significantly by 27.7%. Aspartate aminotransferase activity in pigs after half-body irradiation decreased significantly by 65.5%. Although low doses of ionizing radiation were applied, monitoring of the above biochemical parameters helped define the pigs' biological response.