River sediments may contain a huge variety of environmental contaminants and play a key role in the ecological status of aquatic ecosystems. Contaminants adsorbed to sediments and suspended solids may contribute directly or after remobilization to an adverse ecological and chemical status of surface water. In this subproject of the joint research project DanTox, acetonic Soxhlet extracts from three German river sediments from the River Rhine (Altrip and Ehrenbreitstein with moderate contamination) and River Elbe (Veringkanal Hamburg heavily contaminated) were prepared and redissolved in dimethyl sulfoxide (DMSO). These extracts were analyzed with a standard bioassay battery with organisms from different trophic levels (bacteria, algae, Daphnia, fish) as well as in the Ames test and the umuC test for bacterial mutagenicity and genotoxicity according to the respective OECD and ISO guidelines. In total, 0.01 % (standard) up to 0.25 % (only fish embryo test) of the DMSO sediment extract was dosed to the test systems resulting in maximum sediment equivalent concentrations (SEQ) of 2 up to 50 g l⁻¹. The sediment of Veringkanal near Hamburg harbor was significantly more toxic in most tests compared to the sediment extracts from Altrip and Ehrenbreitstein from the River Rhine. The most toxic effect found for Veringkanal was in the algae test with an EᵣC₅₀ (72 h) of 0.00226 g l⁻¹ SEQ. Ehrenbreitstein and Altrip samples were about factor 1,000 less toxic. In the Daphnia, Lemna, and acute fish toxicity tests, no toxicity at all was found at 2 g l⁻¹ SEQ. corresponding to 0.01 % DMSO. Only when increasing the DMSO concentration the fish embryo test showed a 22-fold higher toxicity for Veringkanal than for Ehrenbreitstein and Altrip samples, while the toxicity difference was less evident for the Daphnia test due to the overlaying solvent toxicity above 0.05 % dimethyl sulfoxide (DMSO). The higher toxicities observed with the Veringkanal sample are supported by the PAH and PCB concentrations analyzed in the sediments. The sediment extracts of Altrip and Veringkanal were mutagenic in the Ames tester strain TA98 with metabolic activation (S9-mix). The findings allow a better ecotoxicological characterization of the sediments extensively analyzed in all subprojects of the DanTox project (e.g., Garcia-Kaeufer et al. Environ Sci Pollut Res. doi: 10.1007/s11356-014-3894-4 , 2014; Schiwy et al. Environ Sci Pollut Res. doi: 10.1007/s11356-014-3185-0 , 2014; Hollert and Keiter 2015). In the absence of agreed limit values for sediment extracts in standard tests, further data with unpolluted reference sediments are required for a quantitative risk assessment of the investigated polluted sediments.

In the present study, the coupling of adsorption capacity and photocatalytic efficiency of two different industrially produced titania catalysts was investigated and compared. The azo dye Reactive Red 195 was selected as a model compound. The tested catalysts, PK-10 and PK-180, exhibited different adsorption capacities due to their significant difference in their specific surface, but both have proven to be effective photocatalysts for photodegradation of the studied dye. PK-10 exhibited strong adsorption of the studied dye due to its high specific surface area, while the second studied catalyst, PK-180, demonstrated negligible adsorption of Reactive Red 195. The effect of the pH, the concentration of the catalyst and the initial concentration of the dye appear to affect the photocatalytic rate. The effect of the presence of humic acids and inorganic ions was also examined, while the contribution of various reactive species was indirectly evaluated through the addition of various scavengers. To evaluate the extent of mineralisation of the studied dye, total organic carbon (TOC) measurements during the experiment were also conducted. Besides total colour removal, evident reduction of TOC was also achieved using both catalysts.

The objective of this study is to investigate the hepatotoxicity and nephrotoxicity of organic contaminants in wastewater-irrigated soil using in vivo and in vitro experiments on mice and rat. Soil samples were collected from a wastewater-irrigated area and groundwater-irrigated area, i.e. clean water-irrigated area as control group. The organic contaminants were extracted using an ultrasonic oscillator. In vivo experiment was performed by contamination of hepatocytes of rat using the organic extract, and comet assay was used to analyse the DNA damage of hepatocytes. For in vitro experiment, mice were first gavaged with extracts, and then the indicators for kidney functions, liver functions and oxidative damage of tissues were investigated. The result shows, for in vitro experiments, compared with clean water-irrigated area groups, the average DNA tailing length for the wastewater-irrigated area group is larger, and for the wastewater-irrigated area groups with extract concentration 0.6 g/ml and 0.9 g/ml, the tailing rate increases significantly (P < 0.05). For in vivo experiments, the change of weight across each group shows no significant difference (P < 0.05). Compared with clean water-irrigated groups, the liver indices have decreased for all groups of the wastewater-irrigated area, while both kidney and liver indices decreased for wastewater-irrigated area high-dose group (P < 0.05 or P < 0.01). The total proteins for wastewater-irrigated low-dose group and Gamma-glutamyl transpeptidase, creatinine for high-dose group all increased (P < 0.01). Compared with the reagent control group, total superoxide dismutase activity of liver for wastewater-irrigated groups and glutathione peroxidase activity for high-dose group, malondialdehyde content all decreased (P < 0.05 or P < 0.01); glutathione peroxidase activity of kidney tissue for wastewater-irrigated high-dose group decreased (P < 0.01). The result shows that the joint toxicity in extracts of wastewater-irrigated soil is able to cause DNA damage of hepatocytes in rats, changes of liver functions in mice and lead to oxidative damage of liver and kidney.

Cloud samples were collected during the summer of 2011 and the spring of 2012 at a high-elevation site in southern China in an effort to examine the chemical characteristics of acid clouds. In total, 141 cloud samples were collected during 44 cloud events over the observation period. The dominant ionic species were SO₄ ²⁻, NH₄ ⁺, and NO₃ ⁻, contributing approximately 75 % of the total inorganic ion concentration. The primary acidifying factors were sulfate and nitrate, and the primary neutralizing factors were ammonium and calcium. The volume-weighted mean (VWM) pH of the cloud water was 3.79, indicating an acidic nature. In these cloud samples, Zn and Al exhibited the highest trace metal concentrations, contributing approximately 60 % of the total trace element concentration. Toxic metals, such as Pb, Ba, As, and Cr, were detected at high concentrations, indicating potential hazards for human health, vegetation, and waters in this region. Visual MINTEQ 3.0 results revealed that the majority of Zn(II) and Pb(II) existed in the form of free ions. The behavior of Al, however, differed from the behaviors of zinc and lead. The temporal variation in cloud chemistry indicated that temperature, sandstorms, and long-range transport could affect the concentrations of species. During the lifetime of a cloud event, the concentrations of the chemical species were controlled by the transfer of gases or particles to liquid droplets.

Significant losses in harvested melon can be directly attributable to decay fungi. In the present study, the use of UV-C treatment combined with biocontrol yeast, Pichia cecembensis, was evaluated for their ability to control postharvest decay of melon fruits after they were artificially inoculated with Fusarium oxysporum and Alternaria alternata. Natural infection of fruit was also assessed. As a stand-alone treatment, UV-C or P. cecembensis significantly reduced Fusarium rot and Alternaria rot, and also the level of natural infection on melon fruit, relative to the untreated control. The combination of UV-C or P. cecembensis, however, provided a superior level of decay control on artificially inoculated and naturally infected fruit, compared to either treatment alone. None of the treatments impaired fruit quality. Integrating the use of UV-C treatment with biocontrol yeast has potential as an effective method to control postharvest decay of melon.

As lead is one of the most hazardous heavy metals in river ecosystem, the influence of exogenous lead pollution on enzyme activities and organic matter degradation in the surface of river sediment with high moisture content were studied at laboratory scale. The dynamic changes of urease, catalase, protease activities, organic matter content, and exchangeable or ethylenediaminetetraacetic acid (EDTA)-extractable Pb concentration in sediment were monitored during different levels of exogenous lead infiltrating into sediment. At the early stage of incubation, the activities of catalase and protease were inhibited, whereas the urease activities were enhanced with different levels of exogenous lead. Organic matter content in polluted sediment with exogenous lead was lower than control and correlated with enzyme activities. In addition, the effects of lead on the three enzyme activities were strongly time-dependent and catalase activities showed lower significant difference (P < 0.05) than urease and protease. Correlations between catalase activities and EDTA-extractable Pb in the experiment were significantly negative. The present findings will improve the understandings about the ecotoxicological mechanisms in sediment.

The novel catalysts of Mn/Ti-doped carbon xerogel (CX) were synthesized for efficient degradation of microcystin-LR (MC-LR) in the water surface discharge plasma reactor. The degradation efficiency of 79.7 % was obtained in 6 min with 0.5 wt% Ti impregnation of CX, and it would be increased with higher amount of Ti. In particular, Mn-doped CX resulted in larger mesoporous particle diameter and higher porosity in the matrix, and thereby, the highest efficiency of 88.6 % was achieved for CX-Ti-Mn. The possible degradation pathway of MC-LR was elucidated on the basis of the LC-MS analysis. It demonstrated that Adda chain was cleaved from the MC-LR cyclic peptide by OH radical attack after plasma discharge in the presence of catalysts, and the generated nontoxic products can be further easily degraded in the biological treatment. Therefore, Mn/Ti-doped carbon xerogel is promising as the catalyst for the improvement of MC-LR degradation in the water surface discharge plasma reactor.

Microbial control agents offer alternatives to chemical pest control, as they can be more selective than chemical insecticides. The present study evaluates the mosquito larvicidal and pupicidal potential of fungus mycelia using ethyl acetate and methanol solvent extracts produced by Aspergillus terreus against Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti. The A. terreus mycelia were extracted after 15 days from Sabouraud dextrose broth medium. The ethyl acetate extracts showed lethal concentration that kills 50 % of the exposed larvae (LC₅₀) and lethal concentration that kills 90 % of the exposed larvae (LC₉₀) values of the first, second, third, and fourth instar larvae of An. stephensi (LC₅₀ = 97.410, 102.551, 29.802, and 8.907; LC₉₀ = 767.957, 552.546, 535.474, and 195.677 μg/ml), Cx. quinquefasciatus (LC₅₀ = 89.584, 74.689, 68.265, and 67.40; LC₉₀ = 449.091, 337.355, 518.793, and 237.347 μg/ml), and Ae. aegypti (LC₅₀ = 83.541, 84.418, 80.407, and 95.926; LC₉₀ = 515.464, 443.167, 387.910, and 473.998 μg/ml). Pupicidal activity of mycelium extracts was tested against An. stephensi (LC₅₀ = 25.228, LC₉₀ = 140.487), Cx. quinquefasciatus (LC₅₀ = 54.525, LC₉₀ = 145.366), and Ae. aegypti (LC₅₀ = 10.536, LC₉₀ = 63.762 μg/ml). At higher concentration (500 μg/ml), mortality starts within the first 6 h of exposure. One hundred percent mortality occurs at 24-h exposure. The overall result observed that effective activity against selected mosquito larvae and pupae after 24 h was a dose and time-dependent activity. These ensure that the resultant mosquito population reduction is substantial even where the larvicidal and pupicidal potential is minimal. The FTIR spectra of ethyl acetate extract reflect prominent peaks (3448.32, 3000.36, 2914.59, 2118.73, 1668.21, 1436.87, 1409.02, 954.33, 901.13, and 704.67 cm⁻¹). The spectra showed a sharp absorption band at 1314.66 cm⁻¹ assigned to wagging vibration of the C–H group. The band at 1023.59 cm⁻¹ developed for C–O and C=N, respectively, and was commonly found in carboxylic acid and amine groups. GC–MS analysis of ethyl acetate extracts showed the presence of six compounds, of which the major compounds were identified as n-hexadecanoic acid (15.31 %) and methyl 12,15-octadecadienoate (31.989 %), based on their peak molecular weight. The HPLC analysis result highlights that the A. terreus ethyl acetate extract was compared with pure n-hexadecanoic acid which resulted in similar retention time of 19.52 and 19.38, respectively. Thus, the active compound produced by this species would be more useful against vectors responsible for diseases of public health importance. This is the first report on mosquito larvicidal and pupicidal activity of ethyl acetate extract produced by A. terreus species.

Phototrophic microorganisms disfigure the surfaces of different types of stone. Stone structure is damaged by the activity of photoautotrophic and other microorganisms. However, to date few, investigations have been undertaken into the relationship between microorganisms and the properties of different types of marble. In this study, biological activity of photoautotrophic microorganisms on three types of marble (Yatagan White, Giallo Anticato and Afyon White) was investigated under laboratory conditions over a short period of time. The three types of marble supported the growth of phototrophic microbial communities on their outer and inner layers, turning their original colour from white to a yellowish green colour. The porosity of the marble types facilitated filamentous microbial growth in the presence of water. Scanning electron microscope analysis revealed the accumulation of aggregates such as small spherical, fibrillar, calcified globular bodies on the inner surfaces of the marbles. This suggests that the microscopic characteristics of particular marble types may stimulate the growth of certain types of microorganisms.

Intensive lignite and glass sand mining and industrial processing release waste which may contain elements hazardous to the aquatic ecosystem and constitute a potential risk to human health. Therefore, their levels must be carefully controlled. As a result, we examined the effects of sewage on the aquatic Fontinalis antipyretica moss in the Nysa Łużycka (lignite industry) and the Kwisa Rivers (glass sand industry). The Nysa Łużycka and the Kwisa Rivers appeared to be heavily polluted with As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn, which were reflected in the extremely high concentration of these elements in F. antipyretica along the studied watercourses. In the Nysa Łużycka, trace element composition in the moss species is affected by lignite industry with accumulation in its tissues of the highest concentrations of Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn, while samples from the Kwisa sites influenced by glass sand industry revealed the highest concentrations of As, V and Fe. The principal component and classification analysis classifies the concentration of elements in the aquatic F. antipyretica moss, thus enabling the differentiation of sources of water pollution in areas affected by mining industry.