Natural radioactivity in various surface waters in stanbul, Turkey

Gross-α and gross-β, activities of eight well and five tap water samples taken in stanbul were determined. Ra²²⁶, Rn²²², Pb²¹⁴, Bi²¹⁴, K⁴⁰, Cs¹³⁷ activity concentrations in four lake, four sea water, one snow and one rain water samples were also analyzed in order to determine their radioactivity. The results obtained showed that, in general, natural activities in drinking water samples did not exceed WHO and ITS guidelines. In sea and lake water, four samples were over WHO and TSI guidelines. Concentrations ranging from 0.007 to 0.04 Bq l⁻¹ and from 0.02 to 0.1 Bq l⁻¹ were observed for drinking water and the gross-α and gross-β activities, respectively. For all samples the gross-β activities were higher than the corresponding gross-α activities. In order to evaluate the annual effective dose equilavent of ingestion of these waters, a conservative dosimetric calculation was carried out using dose conversion factor suggested by the ICRP. An average annual effective dose equivalent of 0.84 μSv y⁻¹ for Ra²²⁶ was calculated.     

Survey of volatile halogenated organics (VHO) in Italy: Levels of VHO in drinking waters, surface waters and swimming pools

A survey undertaken in Italy (Emilia-Romagna region) has shown that Volatile Halogenated Organics (VHO) are present in many water samples; analysis has been performed by static head-space gas chromatographic technique.In drinking water samples low levels of pollution have become evident before any treatment, while after chlorination with sodium hypochlorite, or chlorine as a gas, VHO have appeared, almost exclusively as trihalomethanes (THM), sometimes at fairly high levels (max = 41.8 μg l⁻¹).Surface water samples have been collected every other month in one year, and have shown different levels of contamination; in most cases VHO (mainly chlorinated solvents) appeared just as traces, seldom at high concentration (max = 263 μg l⁻¹).Swimming pool samples have shown the high levels of contamination (max = 177.4 μg l⁻¹), mainly due to THM, as a consequence of chlorination with sodium hypochlorite.As a matter of fact, it has become evident that VHO pollution is wide-spread in every kind of water; while contamination of surface waters can only involve environmental and aquatic life, contamination especially of drinking waters, and also of swimming pool waters must be controlled as it can directly act on human health.     

Some elements comprising particulate matter during summer in waters of various environments in British Columbia, Canada

Multi-elemental traces comprising particulate matter in natural water collected during summer in 1978 and 1979 from British Columbia, Canada, were analyzed by α-particle excited X-ray fluorometry. Common elements from all waters examined were Si, Cl, Ca and Fe. The similarity of their distribution in different aquatic environments was statistically analyzed. They were distributed homogeneously in the marine environment but heterogeneously in the freshwater environments. No heavy metals concerned with the environmental standards were detected for all waters examined.     

CFD simulation and optimization of the ventilation for subway side-platform

To obtain the velocity and temperature field of subway station and the optimized ventilation mode of subway side-platform station, this paper takes the evaluation and optimization of the ventilation for subway side-platform station as main line, builds three dimensional models of original and optimization design of the existed and rebuilt station. And using the two-equation turbulence model as its physics model, the thesis makes computational fluid dynamics (CFD) simulation to subway side-platform station with the boundary conditions collected for simulation computation through field measurement. It is found that the two-equation turbulence model can be used to predict velocity field and temperature field at the station under some reasonable presumptions in the investigation and study. At last, an optimization ventilation mode of subway side-platform station was put forward.     

Endotoxin and β(1→3)-Glucan in House Dust and the Relation with Home Characteristics: A Pilot Study in 25 German Houses

Abstract Residential microbial exposure has been suggested to be involved in the development of asthma. This paper describes bacterial endotoxin and mold β(1→3)-glucan levels in house dust and the relationship to selected home characteristics. Dust was sampled from mattresses and living room and bedroom floors of 25 houses in Germany. Endotoxin and β(1→3)-glucan levels ranged from 200-48,600 EU/g dust (100-32,900 EU/m² sampled surface) and 182-3,507 μg/g (157-3,652 μg/m²), respectively. Bio-contaminant levels were highest on living room floors and lowest in mattresses. Dust, endotoxin and β(1→3)-glucan levels were 2–3 times higher on living room floors of centrally heated houses built after 1970 compared to older individually heated houses. This was not found for mattresses and bedroom floors. No associations between biocontaminant levels and other selected home characteristics (temperature, relative humidity, damp spots and insulation of windows) were found. β(1→3)-glucan levels were associated with total culturable fungi (per m²) in house dust, as well as with the fungal genus Alternaria (per g dust and per m²). In conclusion endotoxin and β(1→3)-glucan were readily detectable in house dust and significantly associated with heating system and/or age of the home.     

The activities of some fermentation enzymes in activated sludge and their relationship to enhanced phosphorus removal

A method to determine lactate, malate, β-HO-butyrate dehydrogenase and phosphotransacetylase activities in activated sludge was developed. The method was used to monitor two of the enzymes, which showed correlation with phosphorus removal in two activated sludge plants. The phosphorus removal capacity of the two plants showed different sensitivities to changes in the activities of β-HO-butyrate dehydrogenase and phosphotransacetylase. The reasons for this are discussed.     

Microbial Cell Wall Constituents in Indoor Air and their Relation to Disease

Abstract This presentation reviews the relation between damp buildings, mold growth and symptoms and disease among persons living or working in such buildings. Epidemiological studies on these relationships date back to 1924 and at present there are almost 30 large-scale investigations. There is an almost general concordance between studies on the relation between damp buildings and symptoms of the airways. Most of the studies show also a relation between symptoms and reported or measured mold growth. The symptoms reported are remarkably similar in the different studies: nose or throat irritation, wheezing, dry cough and fatigue. It is suggested that this symptom profile reflects a non-specific airways inflammation and that antigen-mediated allergy is rare. Regarding agents capable of inducing airways inflammation, data on bacterial endotoxin demonstrate a causal relationship, whereas information on another microbial wall agent - (1→3)-β-D-glucan - is suggestive but not conclusive of a causal relationship. From a practical point of view, dampness and previous mold growth represent conditions in buildings where renovation should be undertaken, particularly if there are symptoms of airways inflammation among the occupants.     

Characterization and pro‐inflammatory responses of spore and hyphae samples from various mold species

Mold particles from Aspergillus fumigatus, Penicillium chrysogenum, Aspergillus versicolor, and Stachybotrys chartarum have been linked to respiratory‐related diseases. We characterized X‐ray‐inactivated spores and hyphae fragments from these species by number of particles, morphology, and mycotoxin, β‐glucan and protease content/activity. The pro‐inflammatory properties of mold particles were examined in human bronchial epithelial cells (BEAS‐2B) and THP‐1 monocytes and phorbol 12‐myristate 13‐acetate (PMA)‐differentiated THP‐1. Spores from P. chrysogenum and S. chartarum contained some hyphae fragments, whereas the other preparations contained either spores or hyphae. Each mold species produced mainly one gelatin‐degrading protease that was either of the metallo‐ or serine type, while one remains unclassified. Mycotoxin levels were generally low. Detectable levels of β‐glucans were found mainly in hyphae particle preparations. PMA‐differentiated THP‐1 macrophages were by far the most sensitive model with effects in the order of 10 ng/cm². Hyphae preparations of A. fumigatus and P. chrysogenum were more potent than respective spore preparations, whereas the opposite seems to be true for A. versicolor and S. chartarum. Hyphae fragments of A. fumigatus, P. chrysogenum, and A. versicolor enhanced the release of metalloprotease (proMMP‐9) most markedly. In conclusion, species, growth stage, and characteristics are all important factors for pro‐inflammatory potential.     

Endotoxin,extracellular polysaccharides,and β(1‐3)‐glucan concentrations in dust and their determinants in four European birth cohorts: results from the HITEA project

Early‐life exposure to microbial agents may play a protective role in asthma and allergies development. Geographical differences in the prevalence of these diseases exist, but the differences in early‐life indoor microbial agent levels and their determinants have been hardly studied. We aimed to describe the early‐life levels of endotoxin, extracellular polysaccharides (EPS), and β(1‐3)‐glucans in living room dust of four geographically spread European birth cohorts (LISA in Germany, PIAMA in the Netherlands, INMA in Spain, and LUKAS2 in Finland) and to assess their determinants. A total of 1572 dust samples from living rooms of participants were analyzed for endotoxin, Penicillium/Aspergillus EPS, and β(1‐3)‐glucans. Information on potential determinants was obtained through questionnaires. Concentrations of endotoxin, EPS, and β(1‐3)‐glucans were different across cohorts. Concentrations of endotoxin and EPS were respectively lower and higher in INMA than in other cohorts, while glucans were higher in LUKAS2. Season of sampling, dog ownership, dampness, and the number of people living at home were significantly associated with concentrations of at least one microbial agent, with heterogeneity of effect estimates of the determinants across cohorts. In conclusion, both early‐life microbial exposure levels and exposure determinants differ across cohorts derived from diverse European countries.     

Determinants of house dust,endotoxin, and β‐(1→3)‐D‐glucan in homes of Danish children

Little is known about the geographic variation and determinants of bacterial endotoxin and β ‐(1,3)‐d ‐glucan in Danish house dust. In a population of 317 children, we: (i) described loads and concentrations of floor dust, endotoxin, and β‐(1→3)‐d ‐glucan and (ii) their correlations and (iii) assessed their determinants; (iv) Finally, we compared our findings with previous European studies. Bedroom floor dust was analyzed for endotoxin content by the kinetic limulus amoebocyte lysate assay and for β‐(1→3)‐d ‐glucan by the inhibition enzyme immunoassay. The parents answered questions regarding potential determinants. We found: geometric means (geometric standard deviations) 186 mg/m² (4.3) for dust; 5.46 × 10³EU/m² (8.0) and 31.1 × 10³EU/g (2.6) for endotoxin; and 142 μg/m² (14.3) and 0.71 × 10³ μg/g (7.3) for β‐(1→3)‐d ‐glucan. High correlations (r > 0.75) were found between floor dust and endotoxin and β‐(1→3)‐d ‐glucan loads, while endotoxin and β‐(1→3)‐d ‐glucan concentrations were moderately correlated (r = 0.36–0.41) with the dust load. Having a carpet was positively associated with dust load and with endotoxin and β‐(1→3)‐d ‐glucan concentrations. Pet keeping, dwelling type, and dwelling location were determinants of endotoxin concentrations. No other determinants were associated with β‐(1→3)‐d ‐glucan concentrations. Compared with other European studies, we found lower β‐(1→3)‐d ‐glucan loads and concentrations but higher endotoxin loads and concentrations suggesting a geographically determined different composition of Danish floor dust compared with other European regions.     

Stochastic modelling of mean monthly flows of Karasu River,in Turkey

Stochastic modelling of streamflows is vital for planning water resource systems. In this study, a stochastic model of the mean monthly streamflows at 2154 A?a?ιka?dariç Gauging Station on Karasu River was constructed. Studies were carried out using data from the water yearbooks published by chk later onEIE. The modelling procedure for streamflows with constant coefficient autoregressive moving average (ARMA) models was given in detail and indicated models were constructed. Analysis with streamflows at 2154 A?a?ιka?dariç Gauging Station showed that the autoregressive (AR) (1) model is the most appropriate model among the competing models. While selecting the most efficient model the Akaike information criterion (AIC) was used. The Port–Manteau test showed that residuals are white noise series. Using the AR(1) model, 100 synthetic series were generated and the time series generated were found to have the same statistical parameters (monthly mean, monthly standard deviation and autocorrelation) as historic time series within 95% confidence intervals.     

Escherichia coli contamination of the river Thames in different seasons and weather conditions

Contamination of public water ways with sewage represents a serious environmental and health risk. We monitored pollution of the river Thames by enumerating the indicator organism Escherichia coli. Samples were taken from a site in central London near Waterloo Bridge in different seasons. E. coli were quantified using a membrane filtration method, and correlated with the tidal variations of the river and meteorological data on rainfall and temperature. More frequent and severe incidents of pollution occurred in the autumn. Heavy rainfall resulted in sharp peaks of E. coli contamination that implies a potential increase of numbers of pathogenic micro‐organisms. Sixty percent of all samples were found to be in excess of the accepted upper limit of pollution set by European Union (EU) legislation for bathing water. This study demonstrated that frequent sewage pollution of the Thames results in high numbers of E. coli and incidents of detectable levels of pathogenic bacteria demonstrating the need for regular monitoring of bacterial pollution.     

The identification of highly chlorinated ethers and diethers in river sediment near an epichlorohydrin plant

In harbour sediment samples taken near an epichlorohydrin production plant, a series of highly chlorinated ethers and diethers were detected viz. three isomeric bis(dichloropropyl)ethers, several structurally closely related ethers with 9 carbon atoms (C₉ ethers), a number of C₁₂ ethers and diethers, and finally several C₁₅ ethers. The formation of this new class of ether compounds can be explained on the basis of the chemistry of the addition of HOCl to allylchloride. After initial addition of Cl⁻, a reactive intermediate is formed which may react with the product dichloropropanol, to give the C₆ ethers, or may polymerize with the starting compound allylchloride followed by reaction with the product, to give the C₉, C₁₂ and C₁₅ ethers.     

Analysis of dissolved microcystins in surface water samples from Kovada Lake, Turkey

Dissolved (extracellular) microcystin (MC) concentrations were determined at 3 sampling stations on Lake Kovada, Turkey. The dominant species of cyanobacteria found in August and September of 2006 were Microcystis aeruginosa, Synechococcus sp., Phormidium limosum, Phormidium formosa and Planktothrix limnetica. MC concentrations in water were measured by ELISA and MC variants were examined by HPLC-PDA. Quantitative analysis by HPLC indicated that five MC variants (MC-LR, -RR, -LA, -LW, -LF) were identified in water samples from Kovada Lake. The maximum concentration of dissolved MC-LW was 98.9 µg l^− 1 in October. MC-LR was only detected in May at a concentration of 0.5 µg l^− 1. The cross reactivity of the antibody (MC10E7) to variants such as MC-LA MC-LW & MC-LF was low. Hence the results determined by ELISA were lower than those determined by HPLC in September and October samples due to differences in the specificity of the antibody to MC variants. Total extraceullar MCs was quantified by ELISA and ranged from 0.73 to 48.5 µg MC-LR equivalents l^− 1, which in some cases exceeded the WHO provisional Guideline Value for MC-LR in drinking water. This study confirms that the lakes of Turkey should be monitored for toxic cyanobacteria and for MCs to avoid or reduce the potential exposure of people to these health hazards.     

Direct photolysis of estrogens in aqueous solutions

Direct photolysis of two estrogens 17beta-estradiol (E2) and estrone (E1) in aqueous solutions radiated by UV-light and UV-Vis-light was studied preliminarily. The results suggest that the photolysis of E2 in aqueous solutions occurs under irradiation with UV disinfection lamp (lambda = 254 nm, 30 W), while E1 can also undergo photolysis under irradiation with a high-pressure mercury lamp (lambda > or = 365 nm, 125 W). The photolysis reactions of E2 and E1 at the concentration of 3.0-20 mgl(-1) in aqueous solutions were all in accordance with pseudo-first-order law. The photolysis rate of estrogens in aqueous solutions reached the lowest value at pH approximately 5.0, while the highest at pH 8.0 over the range of 2.0-8.0. The higher the initial concentration of the two estrogens, the lower the rate of photolysis.     

Azolla–Anabaena's behaviour in urban wastewater and artificial media – Influence of combined nitrogen

The results of using the nitrogen fixing symbiotic system Azolla–Anabaena to improve the quality of treated urban wastewater, particularly on what concerns phosphorus removal efficiencies (40–65%), obtained in continuous assays performed during the past few years and presented earlier, were very promising. Nevertheless, the presence of combined nitrogen in some wastewaters can compromise the treatment efficiency. The main goal of this work was to compare plants behaviour in wastewater and in mineral media with and without added nitrogen.Azolla filiculoides's specific growth rates in wastewater and in mineral media without added nitrogen or with low nitrate concentration were very similar (0.122 d⁻¹–0.126 d⁻¹), but decreased in the presence of ammonium (0.100 d⁻¹). The orthophosphate removal rate coefficients were similar in all the growth media (0.210 d⁻¹–0.232 d⁻¹), but ammonium removal rate coefficient in wastewater was higher (0.117 d⁻¹) than in mineral medium using that source of nitrogen (0.077 d⁻¹).The ammonium present in wastewater, despite its high concentration (34 mg N L⁻¹), didn't seem to inhibit growth and nitrogen fixation, however, in mineral media, ammonium (40 mg N L⁻¹) was found to induce, respectively, 18% and 46% of inhibition.     

Associations between evaporative cooling and dust‐mite allergens,endotoxins, and β‐(1 → 3)‐d‐glucans in house dust: A study of low‐income homes

Recent work suggests that evaporative coolers increase the level and diversity of bioaerosols, but this association remains understudied in low‐income homes. We conducted a cross‐sectional study of metropolitan, low‐income homes in Utah with evaporative coolers (n = 20) and central air conditioners (n = 28). Dust samples (N = 147) were collected from four locations in each home and analyzed for dust‐mite allergens Der p1 and Der f1, endotoxins, and β‐(1 → 3)‐d ‐glucans. In all sample locations combined, Der p1 or Der f1 was significantly higher in evaporative cooler versus central air conditioning homes (OR = 2.29, 95% CI = 1.05‐4.98). Endotoxin concentration was significantly higher in evaporative cooler versus central air conditioning homes in furniture (geometric mean (GM) = 8.05 vs 2.85 EU/mg, P < .01) and all samples combined (GM = 3.60 vs 1.29 EU/mg, P = .03). β‐(1 → 3)‐d ‐glucan concentration and surface loads were significantly higher in evaporative cooler versus central air conditioning homes in all four sample locations and all samples combined (P < .01). Our study suggests that low‐income, evaporative cooled homes have higher levels of immunologically important bioaerosols than central air‐conditioned homes in dry climates, warranting studies on health implications and other exposed populations.     

A toxicity warning monitor using the weakly electric fish, Gnathonemus petersi

A technically simple fish monitor was developed using the weakly electric fish, Gnathonemus petersi, as the test organism. The test system consists of a plexiglass test chamber (21., 27°C) with a flow-through of 4–5 times the chamber volume per hour. The spontaneous electric organ discharges (EOD) are recorded as activity signals. EODs, which have a potential of about 500 mV, last 0.3 ms and they can be converted to computer-compatible signals by a simple amplifier. The EOD-activity is analyzed by a low-cost desk-top computer. Two different modes of analysis which represent two levels of response sensitivity, are possible either alternatively or simultaneously. The toxicity response of Gnathonemus petersi was measured in experiments with the toxicants Hg²⁺, Cu²⁺, NaAsO₂ and CN⁻. The sensitivity to acutely toxic concentrations was found to be as high as that of trout or minnows.     

Periphytic oxygen production in outdoor experimental channels

The contribution of periphytic oxygen was quantified in outdoor artificial streams. A factorial design was employed to determine the effect of stream velocity and light on periphytic growth, measured as chlorophyll α. Results showed that periphytic oxygen production can be estimated by the equation: =0.91 × 10⁻³ × Light Intensity (1x) + 0.061 for light intensities to 5000 ft-candles (53,800 lx). Stream velocity was found to be statistically insignificant in affecting oxygen production, but was a factor in periphyton accural and species composition. Gross oxygen production exceeded respiration by a factor of three.