One of the problems to affect Portland cement matrices is low resistance to aggressive agents, due principally to the presence of a high content of portlandite in the hydrated cements. Pozzolanic materials have, for decades, played an important role in improving the durability of cement-based materials. This work studies the behaviour of cement mortar matrices blended with 10% calcined paper sludge (source for metakaolin, MK) and exposed to different environmental conditions (marine and tableland environments). The results obtained using X-ray diffraction and scanning electron microscopy/energy-dispersive X-ray analyser techniques show that the ions present speed of different penetration as well as various phases and/compounds in the matrices following exposure over 1 year.

The presence of polylcyclic aromatic hydrocarbons (PAHs) in surface sediments of Barigui River was investigated. PAHs are considered highly toxic and persistent compounds because of their structure. They originate from incomplete combustion of fossil fuels or biomass. The Barigui River crosses the metropolitan region of Curitiba, and some regions are highly polluted and located near the possible sources of pollution. The results showed that concentrations of total PAHs ranged from 44.6 to 880.2 ng g⁻¹, and the highest values were found at the sites previously investigated and identified as critically polluted. At sites located away from the traffic and possible pollution sources, the total PAHs was lower, 44.6 ng g⁻¹. Due to their hydrophobic character, sediments with high silt and clay content retain greater amounts of PAHs. The granulometric composition of the sediments revealed that most of them are composed basically by silt and clay, and those samples showed high concentration of PAHs. The organic carbon content also confirms this observation. The other sites investigated showed a high capacity to adsorb hydrophobic compounds mainly due to the granulometric composition and organic matter that adsorb poorly water soluble compounds. Finally, we found that the main sources of PAHs are petrogenic; however, at some sites, it is hard to confirm this pattern, and possibly, a mixture of the source would be more appropriate.

A study was conducted to determine nitrogen budget and ammonia volatilization in Japanese paddy fields supplemented with liquid cattle waste (LCW). A series of four, 2 x 10 m experimental plots was established in a paddy field with silty clay soil planted with forage rice (Oryza sativa L.). In addition to 195 kg N ha⁻¹ of chemical or compost-based basal fertilizer, LCW was applied as an additional fertilizer at total nitrogen rates of 0, 255, 255, and 405 kg N ha⁻¹ to the four plots C195, T450-1, T450-2, and T600, respectively. The mass balance showed that after application of LCW, 32-39% of total input nitrogen was assimilated into aboveground parts of rice plants, 11-15% leached downward, 2.5-4.0% was lost via ammonia volatilization, 1.6-5.1% was retained in roots or was adsorbed onto soil, and approximately 30-40% was lost via denitrification. Compared to animal waste slurries applied to unsaturated soils, nitrogen loss via ammonia volatilization was relatively lower, probably due to the dilution effect of floodwater. Nitrogen loss via denitrification was markedly higher in areas where LCW was applied compared to areas without LCW application. On the other hand, nitrogen leaching downwards represented a substantial loss and may be an environmental concern. However, after LCW application only, the ammonium ion was detected, at a maximum nitrogen concentration of 11.4 mg L⁻¹. In this system, therefore, nitrogen has a different fate to that in animal waste slurries applied to unsaturated soil. In that situation, the major nitrogen form in leaching water is nitrate nitrogen, which moves readily into groundwater.

Background, aim and scope The use of sodium hypochlorite (HYP) in viticulture results in effluents which are contaminated with halogenated substances. These disinfection by-products (DBPs) can be quantified as group parameter 'adsorbable organic halogens' (AOX) and have not been determined in effluents of viticulture yet. The substances that are detected as AOX are unknown. The AOX can be composed of harmless substances, but even toxic contaminants. Thus, it is impossible to assess ecological impacts. The aim of this study is to determine the quantification of AOX and DBPs after the use of HYP. This will be helpful to reduce environmental pollution by AOX. Materials and methods The potential of HYP to generate AOX was determined in laboratory-scale experiments. Different model solutions were treated with HYP according to disinfection processes in viticulture and conditions of AOX formation in effluents were simulated. AOX were quantified using the flask-shaking method and identified DBPs were investigated by gas chromatography-mass spectrometry. Results Treatment with HYP resulted in the formation of AOX. The percentage conversion of HYP to AOX was up to 11%. Most important identified DBPs in viticulture are chloroform, dichloroacetic acid and trichloroacetaldehyde. In addition, the formation of carbon tetrachloride (CT), 1,1,1-trichloropropanone, 2,4-dichlorobenzoic acid and 2-chloro-/2,4-dichlorophenylacetic acid was investigated. It was demonstrated that reaction temperature, concentration of HYP and type of organic matter have important influence on the formation of chlorinated DBPs. Discussion The percentage conversion of HYP to AOX was similar to other published studies. Although a correlation of single compounds and AOX is difficult, chloroform was the predominant AOX. Generation of the volatile chloroform should be avoided due to possible adverse effects. The generation of dichloroacetic acid is of minor importance on account of biodegradation. Trichloroacetaldehyde and 1,1,1-trichloropropanone are weak mutagens and their formation should be avoided. Conclusions The generation of AOX and chlorinated DBPs can be minimised by reducing the concentrations of the organic materials in the effluents. The removal of organic matter before disinfection results in a decreased formation of AOX. HYP is an effective disinfectant; therefore, it should be used at low temperatures and concentrations to reduce the amount of AOX. If possible, disinfection should be accomplished by the use of no chlorine-containing agents. By this means, negative influences of HYP on the quality of wine can also be avoided. Recommendations and perspectives Our results indicate that HYP has a high potential to form AOX in effluents of viticulture. The predominant by-products are chloroform, dichloroacetic acid and trichloroacetaldehyde. In further research, wastewaters from a winery and the in- and outflows of two sewage treatment plants were sampled during vintage and analysed. These results will be discussed in a following paper.

Gaseous phosphine (PH₃) in the inshore atmosphere was observed from October 2005 to August 2006 at a coastal site of the Yellow Sea in China. The concentration of PH₃ ranged from 0.01 to 14.86 ng m⁻³ with an average of 1.14 ng m⁻³. The concentration showed a diurnal variation in PH₃ with the peak occurring at morning and the lowest point at noon. An obvious seasonal variation of atmospheric PH₃ was found, with the PH₃ levels in the summer higher than those in the winter. The PH₃ levels in the atmosphere were apparently affected by temperature, radiation, sources, and other meteorological factors. The data indicate that PH₃ can be transported between the terrestrial and inshore atmosphere of Qingdao and the Yellow Sea or the East China Sea in both directions. The study increases evidence that PH₃ participates within the global biogeochemical phosphorus cycle in P transport from land and inshore waters to the sea where commonly P is scarce and where PH₃ inflow could be of important.

We tested the hypothesis that there would be measurable losses of phosphorus (P) from surficial sediments of Upper Klamath Lake (UKL), Oregon, if sediments were a source of P during an algal bloom. We compared concentrations of total and forms of P at various depths in cores collected before and after the onset of a large Aphanizomenon flos-aquae bloom. Concentrations of inorganic P were determined in extraction solutions of MgCl₂ (1 M, pH 8), citrate-dithionite-bicarbonate, and 1 M HCl. Sediments below 2 cm were dominated by residual P which is defined as total P minus inorganic P. During the study period, data from the top 2-cm of sediment indicated (a) significant decrease in total P concentration, primarily associated with iron oxyhydroxides at one site, and (b) significant increase in total P concentration associated with residual P at a second site. Data from two other sites indicated no net changes in concentrations of total P.

The influence of cadmium on growth, cadmium accumulation, composition, and content of glucosinolates was investigated in Arabidopsis thaliana after 4 weeks of growth in hydroponics. Accumulation of 3,820 and 321 μg Cd g⁻¹ dry weight in the roots and leaves of A. thaliana, respectively, exposed to 50 μM Cd. Cadmium treatment significantly decreased the total concentration of glucosinolates both in the leaves and roots. Cd-induced alteration of total glucosinolate content in the roots was mainly due to the decrease of indolyl-glucosinolates. In the Cd treatment leaves, significant decreases were, respectively, detected for glucoibervirin and 4-methoxyglucobrassicin (P < 0.01), while other glucosinolate levels did not decrease significantly. In response to cadmium, the three indolyl-glucosinolates all showed significant decreases in the roots. The distinctive influence of cadmium on glucosinolate profiles in Cd-sensitive A. thaliana may be of great ecological importance, decreasing the resistance to phytophage attack. Taken together, our data is discussed in relation to jasmonic acid and salicylic acid as possible molecules that modulate the alteration of glucosinolate profiles in response to cadmium. The similar effects of Cd treatment on the levels of individual glucosinolates in leaves and roots were observed at higher-concentration cadmium treatment (100 μM Cd).

In this study, a high-rate fibre filter was used as a pre-treatment to stormwater in conjunction with in-line flocculation. The effect of operating the fibre filter with different packing densities (105, 115 and 125 kg/m³) and filtration velocities (20, 40, 60 m/h) with and without in-line flocculation was investigated. In-line flocculation was provided using 5, 10 and 15 mg/L of ferric chloride (FeCl₃·6H₂O). The filter performance was studied in terms of pressure drop (ΔP), solids removal efficiency, heavy metals (total) removal efficiency and total organic carbon (TOC) removal efficiency. It is found that the use of in-line flocculation at a dose of 15 mg/L improved the performance of fibre filter as measured by turbidity removal (95%), total suspended solids reduction (98%), colour removal efficiency (99%), TOC removal (reduced by 30-40 %) and total coliform removal (93%). The modified fouling index reduced from 750-950 to 12 s/L² proving that fibre filter can be an excellent pre-treatment to membrane filtration that may be consider as post-treatment. The removal efficiency of heavy metal was variable as their concentration in raw water was small. Even though the concentration of some of these metals such as iron, aluminium, copper and zinc were reduced, others like nickel, chromium and cadmium showed lower removal rates.

The effect of nickel (Ni) excess on selected aspects of chamomile (Matricaria chamomilla L.) metabolism was studied. Water-soluble Ni represented 27%, 46%, and 47%, and the methanol-soluble fraction 54%, 70%, and 88% of total shoot Ni content after 10 days of treatments with 3, 60, and 120 μM Ni, respectively. “Intra-root” Ni content represented 72% (3 μM), 96% (60 μM), and 78% (120 μM) of total root Ni. Leaf rosettes treated with 120 μM contained 137 μg Ni g⁻¹ DW after 10 days of treatment. The highest Ni concentration particularly affected the content of mineral nutrients (e.g., decrease of K and increase of Fe) and activity of selected antioxidative enzymes (increase of ascorbate peroxidase and guaiacol peroxidase activities). Malondialdehyde accumulation was not influenced (measured in methanol extracts). Among 17 detected free amino acids, accumulation of histidine, proline, methionine, and cysteine was most distinct in the leaf rosettes and/or roots, indicating their involvement in Ni detoxification. Lower Ni toxicity in comparison to previously tested metals is also discussed.

This work investigates the solar heterogeneous photocatalytic degradation of three commercial acid dyes: Blue 9 (C.I. 42090), Red 51 (C.I. 45430), and Yellow 23 (C.I. 19140). TiO₂ P25 from Degussa was used as the photocatalyst. The dyes were completely degraded within 120 min of treatment in the following increasing order of removal rate: Blue 9 < Yellow 23 < Red 51. The photocatalytic color removal process was well described by a two-first-order in-series reaction, followed by another first-order reaction. Photolytic experiments showed that this process is quite inefficient and highly selective towards Red 51 only. The dyes' solution was completely decolorized and organic matter removals up to 99% were achieved with photocatalysis. The lack of selectivity and the possibility of using solar light to excite the photocatalyst are promising results regarding the feasibility of this technology.