The effects of six phosphate (P) fertilizers in mobilizing and immobilizing water-soluble lead (Pb) were determined in a contaminated soil (Alfisol from Shaoxing) from China and four Australian soils (an Oxisol from Twonsville Queensland and three South Australian soils from Cooke Plains (Typic Palexeralf)), Inman Valley (Vertisol), and Two Wells (Natric Palexeralf). The fertilizers tested were single superphosphate (SSP), triple superphosphate (TSP), monoammonium phosphate (MAP), diammonium phosphate (DAP), monocalcium phosphate (MCP), and dicalcium phosphate (DCP) to produce an initial P concentration of 1,000 mg/L. The Chinese soil contained 16,397 mg/kg total Pb, but the Australian soils were uncontaminated. The four Australian soils were each spiked with 1,000 mg Pb/kg soil (as Pb(NO3)2) and incubated for a month. Single superphosphate treatments decreased total soluble Pb in soil solution to 2-14 % of those of the nil-P (0P) treatment in the four Pb-spiked soils and to 48 % in the Chinese Pb-contaminated soil. The DAP treatment followed by the MAP treatment greatly increased the total soluble Pb in soil solution up to 135-500 % of the 0P treatment, except in the Two Wells soil. MCP could decrease the total soluble Pb in Cooke Plains, Inman Valley, Shaoxing, and Two Wells soils while increase it in the Queensland soil; DCP decreased the total soluble Pb in Cooke Plains and Queensland soils while increased it in the Shaoxing and Inman Valley soils. There were close relationships between the total soluble Pb, total soluble Al, and total soluble Fe in the water extracts of each. Soluble Al and Fe ions in soil solution increased soluble Pb concentrations. We conclude that not all phosphate fertilizers immobilize Pb in soils equally well. SSP and TSP are excellent Pb-immobilizing fertilizers, while MAP and DAP are strong Pb-mobilizing fertilizers. MCP and DCP are either Pb-immobilizing fertilizers or Pb-mobilizing fertilizers depending on their reactions with individual soils. © 2013 Springer Science+Business Media Dordrecht.

Laboratory experiments were carried out to determine the effects of exposure to different concentrations of As, Hg, Sb and Se on photosynthetic and respiratory rates and on photosynthetic efficiency in the aquatic bryophyte Fontinalis antipyretica Hedw. Specimens of the moss, collected from a clean site, were incubated in solutions of As, Hg, Sb and Se (at concentrations ranging from 0.1 μg l-1 to 10,000 μg l-1) for up to 22 days. The photosynthetic and respiratory rates were then determined by the light/dark bottle technique, and the photosynthetic efficiency was measured by the saturation pulse method. Although different responses were observed in relation to the concentration of the elements, clear responses in net photosynthesis and photosynthetic efficiency were generally only observed in the moss exposed to the highest concentrations of these elements in solution. Mercury was apparently the most toxic of the elements studied. Net photosynthesis and photosynthetic efficiency were also related to tissue concentrations of these elements in the moss. Despite the higher toxicity of Hg, this element can be accumulated at high concentrations in moss, probably at extracellular sites. For Sb, the same tissue concentration had very different physiological effects depending on the initial concentration to which the moss was exposed in solution. Temporal trends in chlorophyll fluorescence were more stable than trends in net photosynthesis. The respiratory rate was very variable and was not clearly related to the concentration of elements in solution or in moss tissues. © 2013 Springer Science+Business Media Dordrecht.

Average and 75 % biochemical oxygen demand (BOD) in the Yamato-gawa River, Japan, in 1963 were smaller than the criteria determined in 1970 (5 mg l⁻¹); however, they were deteriorated up to 22–32 mg l⁻¹ in 1970. The deterioration was caused by the population increase and economic and urban development. The national-level regulations on ambient water quality and pollutant discharge have been established in 1970. Municipal wastewater is the major contributor in pollutant discharges in the river basin. Estimated BOD discharge (PD(BOD)) in the river basin reduced to the level of 1963 in 2000; however, average and 75 % BOD were more than the criteria. Analysis on the relationship between BOD and PD(BOD) resulted in the five phases in 1963–2009. The equilibrium conditions changed from phase I to II because of the perturbation caused by the excess BOD discharge, self-correcting mechanisms were found in phase III, and equilibrium conditions changed from phase III to IV and V. The comparison of estimated BOD based on pollutant generation (PG) without measures and monitored BOD represented the following situations in 47 years: (1) It took several years before the effects of centralised WWTPs were observed, (2) PD(BOD) was less than 35 t-BOD day⁻¹ for the linear relationship of PD(BOD) and BOD, and (3) combined effects of wastewater treatment, river water purification facilities and soft measures were estimated to be about 10 mg-BOD l⁻¹ in 2010.

Many airborne and soil-borne nanoparticles (NPs) can enter plants, which are the primary producers in the food chain; recently, studies on the genotoxic effects of NPs on plants are emerging. In the present study, the phytotoxic and genotoxic effects of ZnO and CuO NPs on buckwheat (Fagopyrum esculentum) seedlings were estimated. The inhibition of root growth and biomass at the tested concentrations of NP suspensions and dissolved free ion suspensions were compared. Changes in root morphological features and localization of NPs inside the root epidermis cells were observed. Growth of root treated with ZnO NPs (84.9 and 89.6 %) and CuO NPs (75.4 and 80.1 %) at 2,000 and 4,000 mg L -1, respectively, was decreased significantly than control. The root morphological features and NP incorporation into the root epidermal cells at a high dose of NP showed completely different patterns compared to those for the controls. Through random amplified polymorphic DNA assays for comparison of the effect of ZnO and CuO NPs on DNA stability, it was shown as different DNA polymorphisms at 2,000 and 4,000 mg L-1 of ZnO and CuO NPs, compared to those for controls. Our results provide the first clue to the genotoxic effects of ZnO and CuO NPs on early growth of edible plants such as buckwheat. © 2013 Springer Science+Business Media Dordrecht.

The connection between hydrocarbon biodegradation and surface-active substance production has attracted great interest in recent years. Pseudomonas fluorescens PT, isolated from a biotrickling filter, was not only able to degrade α-pinene but also to use it as a carbon source to produce a surface-active substance. Response surface methodology analysis showed that the optimal medium composition was K⁺, 69.8; Mn²⁺, 65.1; and NH₄ ⁺, 482.5 mg L⁻¹, at which the surface tension of the medium was reduced to 40.7 mN m⁻¹ after 36 h. Based on compositional analysis and information on α-pinene metabolism, the purified compound was identified as perilla acid. The surface-active properties of the purified compound were more stable than those of a synthetic surfactant, and it had lower ecological toxicity to Chlorella vulgaris. The naphthalene solubility and mass transfer of α-pinene were enhanced almost twofold by the surface-active substance (at its critical micelle concentration). The results suggested that the PT strain may be promising for generating surface-active substances with improved physiochemical properties for a wide range of applications in environmental remediation.

Robust and cheap, biofiltration is one of the most used methods for the biological treatment of industrial gaseous odours and VOCs emissions. The chemical, physical and microbial properties, as well as the economical impact of 11 organic and inorganic packing materials potentially suitable for biofiltration, have been investigated in order to select the most relevant for the treatment of rendering gaseous emissions. Fibrous materials such as peat and coconut fibres are predisposed to compaction. Moreover, according to their low expected running period, their implementation remains expensive, such as activated carbon which induce overweening costs (>100,000€ an -1 for the treatment of 40,000 m3 h-1 with a 60-s empty bed gas residence time). Considering economical aspects, physico-chemical and biological properties, pines barks, composted wood mulch and expanded schist seem fit for this application. The performance of these materials was therefore investigated in a pilot-scale study conducted on a rendering site. According to its appropriate pH (8.62) and water-holding capacity (1.41 g g-1) and its highest nutrients content and colonization at the biofilter start-up (93 g of ATP m-3, 29.10 13 CFU m-3), composted would mulch show the best odour removal efficiency during the 134 days of operation. Performances ranged between 75 and 93 % for the treatment of odourous inlet load between 1.16 and 10.10·106 ouE m-3 h-1 with an empty bed gas residence time of 47 s. However, the pressure drop of the compost bed decreased, suggesting structural changes which may impact the performances in the long term. © 2013 Springer Science+Business Media Dordrecht.

The effectiveness of activated carbon sample (Carbonₑₓₚ) prepared by KOH chemical activation in hampering oligomerization of multicomponent adsorption was systematically examined. Anoxic (absence of molecular oxygen) and oxic (presence of molecular oxygen) adsorption isotherms of single-solute (2,4-dimethylphenol), binary solute (2-methylphenol/2,4-dimethylphenol), and ternary solute (phenol/2-methylphenol/2,4-dimethylphenol) were studied, using Carbonₑₓₚ and commercial granular activated carbon F400. Both binary solute adsorption and ternary solute adsorption on Carbonₑₓₚ indicated no impact of the presence of molecular oxygen on the adsorptive capacity. No significant differences between oxic and anoxic environment were noticed for any multicomponent adsorption systems, which indicated the effectiveness of Carbonₑₓₚ in hampering the oligomerization of phenolic compounds. On the other hand, in F400, which has lower microporosity and acidic functional groups, significant increases in the adsorptive capacity had been observed when molecular oxygen was present.

Acid mine drainage (AMD) has long been a significant environmental problem that impairs water resources in historic or current mining industries throughout the world. One of the methods using passive treatment system at low cost to remove metals from solution involves the use of clays. The ability of three different adsorbents (montmorillonite K-10, bentonite (NT-25), and hydrotalcite (HT)) to remove Fe and Mn from aqueous solutions and acid mine drainage samples has been studied at different optimized conditions such as pH, amount of adsorbent and contact time. Flame atomic absorption spectrometer (FAAS) was used for measuring Fe and Mn concentrations. Langmuir and Freundlich isotherms were applied and isotherm coefficients were computed. A kinectic study was also developed for HT using the first order, second order and intraparticle diffusion models. A great amount of clay (more than 100 mg) and also contact times higher than 60 min had also no influence in the adsorption capacity for all adsorbents. HT was found to be the best among the studied clays removing more than 90 % of Fe and Mn for all AMD samples investigated. Moreover, the maximum adsorption capacity was 63.7 mg Mn g⁻¹ HT and 666.7 mg Fe g⁻¹ HT.

Calcium dissolved deposition shows an unusual spatial structure in France, probably due to the contribution of southern air masses from Mediterranean Sea and Saharan desert. These masses are often loaded with terrigenous particles that contain carbonates. However, no precise relationship has been quantified between dissolved Ca and mineral dust deposition (MDD). The database of the French network RENECOFOR, gathering atmospheric deposition <0.45 mu m in 27 sites near forests during 18 years, was used to determine the non-sea-salt atmospheric deposition over France. This study (1) explores the relationship between dissolved components to decipher their origin in atmospheric deposition nearby forests and (2) tests the use of dissolved Ca and Mg as proxies for MDD. In the RENECOFOR database, non-sea-salt Ca (nssCa) preferentially deposited between May and August. MDD observed in RENECOFOR was synchronic with high nssCa deposition, particularly in June 2008, when air mass highly loaded with Saharan dust covered France. The dissolution of this mineral dust likely contributed to the nssCa deposition of this period and suggested a relationship between the depositions of nssCa and MDD. Then, MDD was specifically sampled with dissolved deposition in four sampling sites. Encouraging relationships were found between MDD and the depositions of nssMg and nssCa, suggesting that the latter could be used as a proxy for MDD in regions where it is not monitored, and in a retrospective approach in order to calculate nutrient fluxes.

N-Nitrosodimethylamine (NDMA) is recently defined as one of nitrogenous disinfection by-products with high carcinogenicity and can be frequently detected in finished water. The decomposition of NDMA in water using nanoscale zero-valent iron (NZVI) in the presence of aluminum and iron salts was investigated in this paper. The results showed that some salts can enhance the removal of NDMA by commercial NZVI in the order of Al(SO) >> AlCl > FeSO > NaSO ≈ NZVI alone, and the highest NDMA removal was 87.3 % in the presence of Al(SO). NDMA removal varied with the addition of Al(SO), NZVI dosage, initial NDMA concentration, solution pH, and temperature. The reduction of NDMA increased with the dosage of Al(SO) and NZVI, which follows a pseudo-first-order kinetics model. The removal of NDMA by NZVI was higher in acidic pHs than in alkaline ones, and the highest removal was found at pH 5. Higher reaction temperature can improve the removal of NDMA and reduce the reaction time. Based on the total nitrogen balance, most nitrogen of NDMA was converted to ammonium and dimethylamine.