Zamioculcas zamiifolia has the potential to reduce the concentration of benzene, toluene, ethylbenzene, and xylene (BTEX) from contaminated indoor air. It can remove all four pollutant gases. Benzene, toluene, ethylbenzene, and xylene uptake per unit area of Z. zamiifolia leaf were about 0.96 ± 0.01, 0.93 ± 0.02, 0.92 ± 0.02, and 0.86 ± 0.07 mmol m -2 at 72 h of exposure, respectively. The physicochemical properties of each BTEX may affect its removal. Benzene, a smaller molecule, is taken up by plants faster than toluene, ethylbenzene, and xylene. The toxicity of BTEX on plant leaves and roots was not found. The chlorophyll fluorescence measurement (F v/F m) showed no significantly difference between controlled and treated plants, indicating that a concentration of 20 ppm of each gas is not high enough to affect the photosynthesis of the plants. The ratio of stomata and cuticles showed that 80 % of benzene, 76 % of toluene, 75 % of ethylbenzene, and 73 % of xylene were removed by stomata pathways, while 20, 23, 25, and 26 % of them were removed by cuticles. The BTEX removal efficiency by well-watered Z. zamiifolia was involved with day stomata opening and night closing, while the BTEX removal efficiency by water-stressed Z. zamiifolia can occur both day and night at a slightly lower rate than well-watered plants. © 2013 Springer Science+Business Media Dordrecht.

Accumulation of metals in aquatic organisms is influenced by several factors, including the presence of other metals; therefore, there is a need to study the effects of mixtures of other metals on the accumulation of a particular metal on the organisms. In this study, the capacity for nickel (Ni) regulation by the juvenile decapod crustacean Penaeus vannamei was analyzed. The effects of both solely Ni exposure and in the presence of other metals such as zinc (Zn), lead (Pb), and cadmium (Cd) in a mixture were analyzed to determine any possible synergism. A previous study revealed that a metal mixture of Zn, Cd, and Pb without Ni induces a higher metal uptake in P. vannamei for all three metals, but in this study, no effect was observed for Ni. The results showed no change in the regulatory capacitance for Ni, even in the presence of other metals. The observed capacity of P. vannamei to regulate body concentrations of nickel prevents its use as a suitable biomonitor for this metal.

Direct ultrafiltration and its combination with pretreatment by coagulation/flocculation/sedimentation using Moringa oleifera as coagulant to treat dairy industry wastewater were investigated. A single-channel tubular ceramic membrane with an average porosity of 0.1 μm was used at transmembrane pressures of 1, 2, and 3 bars, using the cross-flow filtration principle in a membrane filtration unit. Process efficiency was evaluated in terms of chemical oxygen demand (COD), apparent color, and turbidity removal, along with major requirements such as average permeate flux, percentage of fouling, and contribution of different resistances (resistances in series model) to the total resistance of the membrane. The highest removals for the evaluated parameters occurred in the combined coagulation/flocculation/sedimentation/ultrafiltration process. At a pressure of 2 bar, the removal of turbidity and apparent color was 99.9 % and that of COD was 98.5 %. For the combined process, the lowest percentage of fouling was 59.8 %, which occurred at 1 bar. The fraction of resistance due to fouling, which may indicate irreversible damage of the membrane, was lower in the process of coagulation/flocculation/sedimentation using M. oleifera as coagulant followed by ultrafiltration than in the process that treated dairy wastewater with direct ultrafiltration for all pressures. © 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.

Soil contamination by crude oil is a major environmental and health hazard. Extraction of the total petroleum hydrocarbons (TPH) sorbed to the clay soil (kaolin) was carried out using synthetic sorbent (Desmopan®) and 2-propanol as a mobilizing agent. The crude oil-loaded polymer beads were bioregenerated in a solid–liquid two-phase partitioning bioreactor (TPPB). A central composite design under response surface methodology was employed for the experimental design and analysis of the results. The independent variables were extraction phase to soil ratio, mobilizing agent to soil ratio, and initial concentration of crude oil in polluted soil. The influences of three independent variables on the TPH reduction efficiency were determined using a statistically significant quadratic model (R ² = 0.9673). Remediation was more efficient when the mobilizing agent to the soil ratio was equal to 3.00 ml g⁻¹, compared to the higher (4.00 ml g⁻¹) and lower (2.00 ml g⁻¹) levels. The results exhibited that the interaction between the extraction phase ratio and the initial concentration of crude oil in kaolin had significantly influenced the TPH removal. The bioregeneration studies showed a significant reduction (72.07 ± 0.63 %) of low-molecular-weight (two- to three-ring) polycyclic aromatic hydrocarbons and n-alkanes (97.75 ± 0.26 %) present in the crude oil-loaded solid polymers within a 10-day experiment. These findings show that solid polymer extraction followed by bioregeneration of sorbents in a TPPB is applicable to treat crude oil-contaminated kaolin.

Lanthanum/aluminum-modified zeolite adsorbent (La/Al-ZA) was prepared and investigated for their ability to remove phosphorus from wastewater. Various batch adsorption conditions, e.g., pH, ionic strength, temperature, contact time, initial phosphorus concentration, and the dosage of adsorbent were tested. The results showed that the adsorption amount increased with the increase of temperature, contact time, and initial phosphorus concentration and decreased with the increase of adsorbent dosage and initial anion concentration. The adsorption amount first increased with increasing pH from 2.0 to 4.0 and reached a plateau over the pH range from 4.0 to 8.0, then significantly decreased from 8.0 to 12.0, and the suitable adsorption was achieved with the pH range 4–9. The phosphorus removal efficiency decreased slightly from 95.86 to 93.39 and 92.53 %, respectively, in the presence of Cl⁻ and SO₄²⁻ at the lower concentration of 0.1 mmol/L, while they decreased significantly from 95.86 % to the ranges of 85.02–88.80 % and 83.77–87.45 %, respectively, in the presence of Cl⁻ and SO₄²⁻ at higher concentrations ranging from 0.5 to 2.0 mmol/L, and the effects on adsorption of La/Al-ZA follow the order: Cl⁻ > SO₄²⁻. Phosphorus adsorption matched with both Langmuir and Freundlich isotherms. The results presented here supported the potential use of the new La/Al-ZA as a material for the treatment of phosphorus in wastewater.

Rapid expansion of natural gas drilling in Sublette County, WY (1999-present), has raised concerns about the potential ecological effects of enhanced atmospheric nitrogen (N) deposition to the Wind River Range (WRR) including the Class I Bridger Wilderness. We sampled annual throughfall (TF) N deposition and lichen thalli N concentrations under forest canopies in four different drainages of the WRR. Measurements of TF N deposition and N concentrations in lichen thalli were highest at plots closest to drilling operations (<30 km). N concentrations in lichens decreased exponentially with distance from drilling activity. Highest TF N deposition, 4.1 kg ha -1 year-1, coincided with clear evidence of damage to lichen thalli. This deposition value is above estimated preindustrial deposition conditions (0.9 kg N ha-1 year-1) and regional critical loads (a deposition value below which ecosystem harm is prevented) of N deposition for sensitive ecosystem components. N concentrations in Usnea lapponica were strongly correlated (r = 0.96) with TF N deposition, demonstrating that elemental analysis of lichen material can be used to estimate TF N deposition. N concentrations below 1.35 % in U. lapponica and 1.12 % in Letharia vulpina were associated with estimated background conditions of 0.9 kg N ha-1 year-1. Additional lichen sampling in the Bridger Wilderness is recommended to further quantify and monitor spatial patterns of N deposition and to define areas of elevated N deposition. © 2013 Springer Science+Business Media Dordrecht (outside the USA).

We studied the effects of N deposition (0, 10, 20 and 50 kg N ha⁻¹ year⁻¹) on cover and physiology of Pleurochaete squarrosa, a terricolous moss from semiarid Mediterranean ecosystems. We also investigated the effects of N fertilization under competition with vascular plants or under water stress. Under greenhouse conditions, vascular plant competition reduced moss cover, and there was a significant interaction between N and competition. Water stress reduced moss cover under high and low competition conditions. Nitrogen fertilization increased moss cover irrespectively of the N dose supplied at low competition conditions. Under field conditions, N deposition affected moss physiology but not cover. Most of the physiological variables analyzed responded to N deposition, although the response of some of them was saturated with only 10 kg N ha⁻¹ year⁻¹ over the background (nitrate reductase; phosphomonoesterase; tissue N and K⁺). The response of indicators such as chlorophyll a and lutein contents did not show any evidence of saturation, which probably makes them the best candidates in monitoring programs. Based on the data provided, the applicability of the phosphomonoesterase can also be considered. In addition, the importance of taking into account the existence of superimposed environmental gradients (such as those in soil mineral N content) interacting with the response of P. squarrosa to predict impacts of N deposition has been demonstrated. Therefore, detailed soil surveys and integrative physiological evaluations will be required to produce a significantly better picture of the effects of N deposition on Mediterranean ecosystems along extant N deposition gradients.

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.

A titanium mesostructure was synthesized, and its surface was subsequently modified by adsorbing phosphate. The modified structure was later investigated for photocatalytic activity against the organic contaminant 2,4,6-trichlorophenol with UV irradiation. This research found that the effects of calcination temperature, phosphate concentration for surface modification, amine grafting as a function, and initial pH condition contributed to the enhanced degradation rate of the chlorinated phenol. The results of this study demonstrated an increased photocatalytic degradation rate for 2,4,6-trichlorophenol under the following conditions: (1) titanium mesostructure calcined at 600 °C; (2) adsorption from a 100 mg/L as PO₄-P solution; (3) an amine-functionalized titanium mesostructure synthesized with the molar ration of 1:0.5 (titanium mesostructure: amine group); and (4) acidic condition (pH 4) to promote efficient adsorption of phosphate. This research indicates that phosphate removal and enhanced degradation of organic contaminants could be carried out simultaneously in sewage treatment.