This field study investigated the phytoremediation potential of two arsenic (As) hyperaccumulating fern species, Pityrogramma calomelanos var. austroamericana and Pteris vittata over 27-month duration at a disused As-contaminated cattle-dip site located at Wollongbar, NSW, Australia. Ferns planted in January 2009 were harvested following 10, 22 and 27 months of growth. A detailed soil sampling was undertaken in June 2009 (initial, n = 42 per plot) and limited sampling in April 2011 (after 27 months, n = 15 per plot) to measure total and phosphate-extractable As concentrations in soil at 0 − 20-, 20 − 40- and 40 − 60-cm depths. The choice of the limited number of samples was considered sufficient to estimate the changes in soil As concentration following phytoremediation based on a geostatistical model. The average frond dry biomass, As concentration and As uptake were significantly (P < 0.001 − 0.05) greater in P. calomelanos var. austroamericana than P. vittata, at all three harvests (1.6 − 4.3, 1.3 − 1.5 and 2.2 − 5.7 times, respectively). After 27-months of growth, P. calomelanos var. austroamericana removed 8,053 mg As (i.e. cumulative over three harvests) in plot B (25.4 kg As ha−1) that was 2.65 times higher than that depleted by P. vittata (3,042 mg As in plot A (9.7 kg As ha−1)). The cumulative frond As uptake data of the two fern species revealed that P. calomelanos var. austroamericana extracted 1.7 − 3.9 % and P. vittata removed 0.53 − 1.5 % of total As from soil at three depths. However, for the surface (0 − 20 cm) and subsurface (40 − 60 cm) layers, the (post-experiment) soil As data indicated that total As concentration in soil was reduced by 49 and 63 % (P < 0.05), respectively, using P. calomelanos var. austroamericana; and 17 and 15 % (P > 0.05), respectively, by P. vittata. Our results show that phytoremediation time based on observed changes in soil As based on limited sampling is not reliable; hence, it is recommended that the frond As uptake should be considered in order to evaluate the phytoremediation efficiency of the two fern species at the experimental site. Using As uptake of the two fern species, we estimate that with P. calomelanos var. austroamericana it would take 55 − 125 years to decrease mean total As content below the ecological investigation level (20 mg kg−1) in the surface and subsurface soils, whereas with P. vittata 143 − 412 years would be required to achieve this target.

GOAL, SCOPE, AND BACKGROUND: Many studies have focused on measuring fine and course particulate matter (PM) in urban and rural sites around the world. The aim of this research is to gain information on the size distribution of particles. The physical characteristics of PM in the urban air of Istanbul were determined. METHODS: PM sampling was carried out at five stations (Avcılar, Beşiktaş, Kilyos, Rasathane, and Göztepe) over a period of 2 years. PM filter samples were collected for eight different size ranges (<0.43, 0.43–1, 1–1.7, 1.7–2.6, 2.6–3.5, 3.5–5.2, 5.2–6.5, 6.5–8, and >8 μm) using a Cascade Impactor. The size distributions of the PM samples were determined. RESULTS AND DISCUSSION: The mean total PM concentrations were 48.6 ± 34.0, 34.8 ± 11.6, 28.6 ± 13.6, 21.5 ± 9.1, and 16.8 ± 5.1 μg/m3 for the Göztepe, Beşiktaş, Avcılar, Rasathane, and Kilyos stations, respectively. The total PM concentrations were found to be 1.2–1.5 times higher in the fall and winter than in the spring and summer, except for at the station in Avcılar. The PM concentrations in Avcılar did not exhibit seasonal variations. This is thought to result from the intense industrial activity in the area. PM2.6 (below 2.6 μm particles) comprised up to 62% of the total amount of PM in samples collected at the Göztepe, Beşiktaş, and Rasathane stations during the fall and winter. PM1 was determined to be approximately 45% of the total, corresponding to 57% of the amount of PM2.5. A multi-modal PM size distribution was observed. The lowest Mass Median Aerodynamic Diameter (MMAD) values observed in Avcılar, Beşiktaş, Rasathane, and Göztepe were 4.2, 3.9, 2.9, and 3.5 μm, respectively, and were observed during the season of active household heating. No difference was measured in the MMAD values (5.2 μm) between the seasons of heating and non-heating in Kilyos.

INTRODUCTION: Flowing of the acid mine drainage may contaminate the adjacent water bodies causing substantial changes in the aquatic ecosystem. This aspect is the most relevant problem in the southern of Santa Catarina once the contaminated areas are inserted in the watershed of the Araranguá, Urussanga, and Tubarão rivers, increasing the need for recovery studies. These areas are between Criciúma, Içara, Urussanga, Siderópolis, Lauro Müller, Orleans, and Alfredo Wagner towns where a conservation unit exist called the Environmental Preservation Area of Baleia Franca. Aiming to compare the kinetics of the ash derived from burning coal and to neutralize acid mine drainage, different neutralizer, limestone, fly, and bottom ash, was mounted on a pilot scale experiment. DISCUSSION: The transport parameters showed the same order of infiltration and dispersion: fly ash < bottom ash < limestone. The order of measured alkalinity was: limestone < fly ash < bottom ash, with pH values of 9.34, 12.07, and 12.25, respectively. The limestone kinetics of acidic drainage neutralization was first order with reaction rate constant k = 0.0963 min−1, bottom ash was 3/4 with k = 0.0723 mol1/4 L−1/4 min−1, and the fly ash had higher order kinetics, 4/3, with reaction rate constant k = 27.122 L1/3 mol−1/3 min−1. However, by mathematical modeling, it was found that due to a combination of transport and kinetics, only limestone treatment reached a pH above 6 within 5 years, corresponding to the ideal as planned.

PURPOSE: The aim of this study is to develop a normalization method for real-time PCR data by analyzing the most stably expressed control genes in mussel (Mytilus edulis) reproductive tissue. METHODS: To facilitate this, six candidate genes, including several commonly used in the literature, were investigated in mussels at different stages of gametogenesis and following experimental exposure to a model estrogen (17b-estradiol). GeNorm and NormFinder softwares were employed to assess the stability of the reference genes. RESULTS: Our results demonstrate that the most stable reference genes are not the same in mussels at different stages of gametogenesis and in experimentally E2-exposed mussels. Interestingly, HEL (helicase) and ACT (actin) mRNA expression levels were most affected by the stage of gametogenesis and yet, in molluscan studies, ACT is possibly the most frequently used reference gene. CONCLUSIONS: We demonstrate that the experimental results are highly dependent on the reference gene chosen and that statistically significant contrasting differences between sample groups are present or absent depending on the reference gene employed.

INTRODUCTION: The photocatalytic degradation of Orange G (OG) dye has been investigated using synthesised nanocrystalline ZnO as a photocatalyst and sunlight as the irradiation source. The formation of ZnO prepared from its precursor was confirmed through FT-IR and powder X-ray diffraction analyses. MATERIALS AND METHODS: Surface morphology was characterised by scanning electron microscope and transmission electron microscope analysis. Band gap energy of synthesised nanocrystalline ZnO was calculated using diffuse reflectance spectroscopy (DRS). Different experimental parameters such as effects of pH, dye concentrations and mass of catalyst were standardised in order to achieve complete degradation of the dye molecules under solar light irradiation. RESULTS: The kinetics of oxidation of OG was also studied. The complete degradation of OG was evident after 90 min of irradiation at an initial pH of 6.86. The degradation of OG was confirmed by UV–Visible spectrophotometer, high-pressure liquid chromatography, ESI-Mass and chemical oxygen demand analyses. CONCLUSION: The adsorption of dye onto catalytic surface was analysed employing model equations such as Langmuir and Freundlich isotherms, and it was found that the Langmuir isotherm model best fitted the adsorption data. The solar photodegradation of OG followed pseudo-first-order kinetics. HPLC and ESI-Mass analyses of the degraded samples suggested that the dye molecules were readily degraded under solar irradiation with nanocrystalline ZnO.

INTRODUCTION: Levoglucosan and carbonaceous species in the background aerosol of coastal southeast China were measured at Jianfengling (JFL), a background mountain site in a National Reserve Park on Hainan Island, and at Hok Tsui (HT), a rural site on the southern coast of Hong Kong from April to May of 2004 during an intensive field study. METHODS: We integrated the information from field study, satellite and backward trajectory model to examine the long-range transport of biomass burning smoke from the Philippines and assess its impact on background aerosol in coastal southeast China. RESULTS AND DISCUSSION: The average levoglucosan concentrations were 42 and 30 ng m−3 at JFL and HT, respectively, while the organic and elemental carbon concentrations were 3.1 and 0.4 μg C m−3 respectively at JFL, and 4.1 and 1.3 μg C m−3 respectively at HT. Elevated levoglucosan concentrations of 85–106 ng m−3 (250–340% extra loadings) at JFL and 57 ng m−3 (170% extra loading) at HT were observed during transport events in which air masses originated from the Philippines. Fire hot spot counts and aerosol index derived from satellite data showed that the spread of biomass burning smoke from the Philippines resulted in large-scale dense aerosol clouds in the adjacent South China Sea and the western Pacific Ocean. The observed high ratio of two biomass-burning tracers (levoglucosan to mannosan) at JFL (7–36) and HT (27) indicated that the biomass smoke originating from the Philippines had significant contributions from open-field burning of agricultural residues, such as rice straw. The pollution plumes were transported to southeast China resulting in elevated concentrations of carbonaceous aerosol and levoglucosan in particular. Using a simplified receptor-based approach, biomass smoke aerosol was estimated to account for 16–28% of OC in the background atmosphere of Hainan and 4.9% of OC at the rural site of Hong Kong during these episode cases, indicating that biomass burning smoke generated in the Philippines could have a significant contribution to background ambient aerosol of southeast coastal China.

PURPOSE: The purpose of this study was to evaluate the influences of volatile organic compounds (VOCs) emissions on hazardousness and photochemical reactivity and to propose efficient VOCs abatement strategies. METHODS: The atmospheric concentrations of 101 components of VOCs were measured at six sites which comprehend four urban areas, a roadside area, and an industrial area in Hyogo Prefecture. VOCs influence on hazardousness and photochemical reactivity were evaluated using VOCs measured data and the index on the health effect evaluation and ozone formation potential. The substances that require emissions reduction were selected from the evaluation results. The state and characteristics of environmental pollution were considered from the concentration trends of the selected substances. RESULTS: In industrial area, n-hexadecane, styrene, vinyl chloride monomer, and 1,2-dichloroethane showed a high concentration. In roadside area, n-hexane, n-undecane, n-dodecane, tetrachloroethylene, formaldehyde, acetaldehyde, and 1-butanol showed a high concentration. The excess cancer incidences for formaldehyde exceeded 10−5 of the level of concern for carcinogenic effect at all sites. Toluene had a high percentage of ozone production. The interannual and seasonal trends of toluene concentrations were different at a regional level and the formaldehyde concentrations in summer were significantly higher than those in winter at the urban sites. CONCLUSIONS: The results show the need to prepare the emission reduction plan for the major sources such as vehicle exhaust, solvent use, and industrial processes to diminish the concentration of toluene that contributes significantly to the formation of photochemical oxidant.

PURPOSE: With the aim of enhanced degradation of azo dye alizarin yellow R (AY) and further removal of the low-strength recalcitrant matter (LsRM) of the secondary effluent as much as possible, our research focused on the combination of aerobic bio-contact oxidation (ABO) with iron/carbon microelectrolysis (ICME) process. MATERIALS AND METHODS: The combined ABO (with effective volume of 2.4 l) and ICME (with effectively volume of 0.4 l) process were studied with relatively short hydraulic retention time (HRT) of 4 or 6 h. RESULTS: At the HRT of 6 h with the reflux ratio of 1 and 2, the AY degradation efficiency in the final effluent was >96.5%, and the total organic carbon (TOC) removal efficiency were 69.86% and 79.44%, respectively. At the HRT of 4 h and the reflux ratio of 2, TOC removal efficiency and AY degradation efficiency were 73.94% and 94.89%, respectively. The ICME process obviously enhanced the total AY removal and the generated micromolecule acids and aldehydes then that wastewater backflow to the ABO where they were further biodegraded. CONCLUSION: The present research might provide the potential options for the advanced treatment azo dyes wastewater with short HRT and acceptable running costs.

INTRODUCTION: The pollution of soil and environment as a result of human activity is a major problem. Nowadays, the determination of local contaminations is of interest for environmental remediation. These hotspots can have various toxic effects on plants, animals, humans, and the whole ecological system. However, economical and juridical consequences are also possible, e.g., high costs for remediation measures. MATERIALS AND METHODS: In this study three sampling strategies (simple random sampling, stratified sampling, and systematic sampling) were applied on randomly distributed hotspot contaminations to prove their efficiency in term of finding hotspots. The results were used for the validation of a computerized simulation. RESULTS AND CONCLUSION: This application can simulate the contamination on a field, the sampling pattern, and a virtual sampling. A constant hit rate showed that none of the sampling patterns could reach better results than others. Furthermore, the uncertainty associated with the results is described by confidence intervals. It is to be considered that the uncertainty during sampling is enormous and will decrease slightly, even the number of samples applied was increased to an unreasonable amount. It is hardly possible to identify the exact number of randomly distributed hotspot contaminations by statistical sampling. But a range of possible results could be calculated. Depending on various parameters such as shape and size of the area, number of hotspots, and sample quantity, optimal sampling strategies could be derived. Furthermore, an estimation of bias arising from sampling methodology is possible. The developed computerized simulation is an innovative tool for optimizing sampling strategies in terrestrial compartments for hotspot distributions.

This short review presents the procedures used to monitor PAHs, phthalates and psychotropic substances in the air, and the results of some measurements made in Italy and abroad. Organic contaminants are characterized by a variety of physical and chemical properties, including aggregation phase, concentration level, and life time. This variety widens the spectrum of procedures developed to assess their occurrence in the environment and biota, but prevents the complete speciation of the “organic fraction” of air, waters and particulates, and attention is paid to a few substances. The progress in health sciences stimulates the concern on contaminants and the development of new instrumental apparatuses and methods; new chemicals are continuously identified or recognized as capable of injuring the environment and organisms. Persistent organic pollutants and persistent biologically active toxicants are subject to regulation and extensively measured by means of standard procedures. For instance, polycyclic aromatic hydrocarbons, polychlorobiphenyls and polychlorodibenzodioxins are recovered from air through phase partition, thermal desorption or solvent extraction, then separated and detected through GC–MS or HPLC–MS procedures. By contrast, dedicated methods must be still optimized to monitor candidates or possible candidates as emerging organic pollutants, e.g. phthalates, flame retardants and perfluoroalkanes. Also, psychotropic substances appear of potential concern. Legal and illicit substances are commonly detected in the urban air besides waste and surface waters. If nicotine, caffeine and cocaine will result to enough persistence in the air, their monitoring will become an important issue of global chemical watching in the next future.