Although concentrations of endocrine-disrupting chemicals (EDCs) in seawaters of Japan are relatively low, vitellogenin and ovotestis inductions are still being observed in some males of mullet and flounder collected in coastal areas. These fish species are benthic and could be affected by EDCs in marine sediments. Therefore, the concentrations of EDCs in marine sediments of Osaka Bay were determined by LC-MS/MS. In addition, the estrogen receptor binding potencies as estrogenic potencies of these sediments were assessed by the medaka estrogen receptor-α binding assay. Results show that estrogenic potencies were higher in sediments of the inner part of the bay especially at station 13 (off Sakai City) where quite strong estrogenic potency was detected. Through calculation of total E2 equivalent concentration (EEQ) in sediments, it was established that approximately 50 % of estrogenic potency was due to nonylphenol (NP), estrone and 17β-estradiol, suggesting that these compounds play important roles as endocrine disruptors in coastal environments of Osaka Bay.

The current study estimates premature mortality caused by long-term exposure to elevated concentrations of PM₂.₅ (particulate matter with aerodynamic diameter equal to or less than 2.5 μm) in Japan from 2006 to 2009. The premature mortality is calculated based on a relative risk of 1.04 (95 % CI, 1.01–1.08) per 10 μg m⁻³ increase above the annual mean limit of 10 μg m⁻³ taken from the World Health Organization Air Quality Guidelines. The spatiotemporal variations of PM₂.₅ are estimated based on the measurements of suspended particulate matter (SPM) (with aerodynamic diameter approximately less than 7.0 μm) at 1,843 monitors. The improvements of air quality in Japan by reducing the emissions of SPM from 2006 to 2009 could save 3,602 lives based on a reduction target of 10 μg m⁻³ annual mean concentration. This finding could be a tangible benefit gained by reducing the emissions of particulate matter in Japan.

Application of an agricultural residue (rice husk, RH) as a raw material for catalyst support for advanced oxidative processes (AOPs) was evaluated. The supported catalyst was produced by the calcination of TiCl₄ impregnated in RH, thereby providing a composite TiO₂/Si-C, which was characterized by elemental analysis (CHN), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM–EDX), X-ray photoelectron spectroscopy (XPS), UV/VIS diffuse reflectance spectroscopic (DRS), diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), atomic force microscopy (AFM), SEM, and nitrogen adsorption–desorption isotherms (BET and BJH). Catalytic photodecomposition of methylene blue (MB), naphthalene, phenol, and abamectin and acid drainage of a mine by a titania-based catalyst composite were investigated. For comparative purposes, a commercial photocatalyst (TiO₂) was also employed. Photocatalytic degradation of MB, phenol, naphthalene, abamectin, and from coal mining effluent ranged from 8 to 93 % of the initial concentration. Performances of both catalysts were comparable. Additionally, in these evaluated systems, the toxicity of the effluent decreased after photocatalysis, either for Daphnia magna or for Scenedesmus subspicatus (employed as bioindicators).

The speciation of mercury (Hg) is a major determinant of its methylation rate by sulfate-reducing bacteria (SRB), considered the primary methylators. Under anoxic conditions, sulfur (S) cycling may have a significant influence on Hg complexation and methylation, by influencing both SRB activity and the pool of available reduced S ligands, as the presence of zero-valent sulfur (S(0)) in sulfidic water results in the formation of polysulfides. While SRB frequently coexist with S-oxidizing bacteria in natural environments, the effect that these organisms may have on methylation by SRB is not understood. In this study, we investigate the role of S(0) in methylation by SRB monocultures and cocultures with phototrophic green or purple S-oxidizing bacteria. In the coculture experiments, the presence of S-oxidizers was found to increase Hg methylation rates, apparently by maintaining favorable chemical speciation in the environment. The measured Hg methylation rates were in accord with predictions based on geochemical modeling of speciation. In SRB monoculture experiments conducted in the presence and absence of S(0), the data showed that at limited total Hg, the presence of polysulfides resulted in decreased Hg methylation, presumably by causing a decrease in the most bioavailable Hg–sulfide complexes. These results indicate that models of Hg speciation and methylation in the environment should include a detailed investigation of S redox speciation.

The objectives of this study were to assess susceptibility to acidification and nitrogen (N) saturation caused by atmospheric deposition to northeastern US forests, evaluate the benefits and shortcomings of making critical load assessments using regional data, and assess the relationship between expected risk (exceedance) and forest health. We calculated the critical loads of nutrient N and of sulfur (S) + N using the steady-state mass balance method at >4,000 regional and national vegetation and soil monitoring network plots in the northeastern USA. Regional calculations of critical loads necessitate use of soil maps which provide a range for each soil characteristic resulting in a broad range of critical load of S + N and exceedance values. For the scenario most representative of regional conditions, over 80 % of the critical loads fell into the range of 850–2050 eq ha⁻¹ yr⁻¹; at 45 % of the plots, deposition exceeded the critical load. In contrast, the critical load for nutrient N, 200–300 eq ha⁻¹ yr⁻¹, was lower. Site measurements, especially to estimate soil weathering, would increase the certainty of the critical load. We observed significant negative correlations between critical load exceedance and growth (17 species) and crown density (4 species); we observed significant positive correlations of exceedance with declining vigor (four species), with crown dieback (six species) and crown transparency (seven species). Among the species which demonstrate the most significant detrimental responses to atmospheric deposition are balsam fir, red spruce, quaking aspen, and paper birch. These results indicate that significant detrimental responses to atmospheric deposition are being observed across the northeastern USA.

The present work tested effects of a revegetation pattern conducted using Paulownia fortunei (Seem.) Hemsl. (Scrophulariaceae) on soil chemical properties and actinomycete community structure identified by terminal restriction fragment length polymorphism (T-RFLP) technology of 16S rDNA. The results indicated that P. fortunei planting with time effectively improved organic carbon and total nitrogen contents, as well as pH in heavy metal-contaminated soils and, at the same time, enhanced the retention of heavy metals such as Pb, Zn, Cu and Cd in soils. T-RFLP profiles of soil actinomycete communities digested from two restriction enzymes (HhaI and RsaI) showed different specific TRF patterns across four sites with different revegetation time. Nonetheless, number and diversity of terminal restriction fragments for soil actinomycete community increased gradually with P. fortunei planting time and followed consistent patterns with soil organic carbon, total nitrogen, pH and heavy metal contents. Our results revealed a great potential of P. fortunei to remediate heavy metal-contaminated soils.

Humic acids (HA) are known as the precursors of carcinogenic compounds formed by the disinfection of drinking water. While conventional treatments were found to be inefficient HA removal processes in drinking water, advanced oxidation processes have been proven to have a significant effect in the treatment of HA. The degradation of HA was investigated using nano-sized zinc oxide (ZnO)/laponite composite (NZLC). The reactions occurred in a UVC reactor by considering following variables: pH, initial HA concentration, catalyst loading, addition of hydrogen peroxide (H2O2), and catalyst reuse. Water samples containing HA were analysed by ultraviolet/visible spectrophotometer and high-performance size-exclusion chromatography. Initial HA concentrations were tested by the Langmuir-Hinshelwood model with k and K ads values, determined to be 0.126 mg/L.min and 0.0257 L/mg, respectively. The change in pH affected the HA degradation efficiency by the photocatalytic activity where it was higher under acidic conditions rather than alkaline ones. Optimal catalyst loading was proved to be a constrained factor in influencing the photocatalytic efficiency: the increase of catalyst concentration enhanced the HA decomposition efficiency up to an optimum value of 20 g/L, where there was no further degradation with excess loading. The addition of H2O2 was investigated through homogenous and heterogeneous photocatalysis, and, heterogeneous photocatalysis showed higher removal efficiency due to the combined effect of both catalysts and H 2O2. Finally, NZLC was effective for reuse and exhibited an excellent stability after six times of usage. © 2013 Springer Science+Business Media Dordrecht.

Two mine soils in southeastern Ohio do not support a luxurious vegetation growth probably because of soil-related constraints. Thus, a laboratory study was conducted to improve the mine soil quality using amendments of zeolite (two grain sizes), flue gas desulfurization gypsum (FGD), fly ash, and biosolids at an application rate of 10 % by weight. The results showed that FGD was the best amendment for increasing soil pH and improving seed germination of lettuce (Lactuca sativa) while biosolids significantly enhanced soil aggregate stability and saturated-water-holding capacity. Specifically, FGD increased soil pH from 3.1 to 5.0, and 4.2 to above 7.0, respectively. Elongation of the lettuce seedlings (shoots) in mine soil solutions was also enhanced by the amendment, from an initial length of 0-1.5 cm to 4.5-9.6 cm. Application of biosolids, on the other hand, increased the mean weight diameter of soil water-stable aggregates by two to four times from initial 0.5-1.6 mm to 2.0-2.9 mm. Saturated-water-holding capacity of both soils was also significantly improved by biosolids. But biosolids did not enhance soil plant-available-water-holding capacity. Neither zeolite nor fly ash significantly improved the mine soil qualities measured in our study. Soil chemical analyses showed that these mine soils neither contained high concentrations of heavy metals nor other toxins in solids or in solutions, suggesting that soil acidity is the only chemical constraint limiting the vegetation establishment and growth besides the nutrients deficiency. © 2013 Springer Science+Business Media Dordrecht.

Finding an environmentally safe and cost-effective method which is efficient enough to meet the regulatory standards of potable and industrial wastewater presents unique challenges. In this work, Moringa stenopetala seed powder which had particle size of 300 μm was characterized; ash content 4.7 %, bulk density 0.531/cm3, particle density 0.88 g/cm3, color yellowish, and pH 4.5. Fourier transform infrared spectroscopy analysis showed the multifunctionality of the M. stenopetala seed powder. M. stenopetala seed powder was assessed for percentage chromium removal and milligrams per gram chromium uptake as a function of contact time, pH, and dose of the adsorbent and initial concentration. The maximum percent removal was 99.74 %. Sorption kinetics of chromium adsorption by M. stenopetala seed powder was predicted reliably using a pseudo-second order model. An intra-particle diffusion model revealed that the biosorption of metals proceeds through various processes. Equilibrium uptakes were evaluated using Langmuir, Freundlich, Temkin, and the Dubinin-Radushkevich adsorption isotherm models. Even though the correlation coefficient was not as high as the Langmuir and Freundlich models for Temkin adsorption isotherm model, the metal uptake which was predicted by the model is comparable with the experimental value. Generally, the seed powder of M. stenopetala was found to be effective in the removal of chromium from tannery wastewater. © 2013 Springer Science+Business Media Dordrecht.

The aims of the present study were to identify the halophilic Archaea that can degrade aromatic hydrocarbons (namely, p-hydroxybenzoic acid, naphthalene, phenanthrene, and pyrene) and to determine their catabolic pathways in the process of degrading the hydrocarbons. It was determined nine archaeal isolates used p-hydroxybenzoic acid, naphthalene, phenanthrene, and pyrene as sole carbon and energy sources. The isolates were identified as Halobacterium piscisalsi, Halorubrum ezzemoulense, Halobacterium salinarium, Haloarcula hispanica, Haloferax sp., Halorubrum sp., and Haloarcula sp. by 16S rRNA gene sequences. Activity of catechol 1,2 dioxygenase and protocatechuate 3,4 dioxygenase enzyme of the ortho cleavage pathway were detected. Determination of the genes of these dioxygenases was also shown. This study clearly demonstrated for the first time that Halorubrum sp. and H. ezzemoulense among the isolates were able to grow at 20 % (w/v) NaCl, utilizing p-hydroxy-benzoic acid, naphthalene, phenanthrene, and pyrene as the sole carbon sources.