Sculpins are widely used as key species for monitoring heavy metal pollution near arctic mine sites. Typically, metal concentrations in liver and muscle tissue have been used as a proxy for metal exposure but such analyses lack temporal information of uptake and accumulation. Otoliths (ear bones) are considered metabolically stable and can potentially contain a complete record of the fish’s metal exposure history. To investigate the otolith chemistry of sculpins and the potential of these as records of metal exposure, common sculpins (Myoxocephalus scorpius) were collected at five sites near a former Pb–Zn mine in West Greenland. Otoliths were analyzed by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for 12 elements of which Mg, Mn, Sr, Ba, and Pb were detected. The highest Pb concentrations were found within the otoliths from the most Pb-polluted sites near the mine (up to 0.6 ppm), and decreasing concentrations were observed in a gradient away from the mine. Notably, Pb and Sr variations were closely correlated and showed an annual oscillatory pattern with peaks consistently found in the winter zones. It is not clear to what the extent high winter-time accumulation of Pb in the otoliths is due to high winter-time exposure of Pb through diet or water and/or to physiological processes such as growth in the sculpins. The study indicates that LA-ICP-MS analyses of sculpin otoliths have the potential to become a valuable method for assessing time-resolved metal loading near mine sites but also that more studies are required to investigate the links between metal sources, pathways, and processes affecting otolith metal deposition.

Biosorption is a low-cost green technology for water pollution decontamination. Recently, new adsorbent materials (raw or modified) were synthesized and tested in a wide variety of different pollutants. Among them, researchers pay attention on an alternative use of composts. The major use of composts is as soil amendments to improve the fertility of soils. For the first time in literature, the present review article gathers information about the applicability of compost materials as biosorbents in batch modes. For this purpose, equilibrium modeling and isotherm, kinetic, and thermodynamic studies were discussed in details. Moreover, many parameters such as temperature, pH, and contact time were also analyzed. The main pollutants studied in this work are dyes and heavy metals either in single- or multi-component systems.

This study investigates the use of sericite beads and microalgae for the removal of heavy metals from acid mine drainage (AMD) and the simultaneous enhancement of biomass productivity. The experiment was conducted over a period of 6 days in a hybrid system containing sericite beads and microalgae Chlorella sp. The results show that the biomass production increased to ~8.04 times its initial concentration of 0.367 g/L as measured by an optical panel photobioreactor (OPPBR) and had a light transmittance of 95 % at a 305-mm depth. Simultaneous percent removal of Fe, Cu, Zn, Mn, As, and Cd from the AMD effluent was found to be 97.78 to 99.26 %. Biomass production was significantly enhanced by removal of heavy metal ions. We thus found that our hybrid system of sericite beads and microalgae was highly effective in removing heavy metal and in enhancing biomass production and could be a useful alternative treatment of AMD.

The impacts of phenanthrene and its nitrogen-containing analogues (N-PAHs) on seedling emergence and plant biomass of two terrestrial plant species, Lactuca sativa (lettuce) and Lolium perenne (rye grass), were investigated in soil over a 21-day exposure period. The data over 0–90-day soil-chemical contact time revealed that seedling emergence and plant biomass were significantly affected by N-PAHs even at the lowest concentration of 10 mg/kg. N-PAH amended soils showed greater inhibitory effects on seedling emergence and early plant biomass than phenanthrene amendments with incubations overtime. The degree of inhibition (% inhibition) on seedling emergence over time was 33.3 % (lettuce) and 46.7 % (rye grass) for the phenanthrene, and 53.3 % (lettuce) and 93.3 % (rye grass) for the N-PAHs, respectively, suggesting greater sensitivity of seedling emergence and early plant biomass on N-PAH-contaminated soil. The results from this study will contribute to data gaps for poorly managed chemicals/chemical groups for environmental risk assessment and might be useful in the development of new approaches for hazard assessment of contaminated systems.

Thermal stability is one of the most important indexes determining the practical applications of selective catalytic reduction (SCR) catalysts. The influence of typical alkali element on the thermal stability of industrial V₂O₅-WO₃/TiO₂ catalyst is first reported in this work. The activity of the sample is measured, and physicochemical properties are characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectrum, field emission scanning electron microscope (FE-SEM), N₂ adsorption-desorption, temperature programmed desorption of NH₃ (NH₃-TPD), and in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS). The sintering and anatase-to-rutile phase transformation at high temperature will cause deactivation of SCR catalyst, and low concentration of K can increase the thermal stability. Under the same thermal treatment, the activity (380 °C) of sample deposited by K is more than three times higher than that of the fresh sample without K. Aggregation of vanadia in conventional SCR catalyst favors the sintering and anatase-to-rutile phase transformation of catalysts. Incorporation of K can modify the structure of partial V-OH and form V-OK, which hinders the aggregation of vanadia species and further increases the thermal stability of catalysts.

Nitrogen inputs to coastal watersheds have been linked to eutrophication. However, the role that domestic sources of wastewater play in contributing nitrogen to coastal watersheds is not well known in the southeastern USA. In a yearlong study (2011–2012), nitrogen concentrations were compared in watersheds served by septic systems and a centralized sewer system in the Coastal Plain of North Carolina. Surface and groundwater samples from septic systems and sewer watersheds were analyzed for total dissolved nitrogen (TDN), total nitrogen, and nitrogen and oxygen isotopes in nitrate. Groundwater beneath the drainfield and adjacent to streams had median concentrations of TDN at 5.9 and 4.4 mg/L, respectively. Additionally, median groundwater-transported loads of TDN to the stream from septic systems sites (0.6 kg-TDN/year) were significantly greater than sites in sewer watersheds (0.2 kg-TDN/year). Isotopic analyses revealed that effluent from septic systems was the primary source of nitrate in watersheds served by septic systems, while fertilizer and/or soil organic matter were dominant sources of nitrate in sewer watersheds. Nitrogen exported from septic systems contributed to elevated nitrogen concentrations in groundwater and streams throughout the watershed, whereas nitrogen exports from sewers were focused at a single point source and affected surface water concentrations. Based on watershed TDN exports from septic systems minus TDN exports from sewers watersheds, it was estimated that septic systems contributed 1.6 kg TDN/ha/year to watershed exports of TDN. Overall, septic systems and sewers contributed to elevated nitrogen loading and should be considered in nutrient-sensitive watershed management.

The study analyzes the presence and the origin of heavy metals in environmental compartments affected by anthropogenic activities. The paper presents the results of a field study performed on the sediments of two of the main small urban creeks of the city of Prague (Czech Republic). The aim of the survey was to verify the presence and bioavailability of heavy metals (Cu, Cr, Ni, Pb, Zn) in the aquatic environment (water as well as bottom sediments), and to assess the source of these pollutants. The results were processed to evaluate the enrichment factor and the partition coefficient, and were statistically analyzed through the analysis of variance and the principal component analysis. Comparison with relevant environmental quality standards showed that measured heavy metal concentrations were always lower than the probable effect concentration (PEC). On the contrary, the threshold effect concentration (TEC) was frequently exceeded. Sequential extraction analysis showed that the bioavailability of studied metals is quite high, suggesting that they could be easily released from the sediment to the aquatic environment. Overall, several sources of pollution, different for the different metals, were identified, all related with anthropogenic factors.

In the present study, facile and competent homogeneous liquid–liquid microextraction via flotation assistance (HLLME-FA) method combined with flow injection flame atomic absorption spectrometry (FI-FAAS) was proposed for simultaneous separation/preconcentration and determination of trace amounts of cadmium and copper in water samples. The efficient 2-(3,4-dihydroxyphenyl)-1,3-dithiolane (DHPDTO) with thiol groups was used as chelating reagent. The predominant parameters influencing the HLLME-FA, such as solution pH, concentration of DHPDTO, extraction and homogeneous solvent types and volumes, ionic strength, and extraction time were studied. Applying all the optimum conditions in the process, the detection limits of 0.008 and 0.01 μg L⁻¹, linear ranges of 0.08–40 and 0.1–45 μg L⁻¹, and the precision (RSD%, n = 7) of 3.4 and 3.9 % were obtained, respectively, for cadmium and copper. The proposed procedure showed satisfactory results for analysis of tap water, river water, well water, and seawater.

Exposure to benzene has been associated with multiple severe impacts on health. This notwithstanding, at most monitoring stations, benzene is not monitored on a regular basis. Data were used from two different monitoring stations located on the eastern Mediterranean coast: (1) a traffic monitoring station in Tel Aviv located in an urban region with heavy traffic and (2) a general air quality monitoring station in Haifa Bay located in Israel’s main industrial region. At each station, hourly, daily, monthly, seasonal, and annual data of benzene, NO ₓ , mean temperature, relative humidity, inversion level, and temperature gradient were analyzed over 3 years: 2008, 2009, and 2010. A prediction model for benzene rates based on NO ₓ levels (which are monitored regularly) was developed to contribute to a better estimation of benzene. The severity of benzene pollution was found to be considerably higher at the traffic monitoring station than at the general air quality station, despite the location of the latter in an industrial area. Hourly, daily, monthly, seasonal, and annual patterns have been shown to coincide with anthropogenic activities (traffic), the day of the week, and atmospheric conditions. A strong correlation between NO ₓ and benzene allowed the development of a prediction model for benzene rates based on NO ₓ , the day of the week, and the month. The model succeeded in predicting the benzene values throughout the year. The prediction model suggested in this study might be useful for identifying potential risk of benzene in other urban environments.

The majority of the existing water bodies around the world are increasingly polluted with oily wastewater. The aim of this study was to investigate the role of single protozoan isolates (Aspidisca, Trachelophyllum and Peranema) and of a consortium of these three protozoan isolates in the biodegradation of fats and oils present in polluted domestic wastewater. The biomass of protozoan isolates, chemical oxygen demand (COD), dissolved oxygen (DO) and concentrations of fats and oils were determined in triplicate before and after the inoculation of isolates in oily wastewaters, using standard methods. Results revealed optimum growth of protozoan cell densities under favourable conditions of 30 °C, pH 6 and 8 (from 1.00 to 4.00, 3.96, 3.80 and 4.20 × 10²cells/ml for Aspidisca, Trachelophyllum, Peranema and a consortium of the three isolates, respectively). The average percentage uptake of DO by Aspidisca, Trachelophyllum, Peranema and their consortium was 95, 96, 96 and 100 %, respectively, for both 30 and 25 °C and at pH levels of (4, 6, 8 and 10), respectively. The results revealed that the COD removal rates of the isolates at various pH levels were ≥20 and ≤90 %, respectively, for 30 and 25 °C. At a temperature of 30 °C, the biodegradation capabilities of the isolates ranged from 3.0 to 8.0, 3.0 to 6.0, 7.0 to 11.0 and 8.0 to 22.0 %, while at 25 °C, the biodegradation rates were 3.0 to 6.0, 4.0 to 7.0, 3.0 to 8.0 and 4.0 to 15.0 % for Aspidisca, Trachelophyllum, Peranema and the consortium of these three isolates, respectively.