The recent rapid expansion of nanotechnologies has increased concern over the impact of engineered nanoparticles (ENPs) on the environment and biota. Although the toxicity of ENPs has received considerable attention in the recent years, there are still gaps in our knowledge of the mechanisms responsible for their effects. In this study, we tested the toxicity of various metal oxide ENPs (Al₂O₃, CuO, Fe₃O₄, MnO, TiO₂, and ZnO), including nanowires together with their bulk counter particles and soluble metal salts, on germinating seeds of Sinapis alba L. Fe₃O₄, TiO₂, MnO₂, and Al₂O₃ ENPs did not negatively affected seed germination at any tested concentrations. However, CuO and ZnO ENPs showed a dose-dependent inhibition of germination. Metal ions were more toxic than metal oxide particles at corresponding concentrations. The highest toxicity was exhibited by Cu, followed by Zn, Fe, Al, and Mn ions. A comparison of ENPs with bulk materials did not reveal significantly higher ENP toxicity. Similarly, nanowires showed effects similar to other nanoparticles and bulk materials. Our results indicate that the nanosize or shape of particles did not play a crucial role, whereas metal ions released into cultivation media and accumulated in seedlings contributed significantly to the phytotoxicity of metal oxides.

This study proposes a factorial inexact stochastic fuzzy chance constraint programming framework for dealing with uncertainties in municipal solid waste management under consideration of greenhouse gas (GHG) emission trading. It can reflect uncertainties expressed as fuzzy, interval, and random variables and generate desired management strategies for minimizing the integrated cost for solid waste disposal and purchasing GHG emission credit. Moreover, multilevel factorial analysis is conducted to reveal the main and interactive effects of uncertain parameters. The results show that effective waste allocation schemes can be obtained to meet the waste disposal demands and GHG emission requirements under different α-cut levels. The changes in the fuzzy confidence level have impacts on the waste allocation schemes, especially for the waste flow to the incinerator. The disposal cost differs across the three levels of 0.3, 0.5, and 0.7 for incinerator capacity constraint when the fuzzy confidence level of composting capacity constraint is equal to 0.5, implying the existence of the interaction between uncertainties in the incinerator and composting facility. Comparison between the waste management practices with and without considering GHG emission requirements indicates that the purchase of GHG emission credits would contribute about 10 % to the total cost, which would not be influenced significantly by the α-cut level.

The effectiveness of adsorbent agent from agricultural wastes and biomass to remove dye from aqueous solution was investigated. In this study, solution of methylene blue (MB) and two adsorbents, bark of cengal tree (Neobalanocarpus hepmii) and seed of red chili (Capsicum annuum), were tested. Experiments were performed with testing MB solution at 3-h interval and also testing with different quantities of adsorbent. In addition, the further study on characterization of adsorbent by Field Emission Scanning Electron Microscopy (FESEM) and Fourier Transform Infrared Spectroscopy (FTIR) was conducted in order to elucidate the properties and surface structure of the adsorbents. Analysis from UV-Vis spectroscopy showed that both adsorbents remove MB dye effectively and according to FESEM analysis due to the structure of the adsorbent were perforated and consist of polymer components. On the other hand, in FTIR perspective, the adsorption was successful because of the presence of carboxyl and carbonyl groups from both adsorbent that helps enhanced the process of adsorption.

Despite a contemporary interest in biochar application to agricultural fields to improve soil quality and long-term carbon sequestration, a number of potential side effects of biochar incorporation in field soils remain poorly understood, e.g., in relation to interactions with agrochemicals such as pesticides. In a field-based study at two experimental sites in Denmark (sandy loam soils at Risoe and Kalundborg), we investigated the influence of birch wood biochar with respect to application rate, aging (7–19 months), and physicochemical soil properties on the sorption coefficient, K d (L kg⁻¹), of the herbicide glyphosate. We measured K d in equilibrium batch sorption experiments with triplicate soil samples from 20 field plots that received biochar at different application rates (0 to 100 Mg ha⁻¹). The results showed that pure biochar had a lower glyphosate K d value as compared to soils. Yet, at the Kalundborg soils, the application of biochar enhanced the sorption of glyphosate when tested after 7–19 months of soil–biochar interaction. The relative enhancement effect on glyphosate sorption diminished with increasing biochar application rate, presumably due to increased mineral–biochar interactions. In the Risoe soils, potential biochar effects on glyphosate sorption were affected by a distinct gradient in soil pH (7.4 to 8.3) and electrical conductivity (0.40–0.90 mS cm⁻¹) resulting from a natural CaCO₃ gradient. Thus, glyphosate K d showed strong linear correlation with pH and EC. In conclusion, the results show that biochar, despite initially being a poor sorbent for glyphosate, can increase glyphosate sorption in soil. However, the effect of biochar on glyphosate sorption is depends on prevailing soil physicochemical properties.

The Cumberland Marsh Region (CMR), located on the coast of the Bay of Fundy, is a major feeding ground for waterfowl and contains significant coastal wetland systems. In this study, concentrations of lead (Pb) and arsenic (As) were assessed in the bottom sediments of various open water wetlands across the CMR, and gastropods were sampled from the same wetlands to assess bioaccumulation of these non-essential trace elements and the potential for transfer to higher trophic level species. It was predicted that gastropods would have higher concentrations of Pb and As from wetlands with higher concentrations of these elements in sediments. Although wetland sediments and gastropods had elevated Pb and As concentrations, in some cases above the Canadian Sediment Quality Guidelines for the protection of aquatic life, there were no significant correlations between sediment and gastropod trace element concentrations. Gastropod to sediment ratios of Pb and As concentrations were highest in the brackish wetlands, but overall, levels were not of toxicological concern. Wetland chemistries and gastropod physiologies are hypothesized to be driving factors in determining the level to which Pb and As will bioaccumulate and merit careful consideration when developing wetland management strategies.

It is important to understand the fate of Hg and Sb within the wastewater treatment process so as to examine potential treatment options and to ensure compliance with regulatory standards. The fate of Hg and Sb was investigated for an activated sludge process treatment works in the UK. Relatively high crude values (Hg 0.092 μg/L, Sb 1.73 μg/L) were observed at the works, whilst low removal rates within the primary (Hg 52.2 %, Sb 16.3 %) and secondary treatment stages (Hg 29.5 %, Sb −28.9 %) resulted in final effluent concentrations of 0.031 μg/L for Hg and 2.04 μg/L for Sb. Removal of Hg was positively correlated with suspended solids (SS) and chemical oxygen demand (COD) removal, whilst Sb was negatively correlated. Elevated final effluent Sb concentrations compared with crude values were postulated and were suggested to result from Sb present in returned sludge liquors. Kepner Tregoe (KT) analysis was applied to identify suitable treatment technologies. For Hg, chemical techniques (specifically precipitation) were found to be the most suitable whilst for Sb, adsorption (using granulated ferric hydroxide) was deemed most appropriate. Operational solutions, such as lengthening hydraulic retention time, and treatment technologies deployed on sludge liquors were also reviewed but were not feasible for implementation at the works.

To date, there is no compiled information for stormwater quality data intended for drinking water supply via managed aquifer recharge (MAR) making risk assessment of these schemes difficult. This study compiles hazards relevant to water recycling via MAR and calculates the associated 95th percentile values. The 95th percentiles of iron, turbidity, colour and faecal indicators exceeded the guideline values at all sites. Likewise, measured hazards for which 95th percentile values met drinking water guidelines (other metals (e.g. zinc), salinity (electrical conductivity) and nutrients including nitrate) did so at all sites. Considering a variety of climatic zones and catchment characteristics and the temporal variations typical in urban stormwater quality, there was a remarkable similarity in the 95th percentile concentrations for a suite of water quality hazards in urban stormwater. This is important in consideration of drinking water risk assessments and determining treatment requirements for potable use.

High serum concentrations of polychlorinated biphenyls (PCBs) have been reported previously among residents of Anniston, Alabama, where a PCB production facility was located in the past. As the second of two cross-sectional studies of these Anniston residents, the Anniston Community Health Survey: Follow-Up and Dioxin Analyses (ACHS-II) will yield repeated measurements to be used to evaluate changes over time in ortho-PCB concentrations and selected health indicators in study participants. Dioxins, non-ortho PCBs, other chemicals, heavy metals, and a variety of additional clinical tests not previously measured in the original ACHS cohort will be examined in ACHS-II. The follow-up study also incorporates a questionnaire with extended sections on diet and occupational history for a more comprehensive assessment of possible exposure sources. Data collection for ACHS-II from 359 eligible participants took place in 2014, 7 to 9 years after ACHS.

This study evaluates the present day effects of air pollutants emitted from an iron sintering plant near Wawa (Ontario, Canada) decades ago (1939–1998). During smelting and refining of iron ore, gaseous sulfur-rich emissions and large amounts of metal-containing (iron oxides) particulate materials were released in to the air, and eventually settled onto vegetation and soil cover. We test the feasibility of using magnetic measurements to investigate and quantify the soil pollution resulting from the sintering plant. Surface and subsurface magnetic susceptibility measurements, as well as various magnetic mineral properties, have been collected in a scheme designed to mimic the previously determined pollutant contamination zones. A total of 50 sites were sampled (with a sampling grid of 250 m) within and around the smelter kill zone to the northwest of Wawa. Results were plotted on cross sections perpendicular (X-X′) and parallel (Y-Y′) to the dominant wind direction in order to investigate magnetic properties of the soil samples as a function of both wind direction and distance from the source. Samples located in Rao and LeBlanc’s (The Bryologist 70:141–17, 1967) pollution zones 1 and 2 typically have κ ᵢₙ₋ₛᵢₜᵤ values >120 × 10⁻⁵ SI, while the zone 3 and 4 results are <100 × 10⁻⁵ SI. Magnetic susceptibility enhancements at depths of 5–10 cm were found to be related to the presence of magnetic spherules (fly-ashes) at sites on the wind-parallel Y-Y′ profile in the previously defined kill zone. An estimated minimum migration rate of iron-rich particulates is calculated for coarse sand and silt/clay sites as 0.24 and 0.1 cm/year, respectively.

This work focuses on the influence of different parameters on the efficiency of steel slag carbonation in slurry phase under ambient temperature. In the first part, a response surface methodology was used to identify the effect and the interactions of the gas pressure, liquid/solid (L/S) ratio, gas/liquid ratio (G/L), and reaction time on the CO₂ removed/sample and to optimize the parameters. In the second part, the parameters’ effect on the dissolution of CO₂ and its conversion into carbonates were studied more in detail. The results show that the pressure and the G/L ratio have a positive effect on both the dissolution and the conversion of CO₂. These results have been correlated with the higher CO₂ mass introduced in the reactor. On the other hand, an important effect of the L/S ratio on the overall CO₂ removal and more specifically on the carbonate precipitation has been identified. The best results were obtained L/S ratios of 4:1 and 10:1 with respectively 0.046 and 0.052 gCO₂ carbonated/g sample. These yields were achieved after 10 min reaction, at ambient temperature, and 10.68 bar of total gas pressure following direct gas treatment.