A greenhouse experiment was accomplished to investigate the feasibility of excess sludge modified by coal fly ash pretreatment and γ-ray irradiation in soil application for cultivation of Artemisia ordosica. The results showed that modified excess sludge provided a positive effect on the growth of Artemisia ordosica. The modified excess sludge and aeolian sandy soil at the volume ratio of 1:2 was optimal, and nutrient concentrations of Artemisia ordosica reached the highest. In the aeolian sandy soil, the bio-concentration factor values of most heavy metals were less than 1.0 except for Cu, Zn, and Ni. The average bio-concentration factor values of heavy metals in Artemisia ordosica increased in a sequence of Mo < Cd < Fe < V < Cr < Co < Mn < Pb < Cu < Zn < Ni for all samples. Artemisia ordosica could be used to decrease the bioavailability and eco-toxicity of Ni, V, and Mo in all cultivation experiments of artificial soil, and Artemisia ordosica could also reduce the bioavailability and eco-toxicity of Cu, Cd, Cr, and Mn in the artificial soil of modified excess sludge and aeolian sandy soil at the volume ratio of 1:2.

Drainage filters using porous granular material constitute new innovative technologies for remediating phosphorus (P) from agricultural tile drainage water. In drainage filters where convective velocities are often high, we hypothesize that intragranular diffusion may affect solute transport depending on filter characteristics and flow rate. This was investigated for six drainage filter materials (Leca, Filtralite-P®, granulated limestone, crushed seashells, calcined diatomite earth (CDE), and a poorly ordered Fe oxide aggregate (CFH)) conducting a tritium (³H₂O) tracer experiment at low (0.26 cm h⁻¹), medium (23 cm h⁻¹), and high (41 cm h⁻¹) flux densities. The filter materials differed widely with respect to grain-size distribution (D ₅₀ from 1.6 to 3.3 mm), uniformity coefficient (1.7 to 2.2), particle density (1.75 to 2.76 g cm⁻³), bulk density (0.34 to 1.46 g cm⁻³), and water-filled porosity (0.39 to 0.73 cm³ cm⁻³). Measurements of specific surface area (SSA) included both SSABET and SSAEGME to ensure inclusion of the intragranular microporosity, not accounted by N₂-BET. SSA varied widely across methods and allowed the differentiation of filters according to the significance of the intragranular porosity. Tritium transport varied from approximately equilibrium transport at all flow rates in Leca, Filtralite-P®, and limestone, to progressive non-equilibrium transport as flow rate increased in Seashells, CDE, and CFH. In general, the filter materials were highly variable in hydro-physical properties. Filters with (approximately) equilibrium transport were, however, all characterized by low specific surface areas. The non-equilibrium transport was explained by an intragranular diffusion in filters with larger specific surface area (Seashells, CDE, and CFH).

The study was developed at the Municipality of São Gabriel do Oeste, State of Mato Grosso do Sul, Brazil, where were performed analyses of water samples, including physical and chemical aspects, obtained through Hanna multi-parameter probe into four different parts of the study area. Landsat satellite 8 (L8) and unmanned aerial vehicle (UAV) was also used to generate vegetation indices, using the visible spectral range for both types of images and normalized difference vegetation index (NDVI) just for L8. Later, these ratios were correlated to chlorophyll a that has a key role in photosynthesis. Regarding the physical and chemical parameters, the collection point 2 was the most differed to the others; this may have happened to be a dam with little flow in an eutrophication process. Through the water absorbance curve in the visible wavelengths, it is possible to estimate comparatively water body that has larger amounts of dissolved materials in the water. There was a high correlation between vegetation indices generated from aerial photographs and L8 image, with chlorophyll a extracted from water in the laboratory. In this sense, they are likely to use to forecast future scenarios. It is suggested the use of aerial photographs of UAVs for monitoring the environmental quality of small water bodies, considering its high spatial and temporal resolution.

A pilot scale micro-flocculation and dynasand filtration process was used to pretreat the petrochemical secondary effluent. The suspended solids (SS) and the dissolved organic matter (DOM) removal characteristics were investigated. The results showed that the optimized poly aluminum ferric chloride (PFAC) dosage was 10 mg/L during the experiment. In this dosage period, the SS removal rate was as high as 50.58 % with the effluent SS of 15.38 mg/L when the influent SS was 33.53 mg/L. The COD removal rate was 10.42 %. The DOM fraction with large apparent molecular weight (MW) higher than 3 k was removed more significantly than that of small molecular DOM. Resin fractionation showed that the micro-flocculation and dynasand filtration process could preferentially remove the hydrophobic neutrals (HON) and hydrophobic acids (HOA) of DOM, so it could be suitable as the pretreatment unit. When oxidized by catalytic ozonation, the ozone consumption of COD removal for filtrated effluent was 1.2 g-O₃/g-COD while it was 1.6 g-O₃/g-COD for untreated petrochemical secondary effluent, saving 25 % of ozone consumption. The micro-flocculation and dynasand filtration is a suitable pretreatment process for petrochemical secondary effluent, especially when the subsequent unit is the catalytic ozonation process.

Given that drugs and their degradation products are likely to occur as concoctions in wastewater, the degradation of a mixture of two nonsteroidal anti-inflammatory drugs (NSAIDs), diclofenac (DCF) and naproxen (NPX), was investigated by solar photolysis and titanium dioxide (TiO₂)-mediated solar photocatalysis using an immersion-well photoreactor. An equimolar ratio (1:1) of both NSAIDs in distilled water, drinking water, and river water was subjected to solar degradation. Solar photolysis of the DCF and NPX mixture was competitive particularly in drinking water and river water, as both drugs have the ability to undergo photolysis. However, the addition of TiO₂ in the mixture significantly enhanced the degradation rate of both APIs compared to solar photolysis alone. Mineralization, as measured by chemical oxygen demand (COD), was incomplete under all conditions investigated. TiO₂-mediated solar photocatalytic degradation of DCF and NPX mixtures produced 15 identifiable degradants corresponding to degradation of the individual NSAIDs, while two degradation products with much higher molecular weight than the parent NSAIDs were identified by liquid chromatography mass spectrometry (LC-MS) and Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS). This study showed that the solar light intensity and the water matrix appear to be the main factors influencing the overall performance of the solar photolysis and TiO₂-mediated solar photocatalysis for degradation of DCF and NPX mixtures.

Indoor dust samples were collected from 40 homes in Kocaeli, Turkey and were analyzed simultaneously for 14 polybrominated diphenyl ethers (PBDEs) and 16 poly aromatic hydrocarbons (PAHs) isomers. The total concentrations of PBDEs (Σ₁₄PBDEs) ranged from 29.32 to 4790 ng g⁻¹, with a median of 316.1 ng g⁻¹, while the total indoor dust concentrations of 16 PAHs (Σ₁₆PAHs) extending over three to four orders of magnitude ranged from 85.91 to 40,359 ng g⁻¹ with a median value of 2489 ng g⁻¹. Although deca-PBDE products (BDE-209) were the principal source of PBDEs contamination in the homes (median, 138.3 ng g⁻¹), the correlation in the homes was indicative of similar sources for both the commercial penta and deca-PBDE formulas. The PAHs diagnostic ratios indicated that the main sources of PAHs measured in the indoor samples could be coal/biomass combustion, smoking, and cooking emissions. For children and adults, the contributions to ∑₁₄PBDEs exposure were approximately 93 and 25 % for the ingestion of indoor dust, and 7 and 75 % for dermal contact. Exposure to ∑₁₆PAHs through dermal contact was the dominant route for both children (90.6 %) and adults (99.7 %). For both groups, exposure by way of inhalation of indoor dust contaminated with PBDEs and PAHs was negligible. The hazard index (HI) values for BDE-47, BDE-99, BDE-153, and BDE-209 were lower than the safe limit of 1, and this result suggested that none of the population groups would be likely to experience potential health risk due to exposure to PBDEs from indoor dust in the study area. Considering only ingestion + dermal contact, the carcinogenic risk levels of both B2 PAHs and BDE-209 for adults were 6.2 × 10⁻⁵ in the US EPA safe limit range while those for children were 5.6 × 10⁻⁴ and slightly higher than the US EPA safe limit range (1 × 10⁻⁶ and 1 × 10⁻⁴). Certain precautions should be considered for children.

Bisphenol A (BPA) is one of the recalcitrant contaminants that are detected in drinking water sources, as the conventional water treatment plant is incapable of removing it completely. This study was conducted to explore the performance of ultrafiltration (UF) membrane system for the BPA removal in which BPA was spiked in water sample collected from a treatment plant. The effects of process conditions that may influence the removal and flux performance of the membrane including operating pressure, feed pH and BPA concentration, and backwash cleaning were investigated. The results showed that an applied pressure of 1 bar was the optimum pressure for achieving good balance of BPA removal (95 %) and water flux (109 L m⁻² h⁻¹) compared to operating pressure of 0.5 and 1.5 bar. The variation of feed pH showed significant impact on BPA elimination with the highest rejection (90 %) achieved at pH 7 while the lowest removal (20 %) at pH 10. BPA concentration had no significant impact on BPA removal as high removal rate (>95 %) was observed regardless of feed concentration (between 10 and 100 μg L⁻¹). The normalized flux showed decreasing trend with filtration cycle due to increased membrane resistance of BPA adsorption onto the membrane. The membrane cleaning via backwash was able to recover 90 % BPA removal even after three consecutive cycles of filtration. This indicated the promising performance of UF membrane system for industrial water treatment.

It is traditionally accepted that urban vegetation contributes to improve air quality by intercepting and retaining the particulate matter. Although the mitigating role of plants has been recognized by several studies, the role of individual species is still poorly understood. This is particularly important in cities like Santiago (Chile), which has high levels of atmospheric particulate and also has high plant species diversity. In this study, we evaluated the retention of atmospheric particles by three widely distributed ornamental species (Nerium oleander, Pittosporum tobira, and Ligustrum lucidum) in Santiago. For this proposal, we took leaf samples in different sampling points across the city which vary in their concentration of atmospheric particulate. Samples were taken 12 and 16 days after a rainfall episode that washed the leaves of plants in the sampling sites. In the laboratory, leaves were washed to recover the surface retained particles that were collected to determine its mass gravimetrically. With this information, we estimated the foliar retention (mass of particulate matter retained in the foliar surface) and daily retention efficiency (mass of particulate matter retained in the foliar surface per day). We found that foliar retention and daily retention efficiency varied significantly between the studied species. The leaves of N. oleander retained 8.2 g m⁻² of particulate matter on average, those of P. tobira 6.1 g m⁻², and those of L. lucidum 3.9 g m⁻²; meanwhile, the daily retention efficiencies of particulate matter were 0.6, 0.4, and 0.3 g m⁻² day⁻¹ for N. oleander, P. tobira, and L. lucidum, respectively. These results suggest that the studied species retain atmospheric particulate matter differentially in Santiago. These results can be attributed to differences on leaf surface characteristics. The recognition of the most efficient species in the retention of the atmospheric particulate matter can help to decide which species can be used to improve the air quality in the city.