The natural (S₀) and chemically modified Phanerochaete chrysosporium including the methylation of amino groups (S₁), acetylation of hydroxyl groups (S₂), lipid removal (S₃), esterification of carboxyl groups (S₄), and base hydrolysis (S₅) were characterized, and their sorption for phenanthrene (PHE) was investigated. The sorption isotherm of PHE on natural biomasses was apparently linear, while it was nonlinear for the modified ones. The partition coefficient (K d) describing the sorption affinity of PHE by biomasses followed the order of S₀ (9.24 L g⁻¹) > S₅ (8.94 L g⁻¹) > S₁ (7.13 L g⁻¹) > S₂ (6.97 L g⁻¹) > S₃ (6.38 L g⁻¹) > S₄ (3.51 L g⁻¹) and decreased as temperature increased. The PHE adsorption fitted well to the pseudo-second-order kinetic model, and the sorption capacity was in the order of S₅ (2041.5 μg g⁻¹) > S₀ (1768.8 μg g⁻¹) > S₂ (1570.9 μg g⁻¹) > S₁ (1552.9 μg g⁻¹) > S₃ (1346.4 μg g⁻¹) > S₄ (991.0 μg g⁻¹). Moreover, the π–π and electron donor–acceptor interactions may govern PHE sorption which processed spontaneously and exothermally. The natural and modified biomasses, especially the base hydrolysis treated ones, were economical and effective biosorbents for PHE removal.

A novel isolated bacterium Rhodococcus sp. YSPW03 was able to reduce high concentrations (up to 700 mg L⁻¹) of perchlorate using acetate as electron donor. Perchlorate reduction rate increased from 2.90 to 11.23 mg L⁻¹ h⁻¹ with increasing initial acetate concentration from 100 to 2000 mg L⁻¹, leading to complete removal of perchlorate (100 mg L⁻¹) within 9 h. The bacterium also promoted complete reduction of high perchlorate concentrations (500 and 700 mg L⁻¹) at 2000 mg L⁻¹ of acetate within 48 and 96 h, respectively. Under semi-continuous reactor operation, efficient reduction on varied perchlorate concentrations (80–700 mg L⁻¹) was performed by the bacterium in presence of acetate (600–6000 mg L⁻¹) over 140 days. The highest perchlorate reduction rate of 280 mg L⁻¹ day⁻¹ was observed with an initial perchlorate concentration of 570 mg L⁻¹ at day 34. Dissolved chloride ions of 1000 mg L⁻¹ in the semi-continuous reactor (SCR) completely inhibited the biological perchlorate reduction. The findings of this study will help improve the perchlorate bioreactor design and determine the optimal conditions to maximize the perchlorate reduction efficiency.

Ammonia emissions at the national level are frequently estimated by applying the emission inventory approach, which includes the use of emission factors, which are difficult and expensive to determine. Emission factors are therefore the subject of estimation, and as such they contribute to inherent uncertainties in the estimation of ammonia emissions. This paper presents an alternative approach for the prediction of ammonia emissions at the national level based on artificial neural networks and broadly available sustainability and economical/agricultural indicators as model inputs. The Multilayer Perceptron (MLP) architecture was optimized using a trial-and-error procedure, including the number of hidden neurons, activation function, and a back-propagation algorithm. Principal component analysis (PCA) was applied to reduce mutual correlation between the inputs. The obtained results demonstrate that the MLP model created using the PCA transformed inputs (PCA-MLP) provides a more accurate prediction than the MLP model based on the original inputs. In the validation stage, the MLP and PCA-MLP models were tested for ammonia emission predictions for up to 2 years and compared with a principal component regression model. Among the three models, the PCA-MLP demonstrated the best performance, providing predictions for the USA and the majority of EU countries with a relative error of less than 20 %.

Toxic Microcystis species are the main bloom-forming cyanobacteria in freshwaters. It is imperative to develop efficient techniques to control these notorious harmful algal blooms (HABs). Here, we present a simple, efficient, and environmentally safe algicidal way to control Microcystis blooms, by using intermediate carboxylic acids from the tricarboxylic acid (TCA) cycle. The citric acid, alpha-ketoglutaric acid, succinic acid, fumaric acid, and malic acid all exhibited strong algicidal effects, and particularly succinic acid could cause the rapid lysis of Microcystis in a few hours. It is revealed that the Microcystis-lysing activity of succinic acid and other carboxylic acids was due to their strong acidic activity. Interestingly, the acid-lysed Microcystis cells released large amounts of phycocyanin, about 27-fold higher than those of the control. On the other hand, the transcription of mcyA and mcyD of the microcystin biosynthesis operon was not upregulated by addition of alpha-ketoglutaric acid and other carboxylic acids. Consider the environmental safety of intermediate carboxylic acids. We propose that administration of TCA cycle organic acids may not only provide an algicidal method with high efficiency and environmental safety but also serve as an applicable way to produce and extract phycocyanin from cyanobacterial biomass.

Several studies have reported that the chewing habit of smokeless tobacco (SLT) has been associated with oral cancer. The aim of the present study was to evaluate the trace levels of lead (Pb) in biological samples (blood, scalp hair) of oral cancer patients and referents of the same age group (range 30–60 years). As the concentrations of Pb are very low in biological samples, so a simple and efficient ionic liquid-based microextraction in a single syringe system has been developed, as a prior step to determination by flame atomic absorption spectrometry. In this procedure, the hydrophobic chelates of Pb with ammonium pyrrolidinedithiocarbamate (APDC) were extracted into fine droplets of 1-butyl-3-methylimidazolium hexafluorophosphate [C₄MIM][PF₆] within a syringe while using Triton X-114 as a dispersant. Factors influencing the microextraction efficiency and determination, such as pH of the sample, volume of [C₄MIM][PF₆] and Triton X-114, ligand concentration, and incubation time, were studied. To validate the proposed method, certified reference materials were analyzed and the results of Pb²⁺ were in good agreement with certified values. At optimum experimental values of significant variables, detection limit and enhancement factor were found to be 0.412 μg/L and 80, respectively. The coexisting ions showed no obvious negative outcome on Pb preconcentration. The proposed method was applied satisfactorily for the preconcentration of Pb²⁺ in acid-digested SLT and biological samples of the study population. It was observed that oral cancer patients who consumed different SLT products have 2–3-fold higher levels of Pb in scalp hair and blood samples as compared to healthy referents (p < 0.001). While 31.4–50.8 % higher levels of Pb were observed in referents chewing different SLT products as compared to nonconsumers (p < 0.01).

There is scarcity in literature in regards to the exact levels of such compounds in the Middle Eastern region including Jordan. This study was conducted to measure the presence and levels of perfluoroalkyl substances (PFASs) (perfluoroocane sulfonate (PFOS) and perfluorooctanoic acid (PFOA)) in human milk and local fresh cow milk in northern Jordan and also to investigate the relationship between levels of PFASs and some sociodemographic characteristics of breastfeeding mothers and their infants as well as usage of Teflon kitchenware products. Seventy-nine milk samples were collected from breastfeeding women and 25 samples from local fresh cow milk in northern Jordan. Levels of PFOS and PFOA were liquid/liquid extracted (LLE) by acetone followed by purification on an Oasis hydrophilic-lipophilic balance (HLB) solid-phase extraction (SPE). Separations and detections were performed by liquid chromatography-tandem mass spectrometry. Limits of quantitation (LOQs) were 10 ng/L for both PFOA and PFOS. The measured concentrations ranged between non-detectable (ND) and 178 ng/L for PFOS and between 24 and 1120 ng/L for PFOA in human milk and between ND-178 ng/L and LOQ-160 ng/L in fresh cow milk, respectively. Median concentrations of PFOS in human milk samples from Jordan in this study were lower than those found in a recent study from Italy. Moreover, mean concentrations of PFOA and PFOS were significantly higher in milk samples provided by older women. Also, mean concentrations of PFOA was much higher in multiparas and those who have younger infants. The mean rank of PFOA was twice as high in the milk of women who had older Teflon products in kitchen compared to those who had relatively new Teflon products.

The sensitivity of two tomato (Solanum lycopersicum L.) cultivars, Rechaiga II and De Colgar, to 50, 80, and 100 ppb ozone (O₃) exposures was assessed in fumigation chamber, during 4 h per day over a period of 7 days. The Rechaiga II variety was shown to be sensitive to the dose of 50 ppb, showing chlorotic spots on the adaxial leaf surface and alterations of some physiological parameters. During 1-week fumigation, ozone caused a decrease in stomatal conductance, chlorophylls a and b, total chlorophylls, and carotenoids, although soluble sugars and membrane integrity were significantly increased in fumigated plants compared to controls. This trend was similar for the three pollutant doses used in fumigation. The De Colgar tomato remained asymptomatic.

This study aims to evaluate possible toxic effects of oil and other contaminants from oilfield-produced water from oil exploration and production, on seed germination, and seedling development of sunflower (Helianthus annuus L.). In comparison, as treated by electroflocculation, oilfield-produced water, with lower oil and organic matter content, was also used. Electroflocculation treatment of oilfield-produced water achieved significant removals of chemical oxygen demand (COD) (94 %), oil and grease (O&G) (96 %), color (97 %), and turbidity (99 %). Different O&G, COD, and salt levels of untreated and treated oilfield-produced water did not influence germination process and seedling biomass production. Normal seedlings percentage and vigor tended to decrease more intensely in O&G and COD levels, higher than 337.5 mg L⁻¹ and 1321 mg O₂ L⁻¹, respectively, using untreated oilfield-produced water. These results indicate that this industrial effluent must be treated, in order to not affect adversely seedling development. This way, electroflocculation treatment appears as an interesting alternative to removing oil and soluble organic matter in excess from oilfield-produced water improving sunflower’s seedling development and providing a friendly environmental destination for this wastewater, reducing its potential to harm water resources, soil, and biota.

This paper provides data on the occurrence of selected human pharmaceuticals (carbamazepine, clofibric acid, diclofenac, fenofibrate, fenoprofen, gemfibrozil, ibuprofen, ketoprofen, and naproxen) including steroid hormones (17β-estradiol, 17α-ethinylestradiol, and estrone) in influents/effluents to/from the four principal wastewater treatment plants (WWTPs) serving the city of Rome (Italy), in two different sampling campaigns. Target compounds were also analyzed in the receiving River Tiber and River Aniene. Analytical determination was carried out by LC-MS/MS after sample cleanup and concentration by off-line solid-phase extraction (SPE). The aim of the study was to increase the information currently available on the presence and persistence of pharmaceuticals in Italian urban wastewaters and to evaluate the environmental impact of the pharmaceutical residues discharged through effluents into the receiving rivers. Results indicated that after the treatment processes, most of pharmaceuticals were not completely eliminated, as average removal efficiencies were in the 14–100 % wide range during both sampling periods, with higher yields in spring than in winter. Levels detected in overall samples ranged from 5 to 2,230 ng/L in influents and from 5 to 1,424 ng/L in effluents. Carbamazepine, diclofenac, ibuprofen, and gemfibrozil showed the highest persistence to removal. Concentrations in the receiving waters were about one order of magnitude lower than in effluents, with a tendency to increase progressively through the urban tract of the river. Finally, an environmental risk analysis showed that carbamazepine, gemfibrozil, and estrone can pose a high risk at the concentrations detected in effluents and a medium risk in rivers, highlighting their potential hazard for the health of the aquatic ecosystem.