Effective treatment of dairy wastewater with efficient removal of antibiotic-resistant bacteria (ARB) is a great challenge for reuse of treated wastewater. Antibiotics are widely used in human and veterinary medicine, and antibiotics misuse has led to occurrence and spread of antibiotic-resistant bacteria (ARB). Reuse of treated wastewater for irrigation is a solution to deal with water shortage in developing countries. One of the major problems of treated wastewater reuse is the possible presence of ARB. Removal of ARB from dairy wastewater using a full-scale hybrid constructed wetland (CW) at Miyagi Prefecture, Japan, was studied. It was well-defined that hybrid CW caused a complete removal of ampicillin-, gentamicin-, kanamycin-, and streptomycin-resistant bacteria resulting in an effluent free of these resistant strains. Additionally, a significant decrease in the number of vancomycin-RB was definite with a final 3.2 log unit decrease in the effluent. This study addressed the remarkable efficiency of a full-scale hybridized CW in Kawatabi, Field Science Center, Tohoku University. It decreased the output of organic matter (COD), total suspended solids (SS), and ammonia-nitrogen. The performance of CW for the removal ARB from dairy wastewater was efficient to minimize the release of these contaminants into the environment and avoid the spread of antibiotic resistance with safe discharge and reuse of treated wastewater. Finally, the current study represents the first report about the assessment of ARB removal during treatment of dairy wastewater using CW.

Quaternary alkyl ammonium compounds (QAACs) are produced in large quantities for use as surfactants and disinfectants and also found in soils, sediments, and surface waters, where they are potentially involved in the selection of antibiotic resistance genes. Micelle formation influences fate and effects of QAACs. The critical micelle concentration (CMC) of six homologs of benzylalkylammonium chlorides (BAC) was determined in deionized water, 0.01 M CaCl₂ solution, and aqueous soil extracts, using both spectrofluorometric and tensiometric methods. Additionally, eight organic model compounds were employed at concentrations of 15 mg C L⁻¹ as background solutes in order to test the effect of dissolved organic carbon (DOC) on CMCs. Results found CMCs decreased with an increasing length of the alkyl chain from 188 mM for BAC-C8 to 0.1 mM for BAC-C18. Both methods yielded similar results for measurements in water and CaCl₂ solution; however, the spectrofluorescence method did not work for soil extracts due to fluorescence quenching phenomena. In soil extracts, CMCs of BAC-C12 were reduced below 3.7 mM, while the CMC reduction in soil extracts was less pronounced for BAC-C16. Besides ionic strength, molecular structures of BACs and dissolved organic compounds also affected the CMC. The number of carboxyl groups and small molecular weights of the DOC model compounds reduced the CMCs of BAC-C12 and BAC-C16 at pH 6. This study highlights that CMCs can be surpassed in soil solution, pore waters of sediments, or other natural waters even at (small) concentrations of QAACs typically found in the environment.

Cataract is the first cause of blindness and the major cause of visual impairment worldwide. Under conditions of global warming, researchers have begun to give attention to the influence of increasing temperature on cataract patients. Our paper aimed to investigate the association between extreme heat and hospital admissions for cataract in Hefei, China. Based on data from the New Rural Cooperative Medical System and National Meteorological Information Center, we used a generalized additive model and a distributed lag nonlinear model to examine the relationship between extreme heat and hospitalizations for cataract, with consideration of cumulative and lagged effects. When current mean temperature was above 28 °C, each 1 °C rise was associated with a 4% decrease in the number of cataract admissions (RR = 0.96, 95% CI = 0.94–0.98). The cumulative relative risk over 11 days of lag was the lowest, which indicated that every 1 °C increase in mean temperature above 28 °C was associated with a 19% decrease in the number of hospital admissions for cataract (RR = 0.81, 95% CI = 0.75–0.88). In subgroup analyses, the negative association between extreme heat and hospital admissions for cataract was stronger among patients who were not admitted to provincial-level hospitals. In conclusion, this paper found that extreme heat was negatively associated with cataract hospitalizations in Hefei, providing useful information for hospitals and policymakers.

The aim of this study was to evaluate the effect of pretreatment on the phytotoxicity and leaching of nitrogen and phosphorus in biosolids from anaerobic digestion in silty loam soil. Soil columns filled with silty loam soil and biosolids (BS) stabilized by conventional (CAD) and advanced (AAD) anaerobic digestion were installed. AAD consisted of the application of sequential pretreatments: ultrasound followed by a low thermal process. The BS loads were equivalent to 30 ton/ha (CAD30 and AAD30) and 90 ton/ha (CAD90 and AAD90), and the soil columns were watered with 29 mL/day of distilled water. Phytotoxicity was evaluated by germination and root growth inhibition and by the germination index (GI) of Triticum aestivum, Lactuca sativa, and Raphanus sativus seeds. Nitrogen leaching varied from 0 to 9 mg/week, while phosphate leaching did not exceed 0.01 mg/week. The nutrient leaching rate depended on the BS application rate and not on the use of pretreatment (p < 0.05). Regarding phytotoxicity, BS application presented a tendency to attenuate the inhibition caused by the silty loam soil, with GI values ranging from 31 to 50%, 62 to 63%, and 70 to 82% for L. sativa, R. sativus, and T. aestivum, respectively.Graphical abstract

Significant levels of polycyclic aromatic hydrocarbons (PAHs) were detected in lakes. The competition between algae would be disturbed by PAHs resulted in variations of algal growth. For controlling the cyanobacterial blooms, it is important to understand this disturbed competition between Microcystis aeruginosa and other algae. A 6-day cultivation experiment was designed to investigate the responses of M. aeruginosa to PAHs in presence of green algae. A popular green alga Chlorella pyrenoidosa was used as a representative of green algae, and phenanthrene and pyrene were selected as representatives of PAHs. The results showed that M. aeruginosa outcompeted C. pyrenoidosa under PAH contamination, and PAHs and M. aeruginosa significantly inhibited the survival of C. pyrenoidosa. PAHs disturbed the growth of algae by influencing photosynthetic pigments and phycobiliproteins, and the different alteration of Fᵥ/Fₘ ratios implied that shifted algal community composition would be induced by PAHs. The Fᵥ/Fₘ of the two algal mixture and individual C. pyrenoidosa was significantly negatively correlated with phenanthrene levels. However, there were no significant correlations between the Fᵥ/Fₘ of M. aeruginosa and the exposure levels of phenanthrene or pyrene. Remarkably, the Fᵥ/Fₘ significantly increased in M. aeruginosa at 0.15 mg L⁻¹ pyrene, suggesting that PSII resistance to pyrene was enhanced in M. aeruginosa. Our results pointed out an increasing frequency and intensity of cyanobacterial blooms could be induced by PAHs in contaminated waters.

The disposal of carmine cochineal and caramel IV dyes into the environment through effluents generated in the industry is constant. However, studies on the toxicity caused to terrestrial plants and aquatic organisms are limited for the carmine dye and non-existent for the caramel dye. The aim of this study was to evaluate the cytotoxicity and genotoxicity of color additives in meristematic Allium cepa cells from 22.50 to 0.225 mL/L for the carmine cochineal dye and from 18.00 to 0.045 mL/L for the caramel IV dye. In A. cepa, we considered the concentration of each dye in the effluent after the usual biological degradation carried out in the industry. Data were tested by using analysis of variance (one-way ANOVA), and the mean values were compared by using the Scott-Knott test with a significance of 0.05. Cochineal dye at concentrations from 22.50 to 2.81 mL/L and caramel dye at concentrations from 18.00 to 1.125 mL/L were cytotoxic. Cochineal dye was not genotoxic. Caramel concentrations 2.25 and 0.09 mL/L were genotoxic. The toxicity of each dye was also evaluated against Artemia salina at concentrations from 1000 to 0.97 ppm, determining the LC₅₀. The analyzed concentrations were defined based on the standard protocol for checking the mortality rate in brine shrimp. Concentration that causes mortality of 50% larvae was calculated based on the equation of the line obtained by linear regression. The additives were very toxic to A. salina with LC₅₀ = 1.72 ppm for carmine additive and LC₅₀ = 3.88 ppm for caramel. The dyes evaluated in this study indicate the potential to cause damage to organisms in the environment.

Soil is the support medium for the development of several activities; however, improperly used soils can become a serious environmental issue. The aim of the current study is to determine the concentration of chemical elements in soil used as landfill in Southern Brazil. Samples were collected in different soil profiles and depths and analyzed based on the X-ray fluorescence technique. Results have indicated changes in cadmium and chromium concentrations, regardless of the collection depth. The presence of iron oxides/hydroxides and 1:1 low CEC kaolinite clay in the samples may have contributed to the translocation of these elements to the underground environment. Thus, the adopted technique was efficient and enabled identifying changes in the concentrations of the investigated elements, which can be associated with their translocation through soil profile (in depth), as well as in comparing such concentrations to the ones set by the current legislation.

Using solely an optical remotely sensed dataset to obtain an accurate thematic map of land use and land cover (LU/LC) is a serious challenge. The dataset fusion of multispectral and panchromatic images play a big role and provide an accurate estimation of LU/LC map simply because using a dataset from different spectrum portions with different spatial and spectral characteristics will improve image classification. For this study, the Landsat operational land imager multispectral and panchromatic images were adopted. This study aimed to investigate the effectiveness of using a panchromatic highly spatial resolution to refine the methodology for LU/LC mapping in Baghdad city, Iraq, by performing a comparison of classifications using different algorithms on multispectral and fused images. Different classification algorithms were employed to classify the data set; minimum distance (MD) and the maximum likelihood classifier (MLC). A suitable classification method was proposed to map LU/LC based on the outcome results. The result evaluation was conducted by applying a confusion matrix. An overall accuracy of a fused image using a principal component-based spectral sharpening algorithm and classified by the MLC classifier reveals the highest accurate results with an overall accuracy and kappa coefficient of 98.90% and 0.98, respectively. Results showed that the best methodology for LU/LC mapping of the study area is found from fusion of multispectral with panchromatic images via principal component-based spectral algorithm with MLC approach for classification.

The purpose of this research was to use pyrrhotite ash, a residue from the phosphate industry, as an adsorbent material for the removal of reactive red 141 (RR141) dye from aqueous solution. The collected pyrrhotite ash was characterized by X-ray diffraction (XRD), scanning electron microscopy combined with energy-dispersive X-ray analysis (SEM-EDAX), Fourier transform-infrared spectroscopy (FTIR), and pHₚzc. In batch assays, diverse operating parameters impacting the dye removal were scrutinized such as pH, contact time, initial RR141 concentration, temperature, and pyrrhotite ash dose. The equilibrium of adsorption was obtained after 60 min contact time, and 97% of RR141 dye was adsorbed at ambient temperature. The isotherm of Langmuir and the pseudo-second-order kinetic model yield a suitable fit for the obtained batch experimental data; thermodynamic parameter analysis reveals the spontaneous, exothermic aspect of adsorption. Fixed bed column experiments were also tested to probe the effectiveness of pyrrhotite ash for applications in continuous mode. The breakthrough curve was described by the models of Yoon–Nelson and Thomas.

The present study evaluated the relationship between estrogenic hormone concentrations (17α-ethinylestradiol and 17β-estradiol) in surface waters in the Metropolitan Area of São Paulo (Brazil) and environmental variables. Four sampling stations were monitored ranging from a protected area to streams discharging human effluent in and around Billings Reservoir. Four sampling campaigns were carried out in each seasonal period: dry and wet. Samples for hormone analysis (in ng L⁻¹) were concentrated (1000×) using solid-phase extraction C₁₈ cartridges and analyzed by liquid chromatography coupled to quadrupole mass spectrometry detection, with 100 ng L⁻¹ limit of quantification. Water temperature, pH, electrical conductivity (EC), and total dissolved solids were determined in situ; total phosphorus and Sinapis alba bioassays were performed subsequently. Reservoir active capacity (AC) and precipitation were also obtained. Estrogenic hormone concentrations were always below limit of quantification at pristine site; at the other sampling stations, 17β-estradiol concentrations varied from below limit of quantification to 1720 ng L⁻¹ and 17α-ethinylestradiol from below limit of quantification to 1200 ng L⁻¹, with the highest concentrations found in the streams discharging into the reservoir. These streams showed higher Pearson’s correlation between 17α-ethinylestradiol, total phosphorus, and electrical conductivity when compared with reservoir stations. Germination index and EC presented negative correlation (Pearson’s r = − 0.61), denoting a phytotoxicity increase with EC increment. AC influenced the dilution of pollutants and showed negative correlations with total phosphorus (Pearson’s r = −0.56). These results highlight the relevance of including streams in water-monitoring programs, since they are important pollutants loads into watersheds.