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1.
Chemosphere ; 307(Pt 4): 135996, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35970214

ABSTRACT

One of the environmental effects of COVID 19 is the contamination of ecosystems with antibiotics due to their high consumption to treat this disease. Many years ago, the distribution of antibiotics including azithromycin (Azi) in wastewater treatment plants in Bushehr city, seawater, and sediment of the Persian Gulf has been investigated. As Azi has been prescribed to COVID 19 patients, contamination of the environment with this drug can also be assumed. Thus, we decided to examine this hypothesis by repeating our previous study during COVID 19 period. We collected wastewater samples from influent, effluent, and different units of three wastewater treatment plants (WWTPs) including one municipal WWTP (Plant A) and two hospital-WWTPs (Plant B and C). Seawater and adjusted sediments were gathered from 8 stations located in the Persian Gulf in two seasons to evaluate the special and temporal variation. The results showed a huge growth of Azi pollution in all studied matrixes. The mean Azi values in the influent of Plant A, B, and C were 145 ng/L, 110 ng/L, and 896 ng/L, which represented an 9, 6, and 48-time increase compared with those obtained in 2017 (before COVID 19). The Azi removal efficiency had a different behavior compared to before COVID 19. The mean concentration of Azi in seawater and sediment samples was 9 ng/L and 6 ng/g, which was 3 and 4-fold higher than the previous study. Opposed to our former study, the Azi amount in the aqueous phase was less subjected to temporal seasonal variations. Our observations indicated the wide distribution of Azi in the environment and a future threat of intense growth of antibiotic resistance in ecosystems.


Subject(s)
COVID-19 Drug Treatment , Water Pollutants, Chemical , Water Purification , Anti-Bacterial Agents/analysis , Azithromycin , Ecosystem , Environmental Monitoring , Humans , Indian Ocean , Seawater , Wastewater/analysis , Water Pollutants, Chemical/analysis
2.
Environ Geochem Health ; 44(12): 4499-4521, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35129708

ABSTRACT

The current work is documented as the first record of the characteristics, removal efficiency, partitioning behavior, fate, and eco-toxicological effects of paraben congeners in a municipal wastewater treatment plant (WWTP, stabilization ponds) and hospital WWTPs (septic tank and activated sludge), as well as seawater-sediments collected from runoff estuarine stations (RES) and coastal stations (CS) of the north of the Persian Gulf. The median values of Σparabens at the raw wastewater and effluent of the studied WWTPs were 1884 ng/L and 468 ng/L, respectively. The activated sludge system had a greater removal efficiency (56.10%) in removing ∑parabens than the septic tank (45.05%) and stabilization pond (35.54%). The discharge rates of methyl paraben (MeP) was computed to be 2.23, 21.18, and 9.12 g/d/1000 people for stabilization ponds, septic tank, and activated sludge, respectively. Median concentrations of Σparabens in seawater (103.42 ng/L) and sediments (322.05 ng/g dw) from RES stations were significantly larger than from CS stations (61.2 and 262.0 ng/g dw in seawater and sediments, respectively) (P < 0.05). The median of field-based koc for Σparabens was 130.81 cm3/g in RES stations and 189.51 cm3/g in CS stations. It was observed that the concentration of parabens could have negative impacts on some living aquatic populations (invertebrates and bacteria), but the risk was not significant for fishes and algae.


Subject(s)
Environmental Pollutants , Water Pollutants, Chemical , Parabens/toxicity , Parabens/analysis , Sewage/analysis , Environmental Monitoring , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/analysis , Indian Ocean , Seawater , Wastewater/toxicity , Wastewater/analysis
3.
Membranes (Basel) ; 11(11)2021 Oct 25.
Article in English | MEDLINE | ID: mdl-34832042

ABSTRACT

This study describes the fabrication of sulfonated polyethersulfone (SPES) as a super-hydrophilic substrate for developing a composite forward osmosis (FO) membrane on a nonwoven backing fabric support. SPES was prepared through an indirect sulfonation procedure and then blended with PES at a certain ratio. Applying SPES as the substrate affected membrane properties, such as porosity, total thickness, morphology, and hydrophilicity. The PES-based FO membrane with a finger-like structure had lower performance in comparison with the SPES based FO membrane having a sponge-like structure. The finger-like morphology changed to a sponge-like morphology with the increase in the SPES concentration. The FO membrane based on a more hydrophilic substrate via sulfonation had a sponge morphology and showed better water flux results. Water flux of 26.1 L m-2 h-1 and specific reverse solute flux of 0.66 g L-1 were attained at a SPES blend ratio of 50 wt % when 3 M NaCl was used as the draw solution and DI water as feed solution under the FO mode. This work offers significant insights into understanding the factors affecting FO membrane performance, such as porosity and functionality.

4.
Ultrason Sonochem ; 68: 105187, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32485627

ABSTRACT

The waste sludge from shipping docks contains important elements that can be used as a catalyst after proper processing. The purpose of this study was to remove of amoxicillin (AMX) from the aquatic environment using waste sludge from shipping docks as catalyst in the presence of hydrogen peroxide/ultrasound waves. The catalyst was produced by treating waste sludge at 400 °C for 2 h. N2 adsorption, SEM, XRD, XRF, and FTIR techniques characterized the structural and physical properties of the catalyst. The BET-specific surface area of the catalyst reduced after AMX removal from 4.4 m2/g to 3.6 m2/g. To determine the optimal removal conditions, the parameters of the design of experiments were pH (5-9), contaminant concentration (5-100 mg/L), catalyst dosage (0.5-6 g/L), and concentration of hydrogen peroxide (10-100 mM). The maximum removal of AMX (98%) was obtained in the catalyst/hydrogen peroxide/ultrasound system at pH 5, catalyst dose of 4.5 g/L, H2O2 concentration of 50 mM, AMX concentration of 5 mg/L, and contact time of 60 min. The kinetics of removal of AMX from urine (k = 0.026 1/min), hospital wastewater (k = 0.021 1/min), and distilled water (k = 0.067 1/min) followed a first-order kinetic model (R2>0.91). The catalyst was reused up to 8 times and the AMX removal decreased to 45% in the last use. The byproducts and reaction pathway of AMX degradation were also investigated. The results clearly show that to achieve high pollutant removal rate the H2O2/ultrasound and catalyst/ultrasound synergy plays a key role.

5.
Environ Sci Pollut Res Int ; 27(7): 7463-7475, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31884533

ABSTRACT

The current investigation evaluates metal (loid)s biomonitoring using algae as well as the metal(loid) pollution of seawaters and sediments in the northern part along the Persian Gulf. Algae, seawater, and sediment samples were collected from four coastal areas with different land applications. The concentration of Ni, V, As, and Cd in abiotic samples (seawater and sediment) and four species of algae (Enteromorpha intestinalis, Rhizoclonium riparium, Cystoseira myrica, and Sargassum boveanum) was measured using an ICP-AES device. Concentrations of potentially toxic elements in seawater, sediments, and algae species followed the trend of "Ni˃V˃As˃Cd." The area of Asaloyeh (with the highest industrial activity) and the Dayyer area (with the lowest industrial activity) provided the highest and lowest amounts of metal(loid)s pollution, respectively. The average concentrations of V and As in four algae species significantly differed for all sampled areas. Obtaining the bio-concentration factor (BCF) > 1 for seawater and < 1 for sediment indicated that the studied algae have the ability to efficiently concentrate metal(loid)s from seawater and the limited accumulation of metals in sediments. According to the Nemerow pollution index, the order of metal(loid)s pollution for the studied areas estimated as Asaloyeh>Ganaveh>Bushehr>Dayyer. Algae species of C. myrica and E. intestinalis can often serve as suitable biological tools for monitoring seawater and sediment quality.


Subject(s)
Metals, Heavy , Phaeophyceae , Water Pollutants, Chemical , Geologic Sediments , Indian Ocean , Risk Assessment , Seawater
6.
MethodsX ; 6: 2217-2229, 2019.
Article in English | MEDLINE | ID: mdl-31667122

ABSTRACT

Heavy metal pollutants, particularly Pb are considered as critical contaminants causing harmful health risks for a human. In this study, montmorillonite modified with hexadecyl trimethyl ammonium chloride surfactant (N-HTAC) was applied as a new adsorbent for the Pb+2 adsorption from aqueous solutions. The N-HTAC was characterized by the scanning electron microscopy, x-ray diffraction, energy-dispersive x-ray spectroscopy, and Brunauer-Emmett-Teller. The central composite design using R software was chosen for modelling the effect of operating parameters. Based on the findings obtained from the analysis of variance, reduced full second-order model with multiple R2, 0.94, adjusted R2, 0.93, and LoF, 0.96, was represented satisfactory adjustment with experimental data. The Solver "add-ins" was employed to gain the optimum conditions for the modelling. The optimum operating points giving the maximum Pb+2 removal (99.99%), were found to be initial Pb+2 concentration: 0.1 mg L1- adsorbent dosage: 4.33 g L-1, HTAC dosage: 4.19 g L-1, pH: 7.13, temperature: 28.06ºC, and the reaction time: 103.4 min. The findings of the study showed that by enhancing and improving natural adsorbents, a significant amount of environmental pollutants can be eliminated. •In this study, a new modified adsorbent (N-HTAC) was used to remove lead ions.•The results of this study showed that the N-HTAC used has high efficiency (99.99%) in the removal of lead.•The results of this study and the data obtained can be used to supplement the information on the removal of contaminants with adsorbents.

7.
Data Brief ; 26: 104482, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31667247

ABSTRACT

This paper presents the performance of aquaporin forward osmosis membrane using chemical fertilizers as a draw solution. The comprehensive evaluation conducted for five conventional fertilizers ((CO (NH2)2, KCl, CaCl2, (NH4)2SO4) and (NH4)2HPO4) as draw solutions. The diluted fertilizer can be used directly for farming as fertigation. In this process, DSs do not need to be recovered and it is a single step desalination process. The data include the characterization of the intrinsic properties of the membrane samples and their performance under FO and PRO modes of operations. In addition, the data for various draw solution concentration under feed solution with deferent total dissolved solids (TDS) were evaluated. For example, a water flux of 17.5 L m- 2 h- 1 and 23.92 g m-2 h-1 reverse solute flux (RSF) was achieved under the FO operation mode for 3 M KCl.

8.
Environ Sci Pollut Res Int ; 26(29): 29748-29762, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31407259

ABSTRACT

The natural clay is an abundant, accessible, and low-cost material that has the potential for use in the water and wastewater industry. In this paper, Iranian natural clay and clay/Fe-Mn composite were used to remove toxic arsenic from the liquid environment. The natural clay and clay/Fe-Mn composite were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), energy-dispersive X-ray (EDX), X-ray diffractometry (XRD), thermo-gravimetric analysis (TGA), and atomic force microscopy (AFM) techniques. The effects of parameters (initial pH, temperature, sorption dose, and contact time) on the efficiency and behavior of the arsenic(V) adsorption process were studied. Freundlich (R2 = 0.945 and 0.989), Langmuir (R2 = 0.922 and 0.931), modified Langmuir (R2 = 0.921 and 0.929), and Dubinin-Radushkevich (R2 = 0.706 and 0.723) models were fitted to evaluate the equilibrium data of arsenic(V) adsorption process by natural clay and clay/Fe-Mn composite, respectively. The Langmuir adsorption capacity of arsenic(V) by the natural clay and clay/Fe-Mn composite was determined to be 86.86 mg/g and 120.70 mg/g, respectively. The arsenic(V) adsorption process followed the pseudo-second-order model. Negative values of ΔG° and ΔH° showed that the arsenic(V) sorption by the studied materials is thermodynamically spontaneous and exothermic. According to the findings, the natural clay and clay/Fe-Mn are suitable and recyclable sorbents for arsenic(V) adsorption from aqueous solutions. Also, the composite of clay with iron and manganese can improve the efficiency of clay in the removal of arsenic.


Subject(s)
Arsenates/analysis , Clay/chemistry , Iron/chemistry , Manganese/chemistry , Water Pollutants, Chemical/analysis , Water Purification/methods , Adsorption , Hydrogen-Ion Concentration , Iran , Kinetics , Models, Theoretical , Surface Properties , Thermodynamics , Wastewater/chemistry
9.
Environ Sci Pollut Res Int ; 26(7): 6336-6347, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30617884

ABSTRACT

In the current study, the bio-adsorption potential of Callinectes sapidus biomass for control of cadmium, nickel, and lead from the aqueous stream was assessed. Spectrum analysis of FTIR, AFM, EDAX, mapping, SEM, TEM, and XRF was used to study the properties of the C. sapidus biomass. The XRF analysis revealed that C. sapidus bio-adsorbent has various effective metal oxides that can be useful to adsorb pollutants. The best model to describe the equilibrium data was Freundlich isotherm. The Langmuir bio-adsorption capacity was reported at 31.44 mg g-1, 29.23 mg g-1, and 29.15 mg g-1 for lead, cadmium, and nickel ions, respectively. Pseudo-first-order and pseudo-second-order kinetic models were studied to test the kinetic behavior of the process. An intra-particle diffusion model was used to determine the effective mechanisms involved in the bio-adsorption. Based on t1/2, it can be concluded that the equilibrium speed of the bio-adsorption process is high. The thermodynamic study showed that the metal bio-adsorption process using C. sapidus biomass is exothermic and spontaneous. The field applicability of the crab bio-adsorbent for eliminating concurrently several contaminants (metal ions, antibiotics, sulfate, nitrate, and ammonium) from an actual wastewater was successfully examined.


Subject(s)
Brachyura , Cadmium/isolation & purification , Lead/isolation & purification , Nickel/isolation & purification , Wastewater/chemistry , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Adsorption , Animals , Biomass , Brachyura/chemistry , Kinetics , Oxides , Thermodynamics
10.
Data Brief ; 21: 364-370, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30364649

ABSTRACT

The data presented in this paper are produced as part of the original research article entitled "Thin-film composite membrane on a compacted woven backing fabric for pressure assisted osmosis" (Sahebi et al., 2017). This article describes how to fabricate a defect free membrane for forward osmosis (FO) and pressure assisted osmosis (PAO) on the woven mesh backing fabric support. Casting polymer on backing fabric support may limit the interfacial polyemirization due to wrinkled membrane surface. This paper presents data obtained from two different backing fabrics used as support for fabrication of thin film composite FO membrane. Backing fabric support were woven polyester mesh with different opening size. The data include the characterization of the intrinsic properties of the membrane samples, SEM and their performance under FO process. The structural parameters (S value) of the substrate were computed from thickness and porosity of the substrates. Thin film composite (TFC) membrane achieved a water flux of 8.1 L m2 h-1 in FO process and 37 L m2 h-1 using 0.5 M NaCl as draw solution (DS) and deionised (DI) water as the feed solution (FS) when applied hydraulic pressure was 10 bar.

11.
Sci Total Environ ; 627: 703-712, 2018 Jun 15.
Article in English | MEDLINE | ID: mdl-29426195

ABSTRACT

Occurrence and frequency of six most prescribed antibiotics (tetracycline, norfloxacin, azithromycin, anhydro erythromycin, cephalexin, and amoxicillin) were assessed in three wastewater treatment plants (WWTPs), and in water and sediments of the Persian Gulf at Bushehr coastline, Iran. The antibiotics concentration in the influent and effluent of septic tank (the hospital WWTP), activated sludge (the hospital WWTP), and stabilization pond (municipal WWTP) ranged between 7.89 and 149.63, 13.49-198.47, 6.55-16.37 ng/L, respectively. Conventional treatment resulted in incomplete removal of most of the studied antibiotics. Furthermore, the activated sludge was more effective in terms of antibiotic elimination compared to the stabilization pond or septic tank. The mean concentration of antibiotics ranged 1.21-51.50 ng/L in seawater and 1.40-25.32 ng/g in sediments during summer and winter. Norfloxacin was the dominant detected antibiotic in seawater, sediments, and influent of two hospital WWTPs. Seasonal comparisons showed significant differences for erythromycin and amoxicillin concentrations in seawater. Spatial variation indicated the role of physicochemical properties on distribution of antibiotics in seawater and sediments. The results emphasize the need to pay attention to antibiotic contamination in water and sediments of the Persian Gulf.


Subject(s)
Anti-Bacterial Agents/analysis , Environmental Monitoring , Seawater/chemistry , Water Pollutants, Chemical/analysis , Indian Ocean , Iran , Wastewater/chemistry , Wastewater/statistics & numerical data
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