Biodiesel production through transesterification of waste Pistacia- Terebinthus Oil by pharmaceutical waste as a heterogeneous catalyst: A sustainable solution for reducing external costs.

A catalyst from the pharmaceutical waste of calcium and magnesium tablets was synthesized for biodiesel production from waste Pistacia-Terebinthus (PT) oil with the aim of creating added value and presenting a new approach for the management of such wastes. For this purpose, magnesium and calcium tablet wastes with a mass ratio of 70:30 (wt%) were calcined. The catalyst was investigated by several methods, such as thermal gravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, Brunauer-Emmett-Teller analysis, X-ray photoelectron spectroscopy, and CHNS/O elemental analysis.

Mechanisms and controlling factors of heavy metals removal by electroflocculation in estuarine environments.

Estuaries play a crucial role in preventing the influx of metals from rivers into seas, thereby offering potential insights for the water purification industry. This study seeks to identify the key parameters (including pH, electricity conductivity (EC), and Eh) influencing the removal efficiency of Mn, Zn, Cu, Co, and Ni during natural and electro-flocculation processes in the Siahroud River estuary. The experiments were conducted in three stages, each representing varying salinity levels and voltage conditions, to determine the most effective parameters for metal removal.

Speciation characteristics, ecological risk assessment, and source apportionment of heavy metals in the surface sediments of the Gomishan wetland.

Metal contamination is one of the worldwide environmental issues. The main aim of this study was to evaluate the concentration, probable environmental risk, and source of investigated elements (Al, As, Co, Cr, Cu, Fe, Mn, Ni, and Zn) in sediments and water of the Gomishan wetland. Sediment contamination indices revealed sediments were solely polluted by As.

Development and application of novel risk indices for assessing heavy metal pollution in aquatic sediments.

This study presents the development of a new sediment individual risk index (SIRI) and sediment complex risk index (SCRI) to assess heavy metal pollution in Anzali Wetland sediments. SIRI incorporates total metal concentrations, bioavailability, and sediment quality guidelines. SCRI, derived through principal component analysis (PCA), integrates SIRI for a comprehensive risk assessment.

Investigating heavy metal pollution in Anzali coastal wetland sediments: A statistical approach to source identification.

In this study, the pollution and bioavailability of heavy metals in the sediments of Anzali Wetland were measured by analyzing data from sequential chemical extraction of sediments, risk assessment code (RAC), and sediment pollution indices. The average RAC results indicated that the risk from Zn, Cr, Cu, and Hg was low, while the risk from Pb, Ni, As, and Cd was moderate. To identify the sources of heavy metal pollution in the sediments of Anzali Wetland, multivariate statistical techniques such as Pearson correlation analysis, cluster analysis (CA), and principal component analysis (PCA) were employed.

Simultaneous dairy wastewater treatment and bioelectricity production in a new microbial fuel cell using photosynthetic Synechococcus.

Photosynthetic microbial fuel cell (PMFC) is a novel technology, which employs organic pollutants and organisms to produce electrons and biomass and capture CO by bio-reactions. In this study, a new PMFC was developed based on Synechococcus sp. as a biocathode, and dairy wastewater was used in the anode chamber.

Health risk assessment and source apportionment of potentially toxic metal(loid)s in windowsill dust of a rapidly growing urban settlement, Iran.

Rapid industrialization and urbanization have resulted in environmental pollution and unsustainable development of cities. The concentration of 12 potentially toxic metal(loid)s in windowsill dust samples (n = 50) were investigated from different functional areas of Qom city with the highest level of urbanization in Iran. Spatial analyses (ArcGIS 10.

Determining the appropriate mixing ratio in a multi-substrate anaerobic digestion of organic solid wastes employing Taguchi method.

The current research proposed a method for optimally combining feed input ratios in order to improve the quantity and quality of daily biogas production through optimizing the variable response level in the Taguchi method. The anaerobic digestion (AD) process of an existing plant in Iran was simulated through a set of two-stage pilot reactors under mesophilic temperature conditions in order to achieve optimal operational performance. Three common substrates (organic fraction of municipal solid wastes, fruit and vegetable wastes, and horse manure) along with two recirculated materials; the post-digestion sludge and the secondary digester slurry, were investigated in 16 experimental runs based on four different pre-surface hypotheses.

Integrated model for land-use transformation analysis based on multi-layer perception neural network and agent-based model.

The efficacy of land-use changes on aquatic ecosystems has been extensively studied in recent decades. Water resource management needs to understand the relationship between land-use change patterns and water quality, especially in urban areas. Hence, recognizing spatial-temporal changes in land use is required for sustainable development and proper water resource management.

Measurement and ecological risk assessment of heavy metals accumulated in sediment and water collected from Gomishan international wetland, Iran.

This study aimed to measure and ecologically assess heavy metals, including As, Cr, Pb, Cd, and Ni in water and sediment samples taken from Gomishan, an international wetland located in Golestan, Iran. Four sampling stations were selected to cover all parts of the wetland. The analyses of the heavy metals were performed by ICP-MS.

The thermodynamic stability, potential toxicity, and speciation of metals and metalloids in Tehran runoff, Iran.

Surface runoff is the most significant source of water in dry cities like Tehran. The surface runoff is polluted by heavy metals, which their risk level is a function of their speciation. Herein, Tehran runoff quality and the speciation of metals and metalloids were investigated.

Release of heavy metals under pre-set redox potentials in Musa estuary sediments, northwestern of Persian Gulf.

Sediments are capable of adsorbing and desorbing heavy metals (HMs) under various environmental conditions. This study investigated the impact of pre-set redox potential (Eh) on the release dynamics of HMs (Co, Cr, Cu, Ni, Pb, V, and Zn) from sediment in an automated biogeochemical microcosm. The release of Co, Pb, and V under reducing conditions increased that may increase the potential risks in the aquatic environment.

Impacts of land use and land cover change on the interactions among multiple soil-dependent ecosystem services (case study: Jiroft plain, Iran).

The spatial and temporal distribution pattern is an outstanding feature of the relationship among ecosystem services (ESs) that explains links between human activities and disturbed chemical composition of ecosystems. This study investigated the spatiotemporal variation of land use/cover changes (LUCC) and quantifies the change in four essential ecosystem services with an emphasis on soil (nutrient delivery ratio, carbon storage, crop production, and water yield) and their relationships in the Jiroft plain, Iran, during 1996-2016 through analytical tools including Land Change Modeler, and the Integrated Valuation of Ecosystem Services and Tradeoff. During the 20-year concentrate period, there was a considerable overall gain in cropland (5396 km) and urban (1787 km), loss of unused land (5692 km), water (2088 km), and forest (1083 km).

Exposure risk assessment, pollution level, and source identification of arsenic in soil: A case study of the Bardsir Plain (southeastern Iran).

In this study, we investigated the total arsenic concentration in the soil and the related human exposure risks in the central part of the Bardsir Plain in southeastern Iran. The results show that the average total arsenic concentration in agricultural soil is 50.26 mg/kg, which is 2.

Study of speciation and spatial variation of pollutants in Anzali Wetland (Iran) using linear regression, Kriging and multivariate analysis.

Multivariate statistical techniques and geostatistical methods are among the important tools used in surface water quality management. They are widely used in interpreting data, identifying the pollution sources, understanding the spatial variation of parameters, and determining the places of monitoring stations. Therefore, in this study, spatial variation of water quality and pollutants in the Anzali Wetland water (Iran) was evaluated using multivariate statistical and Kriging methods.

Contamination and cancer risk assessment of polycyclic aromatic hydrocarbons (PAHs) in urban dust from different land-uses in the most populated city of Iran.

Due to population growth and the considerable increase in usage of the resources, Human environment quality has been highly threatened by pollutants in recent decades. Polycyclic aromatic hydrocarbons (PAHs) are widespread, persistent organic pollutants which are of great concern due to their carcinogenicity. The present study is the first investigation that assesses contamination, sources and cancer risk of 16 priority PAHs proposed by US EPA in urban dust samples (n = 80) taken in different land-uses of Tehran metropolis, the capital of Iran.

A comparative study of elemental pollution and health risk assessment in urban dust of different land-uses in Tehran's urban area.

Pollution levels of potentially toxic metals (PTMs) were studied performing enrichment factor, geo-accumulation index and ecological risk index. The most enriched elements which categorize as very high and extremely high enriched in different land-uses were in order of: commercial Cu (73.79)>Hg (66.

The role of the estuarine zone on the river particulate toxicity.

Annually, a great volume of sediment and suspended particulate matters (SPMs) enters into the seas through estuaries. In the estuarine zone, metals present in SPMs may undergo conservative or non-conservative changes. In the present study, oxidation-reduction potential (ORP) as the most complex chemical parameter of open sea water and its relationship with the behavior of t metals in the estuarine area were investigated.

Temporal metal concentration in coastal sediment at the north region of Persian Gulf.

The purpose of this article is to study, result of metal concentration in two-sediment cores from Persian Gulf. Age of sediment is determined by C isotope method and bulk concentration is determined by ICP. This research output shows that, age of BandareAbbas core back to 9660 and Bushehr core to 15,600 years ago.

Removal of mercury from contaminated saline wasters using dithiocarbamate functionalized-magnetic nanocomposite.

In this study, an efficient adsorbent was proposed for the removal of mercury from saline water contaminated with mercury ions. FeO nanoparticles were modified using tetraethylenepentamine and carbon disulfide to incorporate dithiocarbamate functional group on the surface of the adsorbent. CHNS analysis confirmed successful modification of magnetic nanoparticles.

Fate of toxic metals during estuarine mixing of fresh water with saline water.

Metals are among the most common environmental pollutants, and their presence in high concentration in waters and biota have devastating effects on flora, fauna, and human health. Flocculation process of metals during estuarine mixing can reduce the environmental hazards of metals and also can provide micronutrients to the aquatic system. The present investigation provides a thorough study of eliminating colloidal elements of copper, manganese, nickel, lead, and zinc during estuarine mixing of Shalmanrood River water with Caspian Sea water in Iran.

Study on non-linear equilibrium, kinetics and thermodynamic of deltamethrin removal in aqueous solution using modified magnetic iron oxide nanoparticles.

The purpose of modification of magnetic iron oxide nanoparticles is an eco-friendly, emerging and economical method for removing deltamethrin in the aqueous solution and wastewater effluents when compared with other adsorbent methods. Modified magnetic iron oxide nanoparticles were synthesized by co-precipitation and then coupled with 3-hydroxytyraminium chloride. The nano-sorbent was characterized by thermogravimetric analysis, elemental analysis, transmission electron microscopy, scanning electron microscope, Fourier transform infrared spectroscopy, zero point charge and surface area determination.

Developing an environmental water quality monitoring program for Haraz River in Northern Iran.

Water quality management plans are an indispensable strategy for conservation and utilization of water resources in a sustainable manner. One common industrial use of water is aquaculture. The present study is an attempt to use statistical analyses in order to prepare an environmental water quality monitoring program for Haraz River, in Northern Iran.

The impact of increased oxygen conditions on heavy metal flocculation in the Sefidrud estuary.

Similar to natural filters, estuaries are capable of removing considerable amounts of heavy metal from rivers that flow into saline water environments by turning the metal into flocs. The research objective was to investigate the self-purification potential of estuaries in removal of metal by flocculation processes. Hence, flocculation of metal was studied experimentally in 5 aquaria with varying salinity levels.

Application of Multivariate Statistical Methods to Optimize Water Quality Monitoring Network with Emphasis on the Pollution Caused by Fish Farms.

Background: One of the key issues in determining the quality of water in rivers is to create a water quality control network with a suitable performance. The measured qualitative variables at stations should be representative of all the changes in water quality in water systems. Since the increase in water quality monitoring stations increases annual monitoring costs, recognition of the stations with higher importance as well as main parameters can be effective in future decisions to improve the existing monitoring network.