A study on natural radioactivity in virgin and agricultural soil samples collected from Sungai Petani was conducted using high-purity germanium. The mean activity concentrations of 226Ra, 232Th, and 40K in virgin soils were 51.06±5.83, 78.44±6.42, and 125.66±7.26 Bq kg−1, respectively, while those in agricultural soils were 80.63±5.78, 116.87±7.87, and 200.66±18.24 Bq kg−1, respectively. The corresponding activity concentrations in agricultural soils were higher than those in virgin soils and those reported for other countries of the world. The average values of radium equivalent activity (Raeq), external hazard index (Hex), internal hazard index (Hin), outdoor annual effective doses (Eout), and indoor annual effective doses (Ein) in agricultural soils were 258.38 Ba kg−1, 0.708, 0.925, 0.162 mSv y−1, and 0.669 mSv y−1, respectively. The average values of outdoor external dose (Dout) and indoor absorbed dose (Din) rate in agricultural soils were 116.04 and 218.46 nGy h−1, respectively, which were higher than the permissible limit. Soil with Hex and Hin less than unity are suitable for use as building materials and in agriculture.

In this research, gasoline vapours including Benzene, Toluene, Xylene (BTX) and Total Volatile Organic Compounds (TVOCs) emitted from vent pipes of underground storage tanks (USTs) were measured at six gas stations in Tehran. Thereafter, gas station No. 29 was selected as a pilot station and equipped with a vapour control system. The vapours were measured during the summer of 2013 and winter of 2014 in two states, before and at the time of gasoline discharge from a petrol tanker to the UST. The results reveal that the average of BTX and TVOCs are 161.22, 200.81, 229 and 647.01 ppm, respectively, higher than the World Health Organisation (WHO) guidelines. The average of TVOCs and BTX in the situation in which the control system is inactive at the pilot station, are 259.13, 55.9, 73.03 and 96.88 ppm, respectively. After activating the control system at the pilot station, the VOCs were reduced by 0.01 ppm. Almost 99.99% control was obtained for this system and 87% of the people living around the pilot station were satisfied and no longer had any complaints about the bad odour of VOCs. It can be concluded that gasoline discharge from the petrol tanker to UST, is the main reason behind the overproduction of VOCs in Tehran's gas stations (P<0.001). So, the most important element is to reduce VOCs at Tehran's gas stations by installing a vapour control systems in all the stations and activating the systems at the time of gasoline discharge.

Duckweeds are of special interest, as they are naturally growing weeds that have the capacity to tolerate and remove toxic pollutants, including heavy metals from the environment. Studies have revealed that duckweed (Lemna minor) can tolerate and remove heavy metals from aqueous solutions. In the present study, the efficiency of L. minor in the removal of Ni and Cr individually from aqueous solutions was investigated at concentrations of 3.05, 3.98 and 4.9 mg/L for Ni and 1.91, 2.98, and 4.2 mg/L for Cr. Experiments were run for 22 days, after which the metal content in the plant was estimated by atomic absorption spectrophotometer (AAS). The duckweed showed higher percentage of Ni removal than Cr. Specific Growth Rate (SGR) was found to be reduced at high concentrations of both Ni and Cr. Statistical analysis suggested that the growth of the plant was affected by the toxic effect of both Ni and Cr. Bioaccumulation of Ni was higher than Cr in L. minor. The mechanism of removal of both Ni and Cr followed second order kinetics. It is suggested that these duckweeds can remove Ni and Cr from aqueous solution and can also accumulate the same in considerable concentrations, at low initial metal concentrations.

Haraz-Ghareh Su is one of the seven sub-basins of the Caspian basin, located on the southern shores of the Caspian Sea, and as such, is in danger of water crisis due to absence of proper systematic policy and strategy. In this study, the pressure factors on the Haraz-Ghareh Su water resources were identified using DPSIR model. Then, the pressure parameters on the freshwater resources in the Caspian Basin were scored and prioritized into two categories: human and non-human criteria and eight sub-criteria with the help of questionnaires (the opinion of 36 specialists in environmental planning and management, as well as the use of FANP). Thereafter, the data layers were processed with the help of IDRISI software, and eventually, the data were overlaid in the ArcGIS and the final plan was made. The findings of the study shows that, among 8 effective sub-criteria on the environmental planning and management of the freshwater resources in the Haraz-Ghareh Su Basin, agricultural water consumption with 0.243 score points and dam-making with 0.039 score points are considered most and least important sub-criteria, respectively. Consequently, after the compilation and scoring of sub-basins of the Caspian basin, it appears that the sub-basin of Haraz-ghare Su with 0.158627 points had the worst situation in terms of the planning and management of freshwater resources in the Caspian basin. In order to decrease the pressure on the freshwater resources in the Haraz-Ghareh Su Basin, the formulation of long-term policy and strategy in this basin seems to be essential.

Today, the cement industry is one of the major air polluting industries in the world. Hence, in this study, owing to the importance and role of contaminants from the plant, an appraisal of the emission contributions in addition to other factors have been discussed. There are several reasons behind the importance of modeling air pollutants. First, the assessment of standards for air pollution, and the fact that the measurement points are limited. Furthermore, in all industrial areas, measurement and installation of assessment and monitoring stations are not feasible. The AERMOD model is a dispersion steady state model which is utilized to determine the concentration of various pollutants in different areas from urban and rural, flat and rough, shallow diffusion in height, from standpoint and different shallow sources. In this model, it is assumed that the dispersion of concentration in Stable Boundary Layer (SBL) in two horizontal and vertical directions are similar to that of horizontal within Gaussian convectional boundary layer (CBL). With regard to assessment of the parameters and pollutants of stack outlet, the amount of particulate matter was measured as the most important pollutant in the region. Then, via dispersion and diffusion modeling of pollution (AERMOD) along with environmental measurements, the nature of dispersion of this pollutant in the analysis of the surrounding areas was verified. According to the presented results, the highest level of concentration for particulate matters in all areas affected by cement factory amounts to 43.68 (μg/m3) which occurred at a distance of 1500 m in the east direction and 2100 m in the north direction.

The aim of the present study was to evaluate Vitamin C (VC) as a potent natural antioxidant to mitigate the genotoxic effects of Arsenic trioxide and sodium fluoride in Swiss albino mice in vivo. The study was divided into eight groups consisting of control treated with normal saline (Group I), Group II, III, IV, V, VI, VII and the VC group with only Vitamin C (500 mg/kgbw). Arsenic trioxide (4 mg/kgbw) and Sodium fluoride (8 mg/kgbw) were administered singly, as well as in combination to swiss albino mice, with and without VC. In this study, the genotoxic effect of arsenic (As) and fluoride (F) in mice using comet, chromosomal aberration and lipid peroxidation assay was investigated. The results revealed that VC efficiently ameliorates the genotoxic effect of As and F by increasing the frequency of chromosomal aberrations and primary DNA damage along with increased malondialdehyde (MDA) level. In conclusion, VC mitigates the genotoxic effects of the two well-known water contaminants (As and F) effectively and efficiently at the given concentration in vivo.

The application of the electro-coagulation process to the identified contaminated groundwater at Abala community, a suburb of Ilorin metropolis in Kwara state, Nigeria, is the subject of this study. The groundwater samples were electro-coagulated in a batch reactor of 2.5L containing 1 litre volume of contaminated groundwater for 1 hour per run using a DC power supply ranging from 10v to 20v at constant current 5amp and 2amp to 6amp at constant voltage 10v using graphite electrodes. The results revealed that electro-coagulation process can reduce turbidity, TDS, Electrical Conductivity, BOD, TOC, COD, and color by 97.3 %, 91.2 %, 91.1 %, 96 %, 99.7%, 99.7%, 79.9%, and 82.96 %, respectively. Through Atomic Absorption spectroscopy analytical study, the process also shows removal efficiency of Manganese, Iron, and Zinc of 82.96 percent, 70.0 percent, and 95.30 percent, respectively. The outcome of the electro-coagulation process met the World Health Organization (WHO), the United States Environmental Protection Agency (USEPA), and the Water Environment Partnership In Asia (WEPA) criteria for both drinking water and general industrial wastewater discharge guidelines. The electro-coagulation treatment for contaminated groundwater was efficient and effective, therefore it is recommended in this study for Nigerians.

The aim of this study was to determine by SEM-EDS analysis of the surface morphologies of the periostracum and nacreous layer and to determine the sodium (Na), Strontium (Sr), manganese (Mn), potassium (K), titanium (Ti), iron (Fe), magnesium (Mg), cobalt (Co), copper (Cu), chromium (Cr), zinc (Zn) and nickel (Ni) metals levels in the shells of the mussel (Potomida semirugata, Unio terminalis, Anodonta pseudodopsis and Leguminaia wheatleyi) obtained from Gölbaşı Lake, Turkey. The results of the study, the representative SEM analysis and corresponding EDS spectra of the periostracum and nacreous layer of the shells of freshwater mussels confirmed the presence of elemental compositions, including CaCO3. P. semirugata and U. terminalis have the aragonite prismatic layer that shows typical polygonal organizing, regular and polygonal crystal forms, with hexagonal and coexisting rhombic shapes. However, while A. pseudodopsis has round aragonite crystals (Rc), L. wheatleyi has irregular crystal plate layers (Irc). CaCO3, detected strong Ca peaks as well as C and O peaks with Mg and Si peaks. On the other hand, sodium (Na) was found in the highest concentrations ranging from 82.30±0.040 to 155.37±0.050 μg/g, and its concentrations were also higher than those of other metals in all species. The most abundant elements in shells of four freshwater mussel’s species were Sr, Na, and Mn which ranged from 26.07±0.44-58.023±0.52 μg/g, 82.30±0.040-155.37±0.050 μg/g, and 6.06±0.044-9.66±0.053 μg/g respectively. To our knowledge, this is the first study in Turkey that is researched the different four freshwater mussel species in the Gölbaşı Lake, Turkey.

Water and sediments have become a major threat. Heavy metals, some of which are potentially toxic, are distributed in different areas by different routes. Tafna river was studied upstream and downstream under contrasting hydrological conditions during the year 2020.The different levels and sources of pollution are assessed by combining geochemical indicators: geoaccumulation index (GI-go), contamination factor (CF), pollutant loading index (PLI) and supplemented by correlation matrix (CM) as statiscal analyses added principal component analysis (PCA). The elements analysed were physical and chemical parameters (pH, DO, electrical conductivity CE and, COD BOD5), and the metallic elements (Fe, Cd, Pb, Cu, Mn and Zn). They were classified based on how contaminated they were: for the water compartment (Fe> Mn>Cu>Pb>Cd>Zn), while for sediments (Zn> Pb>Fe>Cd>Cu >Mn). The results suggest that the chemical composition of the waters of the Tafna river is influenced by the lithology, which contributes to the enrichment of the sediments. All of the indicators suggest an average levels of sediment and water pollution at the Tafna's summit, then decreases towards the bottom due to the geomorphology with multiple sources of pollution. As a result, our study offers the first comprehensive information on the amount of heavy metals present in the riverbed's sediment and water.

Conventional remediation techniques have become outdated and insufficient to treat the influx of pollution from different fronts (air, water, and soil). Green synthesis of nanoparticles is an eco-friendly approach to remediate these contaminants and Membrane technology is increasingly becoming popular for the treatment of wastewater due to their efficiency and versatility against a wide array of contaminants. Cellulose acetate (CA) is a polymer obtained from cellulose and hence considered biodegradable, making it a more environmentally friendly option over other conventional polymers. In this present study, silver nanoparticles were synthesized using Staphylococcus aureus and characterized by UV-vis Spectrometer, Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Analysis (EDAX). The synthesized green silver nanoparticles were assimilated onto synthesized CA membrane films to fabricate nanocomposite membranes (CA-X, CA-X1 and CA-X2). EDAX results showed higher counts of silver at 3keV on the CA-X, confirming that silver nanoparticles were properly embedded on the membrane. Physio-chemical tests performed on the collected sewage, showed that the total dissolved solids (TDS) were found to decrease significantly during the first hour of treatment, CA-X1 showed 16.2% decrease and 21.95% decrease was observed by CA-X2. A decrease in total nitrogen content by 38.88% and 41.36% for CA-X1 and CA-X2 respectively was recorded after a week’s treatment. Therefore, the work displayed the capability of cellulose acetate nanocomposite membrane for leachate treatment, since it displayed its potential in remediating leachate in a short span of time and scalability could be achieved for a larger volume of leachate with larger nanocomposite membranes.