Noise and toluene are among the numerous physical and chemical pollutants that can induce adverse effects on different body tissues and systems; nevertheless, most studies have only experimented the auditory changes induced by co-exposure to them. The present in-vivo study aimed to examine the endocrine effects of co-exposure to toluene and noise on the testes and adrenal glands. In this experimental study, 24 healthy male New Zealand White rabbits were used. The noise intensity was 100 dB (white noise) and the toluene concentration was 1000 ppm for two consecutive weeks. The luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, cortisol and adrenocorticotropic hormone (ACTH) were measured using the enzyme-linked immunosorbent assay (ELISA) method. The hematoxylin and eosin stain method (H&E) was performed for the histopathological analysis. Comparing different parameters in different groups on post-exposure days was carried out using GEE (generalized estimating equations) method. The results indicated that noise and toluene increased cortisol, LH and FSH levels during different days after the exposure. Exposure to toluene and noise made vacuolization and reduction of primary spermatogonial cells in the testes. Moreover, lymphocyte infiltration, congestion, swelling and vacuolization were detected in adrenal glands through exposure to toluene and noise. Toluene and noise induced different destructive effects on the endocrine system. More studies are required to elucidate other endocrine changes induced by exposure to toluene and noise.

The main objective of the current study is to determine the distributions of the specific radioactivity concentrations (226Ra, 232Th and 40K) from terrestrial sources using gamma spectroscopy system (HPGe-detector). Forty (40) agricultural soil samples were collected from Wadi Al-Hussini and Tuban in Yemen. The study locations are famous for exporting coffee all over the world. The average of radio-concentrations of 226Ra, 232Th and 40K were 61.95±11.57, 32.33±8.03 and 1045.17±153.47 Bq/kg for Wadi Al-Hussini and 65.20±11.59, 50.95±9.80 and 1078.13±157.57 Bq/kg for Tuban, respectively. The obtained results are higher than the average worldwide values reported by UNSCEAR. So, it is not acceptable with global safe criteria. Also, the radiation hazard parameters such as radium equivalent activity, absorbed gamma dose rate, outdoor and indoor annual effective dose equivalent, external and internal radiation hazard index, gamma index level, annual gonadal dose equivalent and excess lifetime cancer risk. All of these parameters are acceptable and within the worldwide values. The obtained results could be considered as reference data to follow up any changes in the future for natural radionuclides pollutants and their risks in the study area.

This study presents a new approach to solve the one-dimensional solute transport equation with variable coefficients and two input sources in a finite porous media. The medium is divided into m-layers porous media with constant averages coefficients in each transport problem. The transport equations in layer i-1 and i are coupled by imposing the continuity of solute concentration and the dispersive flux at the interfaces of the layers. Unknown functions representing the dispersive flux at the interfaces between adjacent layers are introduced allowing the multilayer problem to be solved separately on each layer in the Laplace domain before being numerical inverted back to the time domain. The obtained solution was compared with the Generalized Integral Transform Technique (GITT) and numerical solutions for some problems of solute transport with variables coefficients in porous medium present in the literature. The results show a good agreement between both solutions for each of the studied problem. An example of application considering an advective-dispersive transport problem with a sinusoidal time-dependent emitting rate at the boundary was study in order to illustrate the effect of sinusoidal frequency on solute concentration.

Nowadays, the pollution of sulfur compounds is gradually increasing due to the growing wastewaters and industrial developments. In this study, 2-mercaptobenzothiazole (MBT) removal from aqueous solution has been investigated using the combination of the ultrasonic and UV waves (ultra/UV). The effective parameters include pH, irradiation time, initial concentration of MBT, and volume of hydrogen peroxide at constant temperature of 25 °C. To exact evaluation of the design of experiments (DOE) and analyze of variance (ANOVA), response surface methodology (RSM) was employed. The results revealed that waves’ energy and subsequently cavitation phenomenon and hydroxyl radicals played significant roles in cracking the studied organosulfur’ bonds. In addition, hydrogen peroxide oxidant promoted the sulfur removal in the process. Maximum sulfur removal was numerically optimized as 99.74 that had an absolute error of 1.47% in comparison with the experimental one (98.29). Finally, COD and DO analyses were studied at optimum conditions. The tests confirmed the experimental results, appropriately. Therefore, the combination of the ultrasonic and UV irradiation can be significantly effective on removing organosulfur’s pollutants in industrial wastewaters and related ones.

Heavy metals contamination of rainwater is a function of the adsorbed metals present in the particulates of the atmosphere in which the rain was formed from and rainwater chemistry is an alternative way of monitoring urban air pollution for predominant metal species. Three distinct sampling sites (residential, industrial and commercial) were investigated in the south western part of Nigeria for one year. After acid digestion, quantification was done using a double-beam Atomic Absorption Spectrophotometer (AAS). The obtained results showed that heavy metals were predominantly present as free metal ion in the commercial and industrial areas but Mn and As mainly occurred in the suspended fraction. Residential area presented major fractions as bound to organic complexes except Cu and Cd which were principally available as suspended fraction. The health risks associated with the intake of the studied rainwaters indicated susceptibility to possible carcinogens upon consumption due to total RI > 10-4. Ecological risk assessment equally shown a very high level of ecological risks related with the metals due to RI ˃ 600. Sequel upon this, there is need for better sensitization of the citizenry to the sources and control of these pollutants.

This study was conducted to assess air quality status in the selected cities of Pakistan through Air Quality Index (AQI) and Multi Pollutant Index (MPI) and their correlation. Secondary data on air pollutants’ concentrations for the year 2021 were used from the literature. For this investigation, major air pollutants including carbon monoxide, nitrogen dioxide, sulfur dioxide, and particulate matter were used and compared with Punjab Environmental Quality Standards. Air quality indices, Multi Pollutant Index (MPI) and the Air Quality Index (AQI) were used in the study. Overall condition of the air pollutants in the particular location was described using the Air Quality Index. For this formula, the average concentration of each pollutant across a range of time periods was first calculated. The concentration of each pollutant was then divided by the relevant standard value, which was then cumulatively averaged and represented as a percentage. Results showed that Lahore and Karachi are two of the cities with unhealthy to hazardous AQI values and poor air quality according to MPI values. Air quality is deteriorating in industrial and traffic-congested cities where pollution levels significantly exceeded the threshold values. Using the linear regression, the results confirmed the strong association between the AQI and MPI. There is a need for immediate action to be taken to lower pollutants’ concentrations and improve air quality in urban areas.

Two fly ashes from municipal solid waste incineration were selected to study their heavy metal leaching behavior. The main purpose of this research is to investigate the characteristics of fly ashes and compare the leaching of heavy metals in different leaching environment. pH and acid neutralization capacity analysis showed that fly ashes were highly alkaline. Fly ashes also contained a variety of heavy metals including Pb, Cu, Cr, Zn, Cd and Ni etc. Leaching studies showed that the alkalinity of fly ashes raised the pH of leaching solution from acidic to basic. Ni, Cu and Zn were strongly bound to ashes and manifested low leaching. In contrast, Cr and Cd had high mobility but their leaching was inhibited by the low solubility of carbonate Cr and Cd. Pb was highly leachable in the alkaline environment with concentration in the leaching solution reached as high as 9.74 mg/L. In addition, the presence of EDTA in the environment also increased leaching. Pb concentration was raised to 16.63 mg/L. This could be attributed to the chelating capacity of EDTA which means that the presence of organics in natural environment should be taken into consideration.

Natural quartz mineral was examined as a new sorbent for Hg(II) removal from synthetic wastewater systems. Batch adsorption experiments of Hg(II)  onto quartz mineral were conducted under various conditions such as solution pH, sorbent dosage, contact time, initial Hg(II)  concentration. Adsorption experiments results of Hg(II) by quartz mineral showed good achievement after 180 min with 1.0 g/L sorbent mass at pH of 2.0, agitation speed of 200 rpm and a temperature of 25°C. Moreover, the Hg(II) concentration was directly related to increases the adsorption capacity, the maximum Hg(II) uptake by quartz  sample was 16.52 mg/g for 80 mg/L (C0 (Hg(II)].  Langmuir isotherm and pseudo-second-order kinetics (R2 > 0.99) were found to be the most appropriate models to describe the adsorption of Hg(II) by quartz mineral. The intra-particle diffusion model and the calculated Dubinin–Radushkevich adsorption energy (Eads = 0.78 kJmol-1), confirms a physisorption adsorption reaction occurring in three stages.

Boreal freshwater ecosystems are highly sensitive to pollution, but too little information is available on the use of both biotic and chemical indicators for estimation of the effect of wastewater on boreal rivers and streams. The purpose of this study was to assess the wastewater impact on the boreal river (Perm Krai, Russia).  Physicochemical parameters of major ions and trace elements were detected with a field portable unit, capillary electrophoresis, and ICP-MS. Fish data was collected by gillnets. To evaluate the level of pollution from the Tolych River upstream to downstream, we calculated heavy metal evaluation index (HEI), ecological risk index (ERI), and index of biotic integrity (IBI). The anthropogenic impact from upstream to downstream showed the range from a very high to medium level of pollution by ERI and from a high to medium level by HEI values, where most of the studied major ions and trace elements often exceeded aquatic life limits. We found significant thermal pollution of the observed river with the decreasing temperature gradient from pollution source down to the river mouth due to hydromorphological factors. Observed thermal pollution leads to the absence of thermally sensitive cold-water fish species and the abundance of ecologically flexible fish species. The water quality assessed by biotic IBI index showed low and very low quality of lower reach of the studied river, which contradicts the results of assessment by HEI and ERI indices.  The results show the importance of using aquatic organisms as bioindicators for assessing ecological water quality.

Laboratory wastewater is categorized as hazardous waste that should not be released into the environment since it poses a serious threat to environmental safety. In the present study, the use of Sulphate-Reducing Bacteria (SRB) colonies in an anaerobic reactor to treat heavy metals-containing laboratory wastewater was examined. SRB was initially cultivated with the treatment of fermented compost and Postgate's medium before being attached to the laboratory-size anaerobic reactor to treat laboratory waste containing heavy metal. Within the 15 days of initial incubation under the room temperature of 28 °C, we discovered that SRB optimally grew on the medium with the composition of 5% Postgate B solution, 30% fermented compost liquid, and 5% active suspension liquid, with a total population of cell colonies was 1.2 x 105 CFU/ml. After SRB colonies from the most optimum medium were affixed to the reactor, the reactor attained 89% of lead (Pb) removal, 69.78% of iron (Fe) removal, and 48.93% of copper (Cu) removal for 15 days treatment periods. On the 21st days of treatment time, the removal efficiency increased significantly to 91.57%, 78.09%, and 83.56% of Pb, Fe, and Cu removed, respectively.