Bushehr University of Medical Sciences
Bushehr University of Medical Sciences RepositoryNot a member yet
7809 research outputs found
Sort by
BTEX compounds leachates from cigarette butts into water environment: A primary study
No full textBTEX compounds can easily leach from cigarette butts into water and time after smoking has a significant effect on BTEX levels in leachates. © 2020 Elsevier Ltd
Cigarette butts (CBs) are the most abundant types of litter in the environment and may contain toxic chemicals such as BTEX that pose serious risks to the water bodies and health of aquatic organisms. So far there is no systematic study on BTEX compounds (benzene, toluene, ethylbenzene, o-xylene, and p-xylene) leaching from CBs into water environments. In this work, the leaching concentrations of BTEX compounds in deionized water (DW) and river water (RW) samples were studied for the first time. The mean concentrations of benzene, toluene, ethylbenzene, p-xylene, and o-xylene at contact times of 15 min to 1 day in water samples ranged from 0.13 to 0.18, 0.39–0.9, 0.11–0.25, 0.12–0.38, and 0.09–0.19 μgL−1 respectively. Benzene, toluene, ethylbenzene, o-xylene and p-xylene were detected at all contact times in both DW and RW samples. There were no significant differences of the leachate levels of BTEX compounds between DW and RW samples. The highest and lowest mean concentration levels in both DW and RW samples were determined for toluene and o-xylene respectively. The time after smoking had a significant effect on BTEX levels in leachates. The concentration levels of benzene, toluene, ethylbenzene, o-xylene and p-xylene leachates in water samples, after only 15 min, were reduced by 100, 93, 70, 68, and 59 percent respectively. Our data revealed that leached concentrations of benzene did not exceed the Water Framework Directive (WFD) guidelines, but with regard to the amount of CBs littered each year and other toxic chemicals contents of CBs this can still be a threat for aquatic creatures and possibly humans as well. Further studies are needed to cover the knowledge gap on the toxic leachates from CBs into water systems
Appropriate fixative for MEM-G/9 staining of cultured human HLA-G-positive JEG-3 trophoblast tumor cells
No full textHuman leukocyte antigen (HLA-G) participates in immunosuppression and is useful for prenatal diagnostics. Isolation of fetal cells positive for HLA-G by HLA-G antibody conjugated nanoparticles from the cervix of pregnant women is the basis for non-invasive prenatal testing. Endocervical specimens are fixed in transport medium before isolation using antibody conjugated nanoparticles. Staining of HLA-G using MEM-G/9 antibody, however, is restricted to unfixed cells. We investigated the effect of several fixatives on the interaction of HLA-G with MEM-G/9 in the HLA-G-positive cell line, JEG-3. We investigated absolute methanol, 1:1 acetate buffer:methanol, Pap solution and paraformaldehyde. The effects of these fixatives were evaluated using immunofluorescence. We found no MEM-G/9 surface staining of methanol fixed cells. Approximately 40% of JEG-3 cells fixed with paraformaldehyde failed to stain. Nearly all cells were stained with MEM-G/9 following fixation with acetate buffer:methanol or Pap solution. Our findings indicate the importance of using an appropriate fixative for preserving HLA-G cell surface antigen for studies using the MEM-G/9 antibody
Potentially toxic elements leachates from cigarette butts into different types of water: A threat for aquatic environments and ecosystems?
No full textTrillions of cigarette butts (CBs) are released into the environment and the leached potentially toxic elements (PTEs) from CBs may contaminate the environments. In this study, the leaching of PTEs including both heavy metals and metalloids (metal(loid)s) from CBs into deionized water (DW), tap water (TW), and seawater (SW) was checked during the different contact times (from 60 min to 60 days). According to the results, PTEs were leached from CBs into different water samples. However, there were no significant differences between leachates in DW and TW samples (p > 0.05). The results of the distribution coefficient indicated the high tendency of most PTEs to enter the liquid phase. The levels of leached PTEs into DW and TW exceeded the standards of surface freshwater to maintain aquatic life. Although the maximum level of leached metal(loid)s into DW, TW, and SW occurred at different times, for each type of water sample no significant differences were found among the levels of most PTEs at various contact times. Based on the results, the levels of leached metal(loid)s from CBs in seawater peak soon after being released into the water, while for the freshwater, they occur after some days. This phenomenon could possibly have short-term and long-term effects on marine and freshwater organisms, respectively. Due to the ability of the dissolved PTEs to integrate into the aquatic/terrestrial food web and threaten human health, some control measures regarding the disposal of CBs are necessar
Fluoride content and hazard quotient for beverages marketed in iran
No full textBeverages are one of the main sources of fluoride (F) entry to the body, especially in some countries located in the tropical regions. The aim of this study was to determine, for various beverages available in markets in Iran, the F concentration, the estimated daily intake, and the hazard quotient value (HQ), a measure of non-carcinogenic risk. The beverages studied were: doogh (a popular dairy-based drink in the Middle East produced from fermented milk made from mixing yoghurt, water, herbs, and salt), carbonated soft drinks, non-alcoholic beers, and energy drinks. The F contents of 105 beverage samples were analyzed by using an ion-selective electrode. The range and mean values (mg L-1) of the F concentrations found in the various beverages were: doogh: 0.058–0.86, 0.21; carbonated soft drinks: 0.012–1.10, 0.23; non-alcoholic beers: 0.006–0.58, 0.11; and energy drinks: 0.076–1.60, 0.37. The results indicated that there was a statistically significant difference between the F levels of the energy drinks and the other beverages. The HQ values for all the age groups showed that no significant risk of fluoride toxicity for consumers was present due to beverage consumption. However, it should be noted that other F sources such as drinking water, food, toothpaste and other beverages, such as different types of tea, may contribute to a higher intake of F in body and consequently, increase the risk of adverse health effects from high F exposure
Predicting physical and verbal aggression perpetration among teenage boys: an application of the theory of planned behavior
No full textPurpose: Aggression has been introduced as one of the serious problems in public health. The purpose of this paper is to evaluate the ability of the extended theory of planned behavior (TPB) to predict the physical and verbal aggression behavior. Design/methodology/approach: In this research, 462 teenagers were evaluated through the demographic questionnaire along with the main structures of the TPB as a predictor of behavior. After one month of follow-up, physical and verbal aggression was evaluated. Demographic data were analyzed descriptively by SPSS21 and predictability of the structures for intention and behavior of the physical and verbal aggression was analyzed by AMOS. Findings: Mean and standard deviation of participants’ age were 14.70 and 1.12 years, respectively. In this research, 22.5% of the participants did not show physical aggression over the last one month and 20% of them did not show verbal aggression over the last month. Path analysis revealed that the variables of the TPB predicted 61% and 32% of variance of intention and physical aggression behavior, respectively, while these variables could describe 43% and 22% of the variance of intention and verbal aggression behavior, respectively. All of the concepts could be significant predictors of the behaviors. Subjective norms were the best predictor of the intention for physical and verbal aggression. Intention and perceived behavioral control were good predictors of physical and verbal aggression. Research limitations/implications: Given the role of subjective norms in intention and also the role of intention and perceived behavioral control of people for aggression, it can be concluded that emphasis on social and psychological education about subjective norms, peer groups and self-control can help reduce this problem. Originality/value: A few studies have predicted behavior occurrence in the future. Given the lack of focus on the role of constructs that may bring about future behaviors, the current research was conducted to use the structures of the TPB to predict behavioral intention as well as perpetration of physical and verbal aggressive behaviors, independentl
Decoration of Citrus limon wood carbon with Fe3O4 to enhanced Cd2+ removal: A reclaimable and magnetic nanocomposite
No full textIn the present study, the activated carbon of lemon (ACL) was generated from Citrus limon wood waste and composited with Fe3O4 nanoparticles. The ACL/Fe3O4 magnetic composite was effectively used to eliminate Cd2+ from an aqueous solution. The active surface area values for ACL and ACL/Fe3O4 magnetic composite were 25.99 m2/g and 38.70 m2/g, respectively indicating the effectiveness of Fe3O4 nanoparticles in improving ACL active surface area. The response surface methodology with central composite design (RSM-CCD) was used to determine optimal values of pH, ACL/Fe3O4 dose, contact time, and Cd2+ concentration on the decontamination efficiency. The Langmuir and Freundlich isotherm models had more potential to describe the adsorption process using ACL and ACL/Fe3O4, respectively. The Langmuir-based adsorption capacity was obtained as 28.2 mg/g (ACL) and 39.6 mg/g (ACL/Fe3O4). A pseudo-second order (PSO) model was successfully applied to evaluate the adsorption process kinetic behavior. A higher value of α parameter for ACL/Fe3O4 (5.7 mg/g.min) than that of ACL (3.5 mg/g.min) indicated that the magnetic composite had a greater tendency to absorb Cd2+. In addition, the Weber–Morris model showed that various mechanisms such as intraparticle diffusion and boundary layer effects may have a role in the adsorption process. The study of ad(de)sorption behavior showed that the adsorbents have a good ability to adsorb Cd2+ and no significant change in their performance has been made up to 4 times of reuse. Our results showed that ACL modification using Fe3O4 nanoparticles improved the adsorption efficiency of ACL to remove Cd2+ from the aqueous solutions. © 2021 Elsevier Lt
Use of toenail-bounded heavy metals to characterize occupational exposure and oxidative stress in workers of waterpipe/cigarette cafés
No full textTobacco smoke is known for releasing metals in indoor air of waterpipe/cigarette cafés. However, the worker exposure to metals, and its association with oxidative stress in these cafés are still unclear. To this end, 54 workers and 38 customers from waterpipe/cigarette cafés (the exposed group), 30 workers from non-smoking cafés (the control group 1 (CG_1)) and 32 individuals from the general population (the control group 2 (CG_2)) were selected and toenails samples were then taken from them. Our findings revealed a significant difference in terms of toenail-bounded metal levels between the exposure and control groups (CG_1 and CG_2) (Mann–Whitney U test, Pvalue < 0.05). This study has also indicated that "type of tobacco" could be considered as a predictor for toenail-bounded heavy metals. Furthermore, our research’s results suggest that toenail-bounded heavy metals are positively and significantly correlated with urinary levels of 8- hydroxy-2′-deoxyguanosine (8-OHdG, as a biomarker for the degradation of deoxyribonucleic acid (DNA) oxidative stress). Therefore, it can be concluded that workers of waterpipe/cigarette cafés are at high risks of adverse health of DNA oxidative degradation
Emerging endocrine disruptors in two edible fish from the Persian Gulf: Occurrence, congener profile, and human health risk assessment
No full textThe occurrence of endocrine disrupting chemicals (EDCs) has been determined in two widely consumed fish species from Persian Gulf i.e., Epinephelus coioides and Platycephalus indicus by applying a validated analytical for the simultaneous detection of fourteen EDCs. The concentrations of all detected EDCs were greater in the liver than in the muscle (except for bisphenol A in P. indicus), suggesting a prolonged exposure of the fishes to these pollutants in the Persian Gulf. Specifically, the results showed that di (2-ethylhexyl) phthalate (DEHP) was the compound detected most frequently and at the highest concentration in both species. DEHP levels in ranged from 6.68 to 297.48 μg g-dw−1 and from 13.32 to 350.52 μg g-dw−1, in muscle and in liver, respectively. A risk assessment study was conducted, and demonstrated that consuming two fish based- meals per week may result in a moderate risk especially for vulnerable population groups
Occurrence, spatial distribution, seasonal variations, potential sources, and inhalation-based health risk assessment of organic/inorganic pollutants in ambient air of Tehran
No full textThe present study evaluated the concentrations, spatial distribution, seasonal variations, potential sources, and risk assessment of organic/inorganic pollutants in ambient air of Tehran city. Totally, 180 air samples were taken from 9 sampling stations from March 2018 to March 2019 and were analyzed to determine the concentrations of organic pollutants (BTEX compounds and PM2.5-bound PAHs) plus inorganic pollutants (PM2.5-bound metals and asbestos fibers). The results revealed that the mean concentrations of ∑ PAHs, BTEX, ∑ heavy metals, and asbestos fibers were 5.34 ng/m3, 60.55 µg/m3, 8585.12 ng/m3, and 4.13 fiber/ml in the cold season, respectively, and 3.88 ng/m3, 33.86 µg/m3, 5682.61 ng/m3, and 3.21 fiber/ml in the warm season, respectively. Source apportionment of emission of the air pollutants showed that PAHs are emitted from diesel vehicles and industrial activities. BTEX and asbestos are also released mainly by vehicles. The results of the inhalation-based risk assessment indicated that the carcinogenic risk of PAHs, BTEX, and asbestos exceeded the recommended limit by The US environmental protection agency (US EPA) and WHO (1 × 10–4). The risk of carcinogenesis of heavy metal of lead and chromium also exceeded the recommended limit. Thus, proper management strategies are required to control the concentration of these pollutants in Tehran's ambient air in order to maintain the health of Tehran’s citizens
Ultrasound‐assisted synthesis of FeTiO3/GO nanocomposite for photocatalytic degradation of phenol under visible light irradiation
No full textPhenolic compounds are dangerous pollutants in industrial effluents that have caused many human and environmental problems. These compounds are resistant to decomposition conventional biological systems. Photocatalytic treatment is amongst the most efficient technique for phenol removal from aqueous media. In this study, FeTiO3/GO nanocomposite was synthesized through the ultrasound‐assisted method. Structural, morphological, and optical properties of the synthesized nanocomposite were characterized by TEM, XRD, EDS, XPS, BET, TGA, FTIR, and UV–visible techniques. Optimum conditions for phenol photocatalytic degradation were obtained in 3% of GO content, 0.75 g/L nanocomposite dosage, and pH = 8. The degradation efficiency decreased by increasing phenol concentrations and complete mineralization was observed after 240 min of irradiation in optimum conditions. The effect of scavengers indicated that superoxide and hydroxyl radicals had the main role in the photodegradation process. The hindrance effect of inorganic ions was obtained asHCO3- > Cl- > SO42− > NO3-. Our experimental results put forward the FeTiO3/GO nanocomposite as a highly stable catalyst that can successfully remove phenolic compounds from aqueous solutions. Only a 10.8% decrease was observed in phenol degradation efficiency after five cycles, showing high recyclability of the FeTiO3/GO nanocomposite