11 research outputs found

    Tracking of chloramphenicol, erythromycin, and sulfamethoxazole antibiotic-resistant bacteria from untreated wastewater effluents to receiving river

    Get PDF
    Background: The aim of this study was to investigate the frequency and type of bacteria resistant to chloramphenicol (CHL), erythromycin (E), and sulfamethoxazole (SXT) antibiotics from untreated wastewater effluents to receiving river. Methods: In total, 32 samples were taken from eight sites located in the raw wastewater to the downstream of the receiving Ghotor river in Khoy city. Resistant microorganisms were studied through modified HPC method and CLSI standards. Different and specific colonies were selected and re-cultured in R2A culture medium and enough colonies were used for DNA extraction. Bacterial 16sr RNA target gene was amplified and sequenced. Pseudomonas sp., Comamonas sp., and Thiobacillus sp. were predominant bacterial species identified in water samples. Also, antibiotic-resistant genes (ARGs) including sul1, ermB, and cmlA1 were tracked by PCR. Results: The average total number of antibiotic-resistant bacteria (ARB) increased in the downstream (2.4×102 to 2.6×104 CFU/100 mL). The comparison of the results related to the river’s upstream and downstream also indicated a significant difference between ARB and ARGs contents (P<0.05). The average number of bacteria resistant to SXT, E, and CHL antibiotics was obtained to be 2.3×104, 2.3×104, and 3.4×104 CFU/mL, respectively. Finally, the evaluation of water revealed that only the aeration lagoon was able to decline the number of CHL-resistant bacteria (88.9%) while this process increased the number of SXT- (51%) and E- (16%) resistant bacteria. The lowest and highest percentages of the identified genes were related to ermB (12.5%) and sul1 (81.25%), respectively. Conclusion: According to the results, wastewaters play an important role in releasing ARB and their antibiotic resistance genes to downstream of Ghotor rivers in Khoy city. Keywords: Heterotrophic bacteria, Sulfamethoxazole, Chloramphenicol, Erythromycin, Polymerase chain reaction, Wastewater, River

    Environmental literacy Education to Promote Environmental Protection Behaviors

    No full text
    Environmental protection and preservation have become one of the most important issues of human societies today. Various studies have shown that among the various ways of addressing environmental problems, the most fundamental, effective, and cost-effective method to prevent environmental destruction is through the observance of environmental protection behaviors by humans. Therefore, to achieve this goal, we need environmental literacy education. This literacy should identify and respond sensitively to the complex and changing communications between humans and nature. Environmental literacy education increases people's awareness of the environment and the use of environmental information to improve it. To promote environmental literacy and protect the environment, the following three educational areas are proposed: 1. Environmental literacy in the cognitive domain: We enhance people's awareness and sensitivity to the environment and related problems. 2. Environmental literacy in the attitudinal domain: In this domain, obtaining a set of values and feelings of concern for the environment and motivating individuals to actively participate in improving and protecting the environment will be effective.3. Environmental literacy in the behavioral domain: In this domain, by considering environmental concerns in daily activities, environmental literacy education can promote the use of behaviors that reduce the adverse effects of the environment

    Determine the Integrated Indicators of Air Quality, Radiation, Sound and Lead of the Delphi Technique

    No full text
    Background: With Regard to importance of environmental health issues in recent decades, coherent and planned efforts to identify environmental health indicators and values and how it is controlled. Primarily for evaluation and monitoring for each subject should be determined the indicators also indicators for the evaluation of air quality should be considered. In the present study Addressed to survey of indicators of air quality, radiation, sound and heavy metals to Iran. Methods: In the present study is that all countries in the world in terms of air quality, Radiation, sound and heavy metals (lead and mercury) are to be examined And according to these criteria, indicators that are commensurate with our country elected. For each of these indicators, the indicators and methods of calculation are determined. Results: During this study was about 35 indicator Given the importance of health and the environment, it is calculated and information about the index, an indicator of air quality, radiation, sound and heavy metals, 16, 1, 1 and 0 in the first two years of the first respectively. Conclusion: Among the indicators selected at the beginning of what exists and what indicators in this study were obtained, As can be seen from the 35 indicators surveyed, There are 13 indicators in the country and 22 of the present investigation was added

    Environmental cycle of antibiotic resistance encoded genes: A systematic review

    Get PDF
    Antibiotic-resistant bacteria and genes enter the environment in different ways. The release of these factors into the environment has increased concerns related to public health. The aim of the study was to evaluate the antibiotic resistance genes (ARGs) in the environmental resources. In this systematic review, the data were extracted from valid sources of information including ScienceDirect, PubMed, Google Scholar and SID. Evaluation and selection of articles were conducted on the basis of the PRISMA checklist. A total of 39 articles were included in the study, which were chosen from a total of 1249 papers. The inclusion criterion was the identification of genes encoding antibiotic resistance against the eight important groups of antibiotics determined by using the PCR technique in the environmental sources including municipal and hospital wastewater treatment plants, animal and agricultural wastes, effluents from treatment plants, natural waters, sediments, and drinking waters. In this study, 113 genes encoding antibiotic resistance to eight groups of antibiotics (beta-lactams, aminoglycosides, tetracyclines, macrolides, sulfonamides, chloramphenicol, glycopeptides and quinolones) were identified in various environments. Antibiotic resistance genes were found in all the investigated environments. The investigation of microorganisms carrying these genes shows that most of the bacteria especially gram-negative bacteria are effective in the acquisition and the dissemination of these pollutants in the environment. Discharging the raw wastewaters and effluents from wastewater treatments acts as major routes in the dissemination of ARGs into environment sources and can pose hazards to public health

    Cefixime removal via WO3/Co-ZIF nanocomposite using machine learning methods

    No full text
    Abstract In this research, an upgraded and environmentally friendly process involving WO3/Co-ZIF nanocomposite was used for the removal of Cefixime from the aqueous solutions. Intelligent decision-making was employed using various models including Support Vector Regression (SVR), Genetic Algorithm (GA), Artificial Neural Network (ANN), Simulation Optimization Language for Visualized Excel Results (SOLVER), and Response Surface Methodology (RSM). SVR, ANN, and RSM models were used for modeling and predicting results, while GA and SOLVER models were employed to achieve the optimal conditions for Cefixime degradation. The primary goal of applying different models was to achieve the best conditions with high accuracy in Cefixime degradation. Based on R analysis, the quadratic factorial model in RSM was selected as the best model, and the regression coefficients obtained from it were used to evaluate the performance of artificial intelligence models. According to the quadratic factorial model, interactions between pH and time, pH and catalyst amount, as well as reaction time and catalyst amount were identified as the most significant factors in predicting results. In a comparison between the different models based on Mean Absolute Error (MAE), Root Mean Square Error (RMSE), and Coefficient of Determination (R2 Score) indices, the SVR model was selected as the best model for the prediction of the results, with a higher R2 Score (0.98), and lower MAE (1.54) and RMSE (3.91) compared to the ANN model. Both ANN and SVR models identified pH as the most important parameter in the prediction of the results. According to the Genetic Algorithm, interactions between the initial concentration of Cefixime with reaction time, as well as between the initial concentration of Cefixime and catalyst amount, had the greatest impact on selecting the optimal values. Using the Genetic Algorithm and SOLVER models, the optimum values for the initial concentration of Cefixime, pH, time, and catalyst amount were determined to be (6.14 mg L−1, 3.13, 117.65 min, and 0.19 g L−1) and (5 mg L−1, 3, 120 min, and 0.19 g L−1), respectively. Given the presented results, this research can contribute significantly to advancements in intelligent decision-making and optimization of the pollutant removal processes from the environment

    Enhancement of the catalytic performance of Co-ZIF/WO3 heterostructures for selective catalytic reduction of NOx

    No full text
    Abstract Nitrogen oxides (NOx) are one of the growing air pollutants in industrial countries, and their emissions are regulated by stringent legislation. Therefore, the design of the catalyst comprised of metal oxides and ZIFs a potential solution for improving selective catalytic reduction (SCR) of NOx. Here, an efficient strategy was described to fabricate Co-ZIF/WO3 heterostructures for SCR of NOx. First, WO3 nanostructures were fabricated by the solvothermal method, and subsequently epitaxial growth of ZIF-67 on the metal oxide surface to create a new type of semiconductor Co-ZIF/WO3 heterostructures. The obtained heterostructures were systemically characterized by wide-angle XRD, FESEM, UV DRS, FT-IR, AFM, and TEM spectroscopies. The Co-ZIF/WO3 heterostructures shift the temperature corresponding to the maximum conversion around 50 °C towards lower temperatures. The maximum conversion is substantially enhanced from 55% at 400 °C to 78% at 350 °C. The enhanced activity is attributed to better interaction and synergic effect of WO3 incorporated into ZIF-67 and also the electron transfer facility between the WO3 and Co species in Co-ZIF/WO3 heterostructures. Moreover, Co-ZIF/WO3 results in a distinct effect on the production of carbon monoxide (CO) in the product gas stream. The current study highlights some of the challenges in the development of semiconductor-based heterostructures for a decrease in air pollution

    Identification of clinically antibiotic resistant genes Aac(3)-IIa and Aac(6’)-Ib in wastewater samples by multiplex PCR

    No full text
    Background: Aminoglycoside antibiotics are widely used in medical centers, particularly to treat infections. The resistance developed against these agents is a huge concern in health care. A number of researchers have reported that hospital and municipal wastewaters are among the most important dissemination sources of these agent into the environment. Some, however, do not agree with this opinion. In the present study, the prevalence of aminoglycoside resistance genes was investigated in raw and effluent wastewater from hospital and municipal wastewater treatment plants. Methods: To conduct this descriptive-analytical study, 30 samples were taken according to sampling principles and cold cycle and transferred to the molecular laboratory. DNA was extracted by the freeze-thaw method using a kit (Promega). The genes aac(3)-IIa and aac(6’)-Ib which code aminoglycoside resistance were examined in this study. Results: The results indicated that the studied genes are present in 35% of urban and hospital wastewaters, and their frequency percentage is higher in hospital wastewater (52%) than urban wastewater (48%). The studied genes were identified in 61% of raw hospital wastewater samples; however, they were not detected in the output wastewater from the studied treatment plants. Conclusion: Although, the studied genes were not detected in the final effluent, there is a high potential for their release into the environment. The current study demonstrated that the coding genes of aminoglycoside antibiotic resistance are present in raw urban and hospital wastewaters. In the case of improper exploitation of wastewater treatment plants, the output water can contaminate other environmental sections, such as soil and water resources, and result in the emission of these contaminants

    Monitoring and eco-toxicity effect of paraben-based pollutants in sediments/seawater, north of the Persian Gulf

    No full text
    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
    corecore