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In this study, the degradability of the antibiotic Ceftriaxone was investigated with the help of genetically engineered Pseudomonas putida, in which the gene producing the enzyme catechol 2 and 3 dioxygenase was designed and then inserted into the pUC18 plasmid and replicated by E. coli. It was purified and extracted and transformed into Pseudomonas putida. Finally, the degradation rate of Ceftriaxone by this bacterium in spiked soil was evaluated using the HPLC measurement technique. Finally, the kinetics of Ceftriaxone degradation by genetically engineered Pseudomonas putida was investigated using zero, first, and second -order kinetic models for all factors. The results of HPLC measurement showed that the biodegradation of ceftriaxone in spiked soil was significant by genetically engineered P. putida compared to autoclaved soil inoculated by wild P. putida and normal soil with normal microbial flora (p<0.001) and this bacterium was able to degrade ceftriaxone by 69.53% and kinetic modeling showed that the rate of removal by genetically engineered Pseudomonas putida follows the zero-degree reaction model. These findings indicate that Pseudomonas putida, which produces Catechol 2,3-dioxygenase, can be useful and practical in the biological treatment of environment from cephalosporins. [ABSTRACT FROM AUTHOR]

Background: Nowadays, increasing the use of pesticides to manage the agriculture production resulted in increased pesticide residues in final products and concerns about environmental pollution and prevalence of emerging diseases. This study aims to investigate the residual amount of Phosalone toxin in the early and late varieties of peach orchards in Saman city located in Chaharmahal and Bakhtiari province. Methods: In this study, 60 samples of early and late peach varieties of peach orchards were selected randomly. Phosalone residues in early and late peach varieties before and after washing, and after peeling were extracted by QUECHERS method and the amount of extracted toxin were measured by high-performance liquid chromatography (HPLC). The data were analyzed using SPSS v.24 software. Results: Phosalone residues in early peach varieties before and after washing were 3.55 ± 0.94 and 0.31 ± 0.29 mg/kg, respectively. The concentration of Phosalone residues in unwashed early and late peach varieties before washing was 3.17 ± 0.97 mg/kg but decreased to 0.64 ±0.74 mg/kg after washing. Peeling reduced 97.79% of the Phosalone residues in late peach. Early and late peaches covered by the plant pathology clinic and unwashed late peaches not covered by plant pathology clinic were significantly (P < 0.05) higher than the Iranian national standard (2 mg/kg). Conclusion: Washing and peeling the peach significantly decreased the toxin residues. In order to minimize the risk of exposure to Phosalone residues, integrated pest control management programs are essential. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons have adverse effects on the organisms, plants, and soil structure. Therefore, they should be removed by an appropriate and effective method. In this study, simultaneous removal of 500 mg/kgsoil of phenanthrene and pyrene was investigated for the individual and combined application of Tween 80, Triton X-100, and sodium persulfate from the alluvial soil. The results revealed that the maximum removal efficiencies of phenanthrene (94.06 ± 0.30%) and pyrene (90.07 ± 0.19%) were observed in the presence of Triton X-100 + sodium persulfate (0.5 M) within 1 hour, respectively. Also, individual application of surfactants and sodium persulfate had efficiencies of less than 80%. It should be noted that the removal of phenanthrene and pyrene followed the first-order kinetic model. Economic evaluations of combined treatment demonstrated that the application of more proportion of Triton X-100 (10000 mg/L) + less proportion of sodium persulfate (0.3 M) is more cost-effective for the remediation of soil in the field study. Based on the results, the combined application of the washing process by Triton X-100 and persulfate oxidant can significantly improve the removal efficiencies and is a promising technique in the remediation of polycyclic aromatic hydrocarbons contaminated soil. [ABSTRACT FROM AUTHOR]

Background. PM2.5 emission is known as a major challenge to environmental health and is the cause of approximately 7 million deaths annually. This study aimed at investigating the main patterns of PM2.5 trend changes among European countries. Methods. The annual exposure to PM2.5 pollutants was retrieved from the World Bank for 41 countries during 2010 to 2017, and a latent growth model was applied to identify the main patterns using Mplus 7.4 software. Results. Monitoring the overall mean annual exposure to PM2.5 in the Europe showed a downward pattern with an annual decrease of 2.48% during the study period. Turkey had the highest PM2.5 exposure with 43.82 μg/m3 in 2010, reaching 44.31 μg/m3 in 2017. Likewise, with 7.19 μg/m3 in 2010, Finland had the lowest exposure level which decreased to 5.86 μg/m3 in 2017. Two main patterns for the mean annual PM2.5 exposure were identified via the latent growth model. Countries in the first pattern, including Turkey and Ukraine, had experienced a slow annual increase in the mean exposure of PM2.5 pollutant. Likewise, the other 39 countries belonged to the second pattern with a moderate falling trend in the mean exposure to PM2.5. Conclusion. Although the trend changes of mean annual exposure to PM2.5 in Europe were falling, Turkey and Ukraine had experienced a slow annual increase. It is advisable to take appropriate measures to curb the current raising exposure to PM2.5 in Turkey and Ukraine. [ABSTRACT FROM AUTHOR]

Background: PM 2.5 emission is known as a major challenge to environmental health and is the cause of approximately 7 million deaths annually. This study aimed at investigating the main patterns of PM 2.5 trend changes among European countries., Methods: The annual exposure to PM 2.5 pollutants was retrieved from the World Bank for 41 countries during 2010 to 2017, and a latent growth model was applied to identify the main patterns using Mplus 7.4 software., Results: Monitoring the overall mean annual exposure to PM 2.5 in the Europe showed a downward pattern with an annual decrease of 2.48% during the study period. Turkey had the highest PM 2.5 exposure with 43.82  μ g/m 3 in 2010, reaching 44.31  μ g/m 3 in 2017. Likewise, with 7.19  μ g/m 3 in 2010, Finland had the lowest exposure level which decreased to 5.86  μ g/m 3 in 2017. Two main patterns for the mean annual PM 2.5 exposure were identified via the latent growth model. Countries in the first pattern, including Turkey and Ukraine, had experienced a slow annual increase in the mean exposure of PM 2.5 pollutant. Likewise, the other 39 countries belonged to the second pattern with a moderate falling trend in the mean exposure to PM 2.5 ., Conclusion: Although the trend changes of mean annual exposure to PM 2.5 in Europe were falling, Turkey and Ukraine had experienced a slow annual increase. It is advisable to take appropriate measures to curb the current raising exposure to PM 2.5 in Turkey and Ukraine., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 Mahdiyeh Alikhani Faradonbeh et al.)