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1.
Environ Monit Assess ; 192(4): 241, 2020 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-32189082

RESUMEN

The present study aimed to assess and monitor the therapeutic potential of antimicrobial metabolites from marine sponge-associated bacteria collected from the southeast coast of India against multidrug-resistant clinical bacterial isolates. Five sponge samples were collected and the metabolite-producing bacteria were screened from the Gulf of Mannar, India, and their antibacterial potential was studied against drug-resistant clinical bacterial isolates obtained from the hospitals. The two metabolite-producing bacteria (IS1 and IS2) were characterized by standard microbiology protocols and 16S rRNA sequencing. The antibacterial metabolites were characterized by liquid chromatography mass spectrometry (LCMS) analysis. The study suggested that marine sponges such as Spheciospongia spp., Haliclona spp., Mycale spp., Tedania spp., and SS-01 were associated with 30 ± 2, 26 ± 2, 23 ± 3, 21 ± 2, and 20 ± 2% of antibacterial metabolite-producing bacteria, respectively. The LCMS analysis of metabolites extracted from IS1 (4,6-dimethyl-2-pyrimidinamine; 4,5-dimethyl-2-propylsilyl-1H-imidazole) and IS2 (caproyl amide, 2-imidazoline) associated with Spheciospongia spp. exhibited significant antibacterial properties against drug-resistant bacteria. IS1 showed antimicrobial potential against the clinical isolates of Proteus spp., and IS2 showed antibacterial potential against isolates of both Proteus mirabilis and Salmonella typhi. IS1 and IS2 were identified by 16S rRNA sequencing and designated as Klebsiella spp. DSCE-bt01 and Pseudomonas spp. DSCE-bt02, respectively. The current study concluded that the assessment and monitoring of novel isolates from sponge-associated bacteria from marine coastal areas probably offer latest breakthrough in curtailing the global antimicrobial resistance and the study of such ecosystems adds value addition to the searching of novel bioactive compounds from terrestrial ecosystems.


Asunto(s)
Bacterias , Ecosistema , Monitoreo del Ambiente , Poríferos , ARN Ribosómico 16S , Animales , Antibacterianos , Monitoreo del Ambiente/métodos , India , Pruebas de Sensibilidad Microbiana , Filogenia , Poríferos/microbiología
2.
J Water Health ; 18(1): 1-7, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32129181

RESUMEN

Hospitals' effluents contain a considerable amount of chemicals. Considering the significant volume of wastewater discharged by hospitals, the presence of these chemicals represents a real threat to the environment and human health. Thus, the aim of this study was to evaluate the in vivo and in vitro genotoxicities of three wastewater effluents collected from Tunisian hospitals. The liver of Swiss albino male mice, previously treated with different doses of the hospital wastewaters, was used as a model to detect DNA fragmentation. Our results showed all the hospital effluents caused significant qualitative and quantitative hazards in hepatic DNA. The wastewater collected from Sfax hospital exhibited the highest genotoxic effect, which may be explained by the presence in this effluent of some toxic micropolluants. There was a significant increase in genotoxicity, proportionally to the concentration of effluent. However, the vitotox assay did not show any significant genotoxicity on Salmonella typhimurium TA104 in the presence or absence of microsomal fraction S9. The ratio gentox/cytox was lower than the threshold 1.5. This study assessed the toxicological risk issued from Tunisian hospital wastewaters, which is potentially very harmful, and it has been pointed out that wastewater treatment requires special attention.


Asunto(s)
Monitoreo del Ambiente/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/toxicidad , Animales , Daño del ADN , Hospitales , Humanos , Ratones , Contaminantes Químicos del Agua/análisis
3.
J Water Health ; 18(1): 8-18, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32129182

RESUMEN

Human mitochondrial DNA (mtDNA) genetic markers are abundant in sewage and highly human-specific, suggesting a great potential for the environmental application as human fecal pollution indicators. Limited data are available on the occurrence and co-occurrence of human mtDNA with fecal bacterial markers in surface waters, and how the abundance of these markers is influenced by rain events. A 1-year sampling study was conducted in a suburban watershed impacted by human sewage contamination to evaluate the performance of a human mtDNA-based marker along with the bacterial genetic markers for human-associated Bacteroidales (BacHum and HF183) and Escherichia coli. Additionally, the human mtDNA-based assay was correlated with rain events and other markers. The mtDNA marker was detected in 92% of samples (n = 140) with a mean concentration of 2.96 log10 copies/100 ml throughout the study period. Human mtDNA was detected with greater abundance than human-associated Bacteroidales that could be attributed to differences in the decay of these markers in the environment. The abundance of all markers was positively correlated with rain events, and human mtDNA abundance was significantly correlated with various bacterial markers. In general, these results should support future risk assessment for impacted watersheds, particularly those affected by human fecal pollution, by evaluating the performance of these markers during rain events.


Asunto(s)
ADN Mitocondrial , Monitoreo del Ambiente/métodos , Microbiología del Agua , Contaminantes del Agua/análisis , Bacteroidetes , Heces , Marcadores Genéticos , Humanos , Contaminación del Agua
4.
J Water Health ; 18(1): 19-29, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32129183

RESUMEN

Fecal contamination is one of the factors causing deterioration of Laguna Lake. Although total coliform levels are constantly monitored, no protocol is in place to identify their origin. This can be addressed using the library-dependent microbial source tracking (MST) method, repetitive element sequence-based polymerase chain reaction (rep-PCR) fingerprinting. Serving as a prerequisite in developing the host-origin library, we assessed the discriminatory power of three fingerprinting primers, namely BOX-A1R, (GTG)5, and REP1R-1/2-1. Fingerprint profiles were obtained from 290 thermotolerant Escherichia coli isolated from sewage waters and fecal samples of cows, chickens, and pigs from regions surrounding the lake. Band patterns were converted into binary profiles and were classified using the discriminant analysis of principal components. Results show that: (1) REP1R-1/2-1 has a low genotyping success rate and information content; (2) increasing the library size led to more precise estimates of library accuracy; and (3) combining fingerprint profiles from BOX-A1R and (GTG)5 revealed the best discrimination (average rate of correct classification (ARCC) = 0.82 ± 0.06) in a two-way categorical split; while (4) no significant difference was found between the combined profiles (0.74 ± 0.15) and using solely BOX-A1R (0.76 ± 0.09) in a four-way split. Testing the library by identifying known isolates from a separate dataset has shown that a two-way classification performed better (ARCC = 0.66) than a four-way split (ARCC = 0.29). The library can be developed further by adding more representative isolates per host source. Nevertheless, our results have shown that combining profiles from BOX-A1R and (GTG)5 is recommended in developing the MST library for Laguna Lake.


Asunto(s)
Dermatoglifia del ADN , Monitoreo del Ambiente/métodos , Lagos/microbiología , Contaminantes del Agua/análisis , Animales , Bovinos , Pollos , Heces/microbiología , Femenino , Filipinas , Reacción en Cadena de la Polimerasa , Porcinos
5.
Chemosphere ; 244: 125551, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32050345

RESUMEN

The distribution of Hg, Cd, Cu, and Zn in keratinized tissues, blood fractions, and excretory organs, and MTs in blood fractions and excretory organs was determined in captive, semicaptive, and wild Morelet's crocodiles and they were compared to select the most useful non-destructive tissues for the monitoring of metal exposure and to assess the potential of MTs as a biomarker. Our results indicate blood plasma, claws, and caudal scutes altogether are suitable tissues for xenobiotic metals exposure, with concentrations in blood plasma being an indicator of recent exposure, whereas concentrations in claws and caudal scutes are indicators of chronic exposure. Results in keratinized tissues suggest they are an important detoxification strategy in crocodiles, and claws presented the highest concentrations of metals in both captive (Hg = 0.44 ± 0.23 µg g-1, Cd = 11.10 ± 5.89 µg g-1, Cu = 45.98 ± 23.18 µg g-1, Zn = 124.75 ± 75.84 µg g-1) and wild populations (Hg = 1.31 ± 0.32 µg g-1, Cd = 26.47 ± 21.15 µg g-1, Cu = 191.75 ± 165.91 µg g-1, Zn = 265.81 ± 90.62 µg g-1). Thus, they are an appropriate tool for assessing metal exposure in populations where scutes clipping as a marking technique is not allowed, and their collection is less complicated than with other tissues. MTs are a suitable biomarker in blood plasma, whereas in erythrocytes detoxification processes might depend on hemoglobin, rather than MTs. Future studies should consider the implementation of these tools for the monitoring of wild populations.


Asunto(s)
Caimanes y Cocodrilos/sangre , Monitoreo del Ambiente/métodos , Metalotioneína/sangre , Metales/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Biomarcadores/sangre , Mercurio/análisis , Metales/análisis , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis
6.
Chemosphere ; 244: 125574, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32050349

RESUMEN

Chlorinated paraffins (CPs) are high production volume chemicals of which some show resistance to environmental degradation, long-rang transport, bioaccumulation and toxicity potential. Information regarding their presence in humans is limited, including their human bioaccumulation potential. The present study aimed to evaluate CP levels in human serum from Australia in order to better understand their exposure and current pollution status as well as trends associated with age and time between 2004 and 2015. For this, we selected a male sub-group of the Australian population under 60 years old (n = 16 pools, total 1600 serum samples). While long-chain CP (C18-20) and most short-chain CP (C10-13, SCCPs) levels were below method detection limits (MDL), medium-chain CPs (C14-17, MCCPs) were found in most serum samples (detection frequency 94%) as well as CPs with a carbon chain length of nine (detection frequency 76%). The levels of ΣSCCPs and ΣMCCPs ranged from

Asunto(s)
Exposición a Riesgos Ambientales/estadística & datos numéricos , Contaminantes Ambientales/metabolismo , Hidrocarburos Clorados/sangre , Parafina/metabolismo , Australia , Monitoreo del Ambiente/métodos , Contaminación Ambiental/análisis , Humanos , Hidrocarburos Clorados/análisis , Persona de Mediana Edad , Parafina/análisis
7.
Mikrobiyol Bul ; 54(1): 50-65, 2020 Jan.
Artículo en Turco | MEDLINE | ID: mdl-32050878

RESUMEN

Legionella bacteria living in free form or in biofilm and free-living amoebae (FLA) can infect humans through swimming pools and can cause various diseases. FLA may also threaten the health of swimmers because they are capable of being hosts for Legionella and some other bacteria. The aim of this study was to investigate the presence of total aerobic heterotrophic bacteria (TAHB), FLA and Legionella bacteria in swimming pool waters and biofilm samples in Istanbul by using culture and FISH methods. Water plate count agar (wPCA), buffered charcoal yeast extract (BCYE) agar supplemented with glycinevancomycin-polymyxin-cycloheximide (GVPC) and Escherichia coli cultivated non-nutrient agar (NNA) were used for the culture of TAHB, Legionella and FLA. For the FISH method analysis , Leg 705 and Leg PNE1 probes labeled with fluorescent dye for Legionella and ACANTHA probe for Acanthamoeba genus FLA were used. Legionella pneumophila serogroup 1 ATCC 33152, L.pneumophila serogroup 3 ATCC 33155 and Acanthamoeba castellani ATCC 50373 were used as positive controls. TAHB were grown in 92% and 84% of water and biofilm samples. Although Legionella bacteria could not be grown in any of the water samples, it was detected in 6 (24%) water samples by FISH method. Although these bacteria could be grown in 1 (4%) of biofilm samples, 7 (28%) were detected by FISH method. FLA were found to be 16% by culture in water samples and 28% by FISH analysis. These amoebae were detected 8% and 20% in biofilm samples by culture and FISH method, respectively. It was determined that one of the isolates of FLA had thermotolerant activity (potentially pathogenic). L.pneumophila serogroup 1 was detected in one water sample and in four biofilm samples. According to the culture method, TAHB and FLA were found to be more common in water samples than in biofilm samples and Legionella bacteria were more common in biofilm samples than in water samples (p≤ 0.05). In the detection of Legionella bacteria, the superiority of FISH method compared to culture method was found to be statistically significant (p≤ 0.05). In this study, it was found that the number of TAHB in the controlled swimming pools was within the limits determined by the Ministry of Health (≤ 200 cfu/ml). It will be appropriate to examine both water and biofilm samples for the investigation of TAHB, FLA and Legionella. It may be appropriate to use both culture and FISH methods to detect the presence of FLA in water and biofilm samples. This study is the first study to investigate the presence of Legionella and FLA in swimming pools in Istanbul, and further studies are needed to examine more pool water and biofilm samples. With the data obtained, the health principles and controls of swimming pools will be re-considered and will be contributed to public health.


Asunto(s)
Amoeba , Biopelículas , Monitoreo del Ambiente , Legionella , Piscinas , Microbiología del Agua , Agua , Amoeba/fisiología , Monitoreo del Ambiente/métodos , Incidencia , Legionella/fisiología , Turquia , Agua/parasitología
8.
Environ Monit Assess ; 192(3): 158, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32016573

RESUMEN

Faecal microorganisms represent a key threat to human health. Potential origins of faecal microbial contamination in a typical urban-representative micro-scale were evaluated. The quantitative polymerase chain reaction (qPCR) method was used in this study. The Bacteroidetes is selected as the indicative microorganism in runoff samples that are collected during four representative stormwater events in north China. The principal component analysis (PCA) method indicated the distribution feature of the environmental factors. The largest contributor is dog, followed by bird and human to the faecal pollution in stormwater runoff. The output of human and dog faecal pollutants in response to the first flush effect of nonpoint source pollution while the transmit time of bird faecal pollutant is relatively longer. In addition, the number of antecedent drying days represents the key factor for dog faecal pollution, while human faecal pollution is impacted by more factors. The results of this study will provide sound evidence for the tracking and management of nonpoint source faecal pollution in urban catchment areas.


Asunto(s)
Bacteroidetes , Monitoreo del Ambiente , Heces , Microbiología del Agua , Animales , China , Perros , Monitoreo del Ambiente/métodos , Contaminación Ambiental , Heces/microbiología , Humanos , Lluvia , Reacción en Cadena en Tiempo Real de la Polimerasa
9.
Mar Pollut Bull ; 150: 110779, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31910526

RESUMEN

This study was concerned with spatial analysis of mercury (Hg) in sediment samples of the USA coastal areas using more accurate and stable hybrid approaches compared to the conventional methods. An ensemble of simulated annealing along with least angle regression (SA-LAR) was applied for selection of predictors in spatial analysis. The latest algorithm was efficient with resultant RMSE and R2 of 0.066 and 0.705 compared to 0.099 and 0.571 for the traditional method of recursive feature elimination (RFE) approach. Using Cu, Pb and As as selected variables, it was tried to improve the spatial forecasting of Hg with either a hybrid of generalized boosted regression and ordinary kriging (GBROK) or inverse distance weighting (GBRIDW). According to the results, the variance explained by cross validation (VECV) was improved from 7.52% and 9.76% for IDW and OK to 40.41% and 41.94% for the GBRIDW and GBROK methods, respectively.


Asunto(s)
Monitoreo del Ambiente/métodos , Mercurio , Oligoelementos , Contaminación del Agua/estadística & datos numéricos , Análisis de Regresión , Análisis Espacial
10.
Environ Monit Assess ; 192(2): 73, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31897756

RESUMEN

Evolutionary algorithms (EAs) have become competitive solvers of a wide variety of water-resources optimization problems. Genetic programming (GP) has become a leading EA since its inception in 1985. This paper reviews the state-of-the-art of GP and its applications in water-resources systems analysis. A comprehensive knowledge about GP's theory and modeling approach is essential for its successful application in water-resources systems analysis. This review presents variants of GP that have been proven useful in various applications to water resources problems. Several examples of applications of GP in water-resources systems analysis are herein presented. This review reveals GP's capability and superiority compared to other conventional methods, which makes it suitable for solving a wide variety of water-related problems including rainfall-runoff modeling, streamflow sediment prediction, flood prediction and routing, evaporation and evapotranspiration forecasting, reservoir operation, groundwater modeling, water quality modeling, water demand forecasting, and water distribution systems.


Asunto(s)
Monitoreo del Ambiente/métodos , Recursos Hídricos , Algoritmos , Inundaciones , Predicción , Agua Subterránea , Modelos Teóricos , Análisis de Sistemas , Calidad del Agua
12.
Chemosphere ; 243: 125443, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31995890

RESUMEN

Long-term sampling is essential for monitoring the air pollutants emitted from stack since it can monitor the pollutants emission continuously including the stages of start-up, shutdown and normal operation. However, commercial continuous sampling equipment such as AMESA faces the challenges of high weight and complicated sampling procedures. This study has developed a long-term and automatic sampling system (National Central University continuous stack sampling system, NCU-CS3), and compared the efficiency with manual sampling train (MST). The results indicate that relative standard deviation (RSD) of PCDD/Fs concentrations measured between NCU-CS3 and MST is <20%, demonstrating that the difference between NCU-CS3 and MST in measuring PCDD/Fs is insignificant. Besides, the effects of adsorbent temperature, adsorbent amount and type of adsorbent on breakthroughs of PAHs and unintentional-persistent organic pollutants (UPOPs) such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), chlorinated phenols (CPs), chlorinated benzenes (CBs) and polychlorinated naphthalenes (PCNs) are evaluated. The results indicate that the breakthrough of pollutants increases with increasing temperature of XAD-2 and decreases with increasing XAD-2 amount. Moreover, XAD-4 is used as alternative adsorbent to test the breakthrough and the results indicate that the breakthroughs of UPOPs of XAD-4 as adsorbent are lower than that with XAD-2 due to higher specific surface area of XAD-4. Furthermore, the residual of PCDD/Fs with NCU-CS3 as the sampling train is relatively low (1.5-3.8%), which meets the regulation of EN 1948-5 (10%).


Asunto(s)
Contaminantes Atmosféricos/análisis , Dibenzofuranos Policlorados/análisis , Monitoreo del Ambiente/métodos , Compuestos Orgánicos/análisis , Dibenzodioxinas Policloradas/análisis , Benzofuranos/análisis , Dibenzofuranos/análisis , Contaminantes Ambientales/análisis , Estudios Longitudinales , Naftalenos/análisis , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisis
13.
Chemosphere ; 243: 125442, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31995889

RESUMEN

Bathing in natural waters is a highly demanded recreational activity in tropical countries because of climatic conditions and availability of bathing sites; but, do users know the water quality of these sites? We determined the physicochemical and microbiological water quality of a highly used bathing site in southern Ecuador. We assessed how bather attendance, rainfall events, and pool location alters the recreational water quality (RWQ). Most of the parameters measured in the stream pools did not accomplish the Ecuadorian and international regulations for recreational water quality. Microbiological water quality diminishes from upstream to downstream pools because of human activities and bathing intensity having potential effects on bather health and eco-touristic development. We found that an increase of bathers is strongly associated with a growing concentration of Escherichia coli. It is suggested better land-use practices and review thoroughly the Ecuadorian regulation to assure a healthy RWQ. Further efforts are needed to identify more risky bathing sites, determine pollution sources, and establish a long-term monitoring program to support the touristic development in countries looking for diversifying their economy.


Asunto(s)
Playas/normas , Monitoreo del Ambiente/métodos , Calidad del Agua , Ecuador , Escherichia coli/aislamiento & purificación , Humanos , Microbiología del Agua/normas
14.
Environ Monit Assess ; 192(2): 81, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31897611

RESUMEN

Ecological quality (EcoQ) status of the Southwest and West coasts of South Korea was evaluated within the "National Investigation of Marine Ecosystems in Korea" in the 2015. In particular, the study dealt to assess the ecological quality of the sediments using free-living nematode communities. A total of 149 species were found in the study area, and Daptonema, Sabatieria, Parodontophora, Sphaerolaimus, and Viscosia were found as dominant genera. Statistical analysis of both environmental and faunal parameters showed an increasing human pressure from Western to Southern coasts. The community structure changed with the environmental features of the study area and allowed the detection of a suite of possible nematode indicators that might be used in monitoring studies. In particular, Dorylaimopsis spp. appeared heavy metal and organic matter resistant taxa, Sabatieria an eutrophication resistant genus, while Paracanthonchus and Neotonchus as heavy metal and organic matter sensitive genera. The principal component analysis (PCA) results showed a clear negative correlation between maturity index and both heavy metal and organic matter increasing, while diversity indices did not appear to be significantly influenced by them. Appling the thresholds of the synthetic nematode indices, the EcoQ of the study area was assessed as poor to moderate.


Asunto(s)
Ecosistema , Monitoreo del Ambiente/métodos , Nematodos/fisiología , Contaminación del Agua/análisis , Animales , Ecología , Eutrofización , Sedimentos Geológicos/química , Actividades Humanas , Metales Pesados , República de Corea
15.
Environ Monit Assess ; 192(2): 72, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31897765

RESUMEN

This study presents the use of Quick Easy Cheap Efficient Rugged and Safe (QuEChERS) as an effective sample cleaning procedure and switchable solvent liquid phase microextraction (SS-LPME) as a preconcentration tool for the determination of fenazaquin by gas chromatography mass spectrometry (GC-MS) at ultratrace levels. After a thorough optimization process, 0.50 mL of switchable solvent, 1.5 mL of 1.0 M sodium hydroxide, and 15 s of vortexing were determined as optimum conditions of the SS-LPME method. The limit of detection (LOD) and limit of quantitation (LOQ) determined using the optimum method (SS-LPME/GC-MS) were 0.05 and 0.18 ng/mL, respectively. Compared with direct GC-MS determination of fenazaquin, the optimum method yielded about 800-fold enhancement in detection power of GC-MS. The method was applied to lake, irrigation canal, well, and wastewater samples. In order to test the method's applicability on fresh tomato samples, a QuEChERS method was used before applying the SS-LPME method. Matrix-matched calibration standards were used to enhance the accuracy of fenazaquin quantification in spiked tomato samples to obtain recovery results close to 100%.


Asunto(s)
Lycopersicon esculentum/química , Quinazolinas/análisis , Contaminantes Químicos del Agua/análisis , Agua/química , Monitoreo del Ambiente/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Lagos/análisis , Límite de Detección , Microextracción en Fase Líquida/métodos , Solventes/química , Aguas Residuales/química , Agua/análisis
16.
Environ Monit Assess ; 192(2): 82, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31897757

RESUMEN

Bacterial contamination occurs in different occupational exposures. Although the level of colony-forming units in airborne samples reveals bacterial exposure, the bacterial origin is not specified. We applied Fourier transform infrared spectroscopy to investigate bacterial species in airborne samples and validated bacterial evaluation in an occupational exposure. As a pilot study, airborn of nurses station (n=40) was assessed according to National Institute of Occupational Safety and Health 0800 method. Bacterial strain in all samples was evaluated by diagnosis gallery tests. Simultaneously, Fourier transform infrared spectroscopy of sampled bacteria was prepared and then classified by principal component analysis. Spectroscopy method was validated for Staphylococcus aureus quantification. For this aim, spectrum band area in different wavenumbers was evaluated for calibration curve plotting and extraction of validation parameters. The second derivatization of spectroscopy data in 1200 to 1500 cm-1 presented the best determination for gram-type discrimination by principal component analysis modeling. Moreover 900-1200 cm-1 region modeling finely differentiated gram-negative bacteria in airborne samples. Adding spectroscopy area band in 2850 and 2906 cm-1 was validated to assess the level of Staphylococcus aureus contamination. Results showed appropriate correlation between the Staphylococcus aureus level in airborne samples analyzed by commercial counting evaluation and Fourier transform infrared spectroscopy method. Fourier transform infrared spectroscopy is a functional technique for assessment of airborne quality in occupational exposure. This analysis was recommended as an alternative method for quantitative and qualitative analysis of bio-aerosols.


Asunto(s)
Microbiología del Aire , Bacterias , Monitoreo del Ambiente/métodos , Exposición Profesional/análisis , Aerosoles/análisis , Bacterias Gramnegativas , Humanos , Exposición Profesional/estadística & datos numéricos , Proyectos Piloto , Análisis de Componente Principal , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus
17.
Environ Monit Assess ; 192(2): 75, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31897783

RESUMEN

Content of some heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) and macroelements (Ca, Mg, Na, and K) were determined in samples of water, sediment, macrophytes (Potamogeton crispus, Potamogeton perfoliatus, Myriophyllum spicatum, and Chara vulgaris), and leech (Hirudo sulukii n. sp.) collected from Kara Lake Adiyaman, Turkey at four distinct seasons using inductively coupled plasma optical emission spectrometer (ICP-OES). It was found that the studied heavy metals were completely below the detection limit of ICP-OES for water samples. The results showed that most heavy metals (Ni, Cr, Zn, Fe, and Pb) and macroelements (Mg and Na) had their highest values in sediment samples in August. Increases of heavy metals and macroelements may be due to evaporation because of summer stagnation at this period. The average content of studied elements was in the order of Mn>Ni>Cr>Zn>Fe>Pb>Cu in sediment samples. As a non-essential heavy metal, Cr was the most accumulated in all the macrophytes studied. The average Cr concentration was in the order of P. crispus > P. perfoliatus > M. spicatum > C. vulgaris. In C. vulgaris, the accumulation of Ca was the highest compared with other macrophytes. The accumulation of heavy metal was in the order of Fe>Zn>Cu>Pb>Mn>Cr>Ni>Cd in H. sulukii n. sp. The obtained results showed that the heavy metal and macroelement (Na, Ca, Mg, and K) concentrations in water, sediment, macrophytes, and leech are below the risk values according to the aquatic life pollutant data provided by the U.S. Environmental Protection Agency. Overall, the element contents can be attributable to the geological sources because of the general absence of serious pollution in Kara Lake, Adiyaman, Turkey.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Animales , Contaminación Ambiental , Gastrópodos , Sedimentos Geológicos , Lagos/química , Potamogetonaceae , Estaciones del Año , Turquia , Agua
18.
Environ Monit Assess ; 192(2): 76, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31897800

RESUMEN

Per- and polyfluoroalkyl substances (PFASs) have attracted attention due to the potential risk they pose to ecosystems and human health. A total of 169 groundwater samples were collected from four representative regions in order to analyze PFASs concentrations in China. The total concentration of PFASs (∑PFASs) in groundwater ranged from 0.05 to 198.80 ng L-1, with an average of 3.97 ng L-1. All targeted PFASs were detected in the studied areas. The detection frequency and average concentration of perfluorooctanoic acid (PFOA) were the highest (79.29% and 1.61 ng L-1, respectively). The contamination profiles of PFASs in each study area varied due to natural geographical conditions and human activities. According to the results of the potential source identification, the point sources of perfluorooctane sulfonate (PFOS) were mainly concentrated in Lanzhou, and the distribution of PFASs was slightly affected by atmospheric deposition in all the studied areas. The obtained concentrations of PFOA and PFOS may pose no threat to the residents due to water consumption.


Asunto(s)
Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Ácidos Alcanesulfónicos , Caprilatos , China , Ecosistema , Fluorocarburos , Agua Subterránea/química , Humanos , Medición de Riesgo
19.
Environ Monit Assess ; 192(2): 78, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31899536

RESUMEN

Food scarcity is one of global issues that our world faces today. A significant portion of the world's population has no access to adequate food, and it is stated that approximately 830 million people suffer from chronic famine. This predicament is estimated to grow even further. Many attempts have been made to solve the food problem. Some examples are using new resources which have not been used for dietary purposes up to this point, planting new areas to produce food products, and increasing the potential harvest per an area unit. One of the solution proposals, which has come up recently within this scope, is the term of "edible landscaping", which means the use of edible plants in the landscaping works, and thus maximizing the potential for food security. However, edible landscaping poses a considerable risk. Heavy metal accumulation in plants grown in urban centers can reach to high levels, and consuming these plants will allow these heavy metals a direct access into the human body and wreak havoc to the public health. But since this subject has not been sufficiently studied yet, the extent of such a risk is not accurately determined yet. This study aims to determine the changes of Ni, Co and Mn concentrations depending on traffic density in the leaves, branches, barks and fruits of cherry, plum, mulberry and apple trees growing in areas with dense traffic, low-density traffic and no-traffic zones in Kastamonu province. The results showed that the concentrations of Ni and Co elements increased in many organelles depending on traffic density, and that the heavy metal concentrations in fruits could be very high. This situation indicates that fruit and vegetables grown in industrial zones and urban centers, where heavy metal pollution may be high, can be harmful to the public health if consumed as crops.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Plantas Comestibles/química , Contaminación por Tráfico Vehicular/análisis , Emisiones de Vehículos/análisis , Contaminación Ambiental/análisis , Humanos , Contaminantes del Suelo/análisis
20.
Environ Monit Assess ; 192(2): 95, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-31907629

RESUMEN

With the acceleration of urbanization and industrialization, atmospheric pollution has become a major issue, restricting the sustainable development of the urban environment. Since 2013, Beijing has been among China's most seriously affected regions in terms of haze pollution. Atmospheric pollution is closely linked to land use, particularly the spatial patterns of green and urban land. Therefore, the quantification of the relationship between fine particulate matter (PM2.5) concentration and its driving factors in Beijing is of considerable significance for environmental management and spatial epidemiological studies. A land use regression (LUR) model was constructed to simulate the spatio-temporal distribution of PM2.5 concentration. In this study, the independent variables (driving factors) included land use, meteorological factors, population, roads, the digital elevation model, and the normalized difference vegetation index. The five models had adjusted R2 of 0.887, 0.770, 0.742, 0.877, and 0.798, respectively. Land use and meteorological factors were the main factors affecting PM2.5 concentration. The driving factors of land use on a large scale and roads on a small scale had a significant impact on PM2.5 emissions. Beijing's PM2.5 concentrations in 2015 showed clear spatio-temporal characteristics. The highest (lowest) average PM2.5 concentration was recorded in winter (summer). In terms of spatial distribution, PM2.5 concentrations showed a "low in the northwest and high in the southeast" trend. The most polluted areas were mainly distributed in the central city and the southeastern and southwestern regions. The PM2.5 concentration boundary was essentially consistent with the boundary of land use type. Different land use types promoted or inhibited PM2.5 concentrations, with a difference of more than 20 µg/m3 PM2.5 between the two land use categories. Thus, PM2.5 concentrations should be controlled by optimizing the spatial and temporal patterns of land use.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Contaminación Ambiental/análisis , Material Particulado/análisis , Beijing , China , Planificación de Ciudades , Estaciones del Año , Urbanización
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