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Screening and Absolute Quantification of a β-lactamase Resistance Gene NDM-1 in Lake Sediment 全文
2022
Ranjan, Rajeev | Thatikonda, Shashidhar
New Delhi Metallo-β-lactamase-1(NDM-1) is an enzyme that hydrolyzes a wide range of β-lactams antibiotics, including carbapenems. The presence of the NDM-1 inhibits the potential of β–lactam antibiotics in treating infections caused by bacterial strains carrying such resistances, thus leaving minimal treatment options available. Due to this, the rapid distribution of NDM-1 harboring bacteria accounts for a significant public health menace worldwide. These bacteria have been detected in clinical specimens and environmental compartments where bacterial infections are ubiquitous. In this study, identification and absolute quantification of NDM-1 in sixteen lake sediment samples collected in and around Hyderabad, India, was carried out using a real-time quantitative polymerase chain reaction (qPCR), and the results were expressed in gene copy number/ng (nanogram) of template DNA. Thirteen samples (out of sixteen) displayed a positive signal for NDM-1 during the qPCR analysis with the highest gene copy number/ng of template DNA (71.8) being observed in the Amberpet STP. Three samples, samples from Durgamcheru lake, Kandi lake, and Singur dam, were negative for the NDM-1 during the qPCR analysis. Hierarchical clustering analysis was performed to categorize the sampling location into different clusters based on pollution sources and the observed results were expressed in the form of a dendrogram.
显示更多 [+] 显示较少 [-]Human health risk assessment via the consumption of platycephalus indicus in the Persian Gulf, Iran 全文
2022
Gholizadeh, Mohammad | Mohammadzadeh, Behroz | Kazemi, Ali
The assessment of human health risk associated with accumulation of lead, copper, zinc, nickel, and Arsenic in the muscle of bartail flathead (Platycephalus indicus) collected from Jofreh pier and Bushehr port, northwest of the Persian Gulf of Iran was examined. A total of 80 P. indicus were collected and analysed using ICP-OES from two seasons (summer and winter) of 2019; estimated daily intake (EDI), estimated weekly intake (EWI), target hazard quotient (THQ), hazard index (HI) and Carcinogenic risk (CR) were determined. The mean concentration (μg/g) range were observed as: zinc (16.37-50.17)> As (5.65-8.83)> Cu (2.19-3.63)> Pb (0.62-6.37)> Ni (0.17-1.08). Hazard index (HI) for adult and children during consumption of P.indicus was <1, the highest HI values were calculated for adults (0.06) in Bushehr and children (0.14) in Jofreh. The CR levels for Ni and Pb were within acceptable limits (10-6 to 10-4) and arsenic was unacceptable (> 10-4) at sampling sites.
显示更多 [+] 显示较少 [-]Assessment of the limnological characteristics of Lake Bosomtwe in the Ashanti Region of Ghana 全文
2022
Owusu-Boateng, Godfred | Ampofo-Yeboah, Akwasi | Agyemang, Thomas Kwaku | Sarpong, Kofi
The quality of the water from Lake Bosomtwe was assessed to aid in the conservation decision on the lake. Twenty-six parameters of physico-chemical, bacteriological, and organic effects and major and trace ions were evaluated using the principal component analysis. The levels of these parameters were also compared with surface water benchmarks of Ghana EPA, WHO, EU, US EPA and CCEM. As prescribed by the benchmarks of these regulatory bodies, the mean levels of temperature, pH, dissolved oxygen, total suspended solids, total dissolved solids, nitrates, phosphate, biochemical oxygen demand, chemical oxygen demand, total hardness, conductivity, alkalinity, turbidity and fluorine did not signal any lake pollution, but sulphate, total and faecal coliforms, chlorophyll-a, cadmium and mercury showed pollution tendencies. Temperature, pH, dissolved oxygen, total suspended solids, total dissolved solids, nitrates, phosphate, sulphate and total coliform bacteria were found to be the main parameters that drive 71.2% of the limnological characteristics of the lake water and deserve careful consideration in designing conservation strategies for the lake.
显示更多 [+] 显示较少 [-]Determination of Heavy metals in honey samples from different region of the north-east of Algeria: according to an urban gradient 全文
2022
Bouden, Mohammed Chafik | Belabed, Ibrahim Adnene
This study aims to assess the pollution of honey by heavy metals based on the efforts of an urbanization gradient in the city of Annaba (Northeast Algeria) where the dosage of five heavy metals (Fe, Cr, Ni, Cu, Cd) was carried out in four sites.The level of heavy metals was determined by atomic absorption spectrophotometer. The results obtained indicated that even when all the samples were contaminated they were of good quality since the concentrations did not exceed the international standards.According to the results of heavy metal concentrations in the honeys studied, the most abundant element is Fe with an average concentration of 6.956 ± 2.045 (mg/kg), Cr 0.765 ± 0.197 (mg/kg), Ni 0.6005 ± 0.159 (mg/kg), Cu 0.21025 ± 0.065 (mg/kg) and Cd 0.01425 ± 0.005 (mg/kg).The heavy metals studied are present in all samples but trace amounts. Moreover, the comparison of the honey from the four sites indicates to us that the healthiest honey is that of the urban site.
显示更多 [+] 显示较少 [-]Monitoring of Trihalomethanes and its Cancer Risk Assessment in Drinking Water of Delhi City, India 全文
2022
Mazhar, Mohd. Aamir | Ahmed, Sirajuddin | Husain, Azhar | Uddin, Rahis
The current study determines the concentrations of trihalomethanes (THMs), and the cancer risk associated with them. The tap water sampling was done from the command area of nine water treatment plants (WTPs) of Delhi, India. THMs levels in the water samples from eighteen distribution points were investigated for one year. The cancer risk (CR) related to THMs by different exposure routes i.e., ingestion, dermal absorption, and inhalation, was assessed for males and females. The THM levels varied between 11.41 µg/L to 175.54 µg/L in the distribution system, having a mean level of 77.58 µg/L. The average concentrations of THMs exceeded the maximum permissible limit given by Indian Standards. The concentration of chloroform was maximum, followed by bromodichloromethane, dibromochloromethane, and bromoform. For males and females, the mean value of total CR was 5.09E-05 5.70E-05, respectively. As the THMs levels were high, the total CR value was also more than the negligible level of risk i.e., 1.0 x 10-6 through all exposure routes.
显示更多 [+] 显示较少 [-]Review on the use of Microalgae Biomass for Bioplastics Synthesis: A Sustainable and Green approach to control Plastic Pollution 全文
2022
Nandal, Meenakshi | Khyalia, pradeep | Ghalawat, Anu | Jugiani, Himani | Kaur, Manpreet | Laura, Jitender
Worldwide there is an immense demand for plastic material that results in “white pollution”. Petrochemical-based plastic is used all over the world which leads to adverse impacts on every sphere of the earth. However, many steps have been taken to control this plastic pollution globally, such as chemical treatments, plastic waste incineration, sanitary landfilling, and 7 R programs. Still, plastic pollution is one of the major international problems. Non-biodegradable plastic would not eradicate from our environment until we have an economically feasible and more biodegradable substitute. In recent years algae, especially microalgae, have got attention worldwide, owing to their various applications. Microalgae is one of the sustainable ways of bioplastic synthesis as during cultivation it also purifies wastewater. This review paper has summarized various species of microalgae used for the synthesis of bioplastic, their cultivation system, and methods for bioplastic production by using microalgae biomass, followed by multiple challenges, solutions, and future prospects.
显示更多 [+] 显示较少 [-]Spatiotemporal variation of particulate matter & risk of exposure in the indoor-outdoor residential environment: a case study from urban city Delhi, India 全文
2022
Yadav, Arun | Ghosh, Chirashree
Humans spend close to 90% of their time within the indoor environment. Deteriorating indoor air quality, especially high PM10, PM2.5 and PM1 is slowly becoming a major concern. A study was carried out, for two years, to characterize the spatiotemporal variation of PM in the indoor-outdoor environment across different residential setups (R1, R2, R3, and MC) in the Delhi region. The study established correlation between monthly variations of Indoor/Outdoor (I/O) ratios and meteorological factors. The results showed Spatio-temporal variation in the average mass concentrations of PM10 recorded peak values during the winter season (avg. 514± 72.15 µg/m3) and minimum concentration was observed during monsoon (avg. 91.41± 22.64 µg/m3) months. Among all the sites, the mixed cluster (MC), a residential cum commercial zone reported the highest particulate matter concentration (avg. 308.10 ±37.23 µg/m3) and while R2 reported the least concentration (avg. 244.9± 27.65 µg/m3) within the indoor environment. The I/O ratios of particulate matter were observed to be highest in January (I/O ratio1.6) and lowest in June month (I/O ratio 0.8). PM10, PM2.5, and PM1 dynamics were found to be critically influenced by meteorological factors, regular household activities, and diverse building designs. The short- or long-term exposure of particulate pollutants (beyond the permissible limits) can increase the probability of acute health effects, so there is an utmost requirement to collect better and systematic information about actual exposure levels experienced in different urban residential environments.
显示更多 [+] 显示较少 [-]Health Risk Assessment of Okadaic Acid and Domoic Acid in Some Edible Bivalves from Hormozgan Province in the North of Persian Gulf 全文
2022
Mohebbi-Nozar, Seyedeh Laili | Moratzavi, Mohammad Seddiq | Seraji, Fereshteh | Bahreini, Parto
The biotoxins can enter the marine food chain, and, accordingly, seafood consumers are also at risk of ingesting toxins from contaminated aquatic animals. Hormozgan Province in the north of Persian Gulf is an area with high industrial and urbanization rising rate. In the present work, the aim was to identify the okadaic acid and domoic acid producers in the coastal waters and to investigate on their accumulated concentrations in edible bivalves in order to assess the consumer’s health risk. Water samples were collected during winter 2018 and summer 2019 from one blank and four stations facing industrial and municipal effluents. Four species of edible bivalves were collected from coastal lines of Hormozgan province, at the lowest tide time. The concentrations of toxins were determined by indirect competitive ELISA method. Pseudonitzschia delicatissima, Nitzschia punges and Nitzschia seriata in the production of domoic acid and Dinophysis caudate, Prorocentrum Lima and Ceratium tripos in the production of okadaic acid were identified. The okadaic acid concentrations ranged from 59.8 ± 2.38 to 121.96 ± 28.25 µg/kg, ranging from 0.85 to 83.59 ± 38.72 for Domoic acid. Among the studied bivalves, Pinctada radiate contained the maximum concentrations of measured toxins. For the first time at Hormozgan Province, the consumption guidelines for domoic and okadaic acid were calculated. The human health risk assessment showed that at present time, the algal consumers from Hormozgan province are not at risk of domoic and okadaic acid toxins.
显示更多 [+] 显示较少 [-]School Indoor Air Pollutants: In Relation to Allergy and Respiratory Symptoms among School Children in Urban Areas 全文
2022
Hashim, Zailina | Mohamad Fadzil, Nur Shahira | Mohd Fuad, Siti Raihan | Shamsudin, Shamsul Bahari | Mohd Isa, Khairul Nizam | Song, Tan Tek | Sieman, Jony | Mohd Elias, Saliza | Hashim, Jamal Hisham
Indoor air pollutants affect children’s health and previous research mostly focuses on respiratory and allergic diseases. However, little is known about the risks among school children in East Malaysia. Therefore, we studied associations between school children’s respiratory and allergic symptoms and indoor air pollutants in schools in Sabah, Malaysia. We randomly enrolled 332 school children (14 years old) from 24 classrooms in 6 secondary schools in Kota Kinabalu, Sabah. Information on personal characteristics, respiratory and allergic symptoms were gathered by using a standard questionnaire. The skin prick test was used to characterize the atopy. In each classroom, the indoor concentrations of particulate matter (PM10 and PM2.5), nitrogen dioxide (NO2), formaldehyde, total volatile organic compounds (TVOC), carbon dioxide (CO2) temperature and relative humidity were monitored. Overall, 11.7% reported doctor-diagnosed asthma, 14.8% wheezing, 17.5% day-time breathlessness, 37.0% breathlessness after exercise, 13.0% breathlessness at night-time, 55.1% rhinitis and 10.8% skin allergic in the last 12 months. Regression analysis showed that the onset of wheezing was common in doctor-diagnosed asthma (OR= 8.29, 95% CI= 3.70-16.10) and with parental asthma/allergy (OR= 2.13, 95% CI= 1.10-4.15), and associated with concentrations of NO2 (OR= 1.03, 95% CI= 1.01-1.21) and CO2 (OR= 1.01, 95% CI= 1.01-1.11). Day-time breathlessness was associated with indoor NO2 (OR=1.02, 95% CI= 1.02-1.35) and TVOC (OR= 1.30, 95% CI= 1.10-1.52). The indoor concentrations of NO2, CO2, TVOC and PM2.5 as well as parental asthma/allergy, and parental smoking were associated with the outcome of respiratory and allergic symptoms.
显示更多 [+] 显示较少 [-]Rapid ecological resilience assessment of urban forest parks: An alternative approach 全文
2022
Darabi, Hassan | Hamedi, Roghaye | Ehsani, Amirhoushang | Kafi, Mohsen
Abstract Rising threats, such as climate change, have thus far resulted in disruptions to ecosystems. Therefore, ecological resilience (eco-resilience) to absorb such distractions and maintain the capacity of ecosystems has been the focal point of numerous studies. In most cases, the characteristics of ecosystems are considered as indicators shaping this type of resilience. In this study, an alternative approach was adopted to examine the performance and outcomes of an ecosystem instead of reflecting on affective factors. Therefore, the resilience index (RI) of an urban forest park was assessed using eco-functional indicators, such as eco-volume (Veco), eco-height (Heco), bio-volume (Vbio), and eco-volume (Veco). At first, the forest park zoning was done. Then, each of the introduced indicators was calculated based on its specific parameters. Finally, the RI of the urban forest park was premeditated. The results showed that each zone with more effective Veco, Heco, and Veco gained a higher score in terms of resilience. The obtained score for RI was thus the function of the current ecological state of each zone. The study conclusions also confirmed that the outputs of the applied framework could embody the main indicators of resilience assessments (viz. thresholds, adaptive capacity, and self-organization). The application of this model on a larger scale required further studies.
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