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Monitoring of Trihalomethanes and its Cancer Risk Assessment in Drinking Water of Delhi City, India Full text
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.
Show more [+] Less [-]Review on the use of Microalgae Biomass for Bioplastics Synthesis: A Sustainable and Green approach to control Plastic Pollution Full text
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.
Show more [+] Less [-]Spatiotemporal variation of particulate matter & risk of exposure in the indoor-outdoor residential environment: a case study from urban city Delhi, India Full text
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.
Show more [+] Less [-]Health Risk Assessment of Okadaic Acid and Domoic Acid in Some Edible Bivalves from Hormozgan Province in the North of Persian Gulf Full text
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.
Show more [+] Less [-]School Indoor Air Pollutants: In Relation to Allergy and Respiratory Symptoms among School Children in Urban Areas Full text
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.
Show more [+] Less [-]Rapid ecological resilience assessment of urban forest parks: An alternative approach Full text
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.
Show more [+] Less [-]A Comparative Study on Air Quality Measurement and Spatial Distribution of Pollutants in Pars Special Economic Energy Zone (PSEEZ) Full text
2022
Hassani Ziabari, Seyed Ebrahim | Tabatabaei, Tayebeh | Amiri, Fazel | Ramavandi, Bahman
Pars special economic energy zone (PSEEZ) in Iran is the second largest energy zone in the world with more than 60,000 operational and non-operational personnel. Considering the nature of the activities being done in PSEEZ, it is rational to expect that a wide range of hazardous materials be present in the air composition of this area. It is shown in this research that Benzene-Toluene-Ethylbenzene-Xylene (BTEX) are the most challenging in PSEEZ and benzene concentration violates the standards in all sampling points. The study area is divided into three subzones of gas refineries, petrochemical complexes and non-operational areas. In the gas refineries, benzene concentration is recorded to be 480 times higher than the standard for exposure limit. The concentration of benzene in petrochemical complexes is also about 160 times higher than the standard limit. Considering the vicinity of the petrochemical complexes the cumulative impacts of BTEX will also worsen the situation regarding BTEX cancer risk. In non-operational areas, benzene concentration reaches 40 times higher than the standard limit which is a serious health challenge. Comparing the data of BTEX distribution with AQI proves that AQI solely is not an appropriate index for assessing the air quality in PSEEZ and defining local indices for air quality assessment with taking hazardous chemicals such as BTEX into account. Moreover, some other pollutants such as heavy metals and H2S are detected in the air quality in significant amounts which raise the need to a reconsideration in location of unprotected non-operational personnel.
Show more [+] Less [-]Reviewing of using Nanomaterials for Wastewater Treatment Full text
2022
Abdulkhaleq Alalwan, Hayder | Alminshid, Alaa | Mustafa Mohammed, Malik | Mohammed, Mohammed | Hatem Shadhar, Mohanad
Increasing the pollution rate of water sources is one of the most severe issues that the world faces. This issue has stimulated researchers to investigate different treatment methods such as adsorption, chemical precipitation, membrane filtration, flocculation, ion exchange, flotation, and electrochemical methods. Among them, adsorption has gained broad interest due to its ease of operation, low cost, and high efficiency. The critical factor of the successful adsorption treatment process is finding attractive adsorbents with attractive criteria such as low cost and high adsorption capacity. In the last few decades, nanotechnology has attracted much attention, and numerous nanomaterials have been synthesized for water and wastewater treatment. This work provides a quick overview of nanomaterials, which have been investigated for water remediation as adsorbent and photocatalyst. This work reviewed more than 100 articles to provide a critical review that would determine the limitation of using nanomaterials in water treatment at the commercial scale.
Show more [+] Less [-]Arbuscular mycorrhizal fungi prevent mercury toxicity in Lactuca sativa (L.) seed germination Full text
2022
Escobar-Vargas, Sebastián | Vargas Aguirre, Carlos | Rivera Páez, Fredy
Mercury pollution is an issue of global concern. In Colombia, the use of contaminated water for food crop irrigation and artisanal mining contributes to mercury pollution in soil, affecting food production and restoration of disturbed areas. Mycorrhizal fungi are symbionts that provide benefits to plants including resistance to heavy metals, but fungal effects on germination remain to be fully described. This study tested the effect of mercury and mycorrhizal fungi on Lactuca sativa seed germination. A 2x5 completely randomized factorial experiment was developed to assess the effect of five HgCl2 polluted treatments, two mycorrhizal treatments (i.e., with inoculum, without inoculum), and the interaction of both factors on seed germination, seedling root colonization, pH, and final water content. In samples with no mercury pollution, mycorrhizal fungi had an inhibitory effect on seed germination. Likewise, the effect of mercury on seed germination is significantly inhibitory. However, pots inoculated with arbuscular mycorrhizal fungi showed constant germination probabilities, independently of mercury concentration. According to the best model determined for the data, a key step in the mitigation of mercury toxicity in seed germination is to prevent substrate pH changes. The environmental conditions of the experiment contributed to densely activate populated biomass of inoculum, which promoted root invasion from various points. Overall, the presence of mycorrhizal fungi in seedbeds could lead to a reduced number of plant individuals. However, the use of fungal inoculum in polluted environments, highly contributes to plant establishment, which is relevant in further vegetable cultivations growing in soil polluted areas.
Show more [+] Less [-]Characterization and Application of Biochar from spent fermentation sludge of coir wastes in removing Malachite green from effluent water Full text
2022
Sudhakaran, Ajith | Rajan, Revathy | Ravindranath, Anita
Lignin rich solid residues after saccharification during the production of ethanol from lignocellulosic substrates are major concern during past times. These solid residues left after the saccharification of Coir pith and Bit fiber waste are pyrolysed at 350 oC to yield biochar, which has been characterized and its potential for removal of Malachite Green, a dye present in the effluents from coir product manufacturing units are studied. FTIR and XRD spectra revealed the diverse functional groups present on the surface of biochar. SEM images showed the porous structure of the biochar. A maximum dye removal efficiency of 99.5% was achieved using Coir Pith Biochar (1 %) within 24 hours of treatment at a dye concentration of 100 mg/l. The removal efficiency was 99.4 % using Bit Fiber Biochar (0.8 %) in the same treatment period. The efficiency of removal was enhanced on adjusting the pH to 4 at which the dye removal of 99.6 % and 99.7 % was achieved using Bit fiber biochar and Coir pith biochar respectively. The residence time was significantly reduced to 2 and 4 hours respectively for bit fiber and coir pith biochar at pH 4 and hence the produced biochars are cost effective adsorbents for removal of dyeing effluents in wastewater. The adsorption fits into pseudo-second order kinetics and is well described by langmuir isotherm model. This would also facilitate the sustainable use of spent solid substrates left after lignocellulosic ethanol production in a more economical way.
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