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Ecological and Health Risk Assessment of Trace Metals in Waters from North-West Zone of Akwa Ibom State, Nigeria
2023
Effiong Jonah, Udeme | Friday Mendie, Cecilia | Greogry Asuquo, Uwemmay
Metals contamination in water is becoming a threat to human health. The studies ecological and health risk assessment of trace metals was conducted in seven water bodies in Akwa Ibom State, between May 2021 and April 2022 (twelve months), to evaluate the levels of trace metals contaminant and suitability of the waters for human consumption. Six trace metals were assessed in the water samples; using atomic absorption spectrophotometer after digestion. Pollution indices such as heavy metal pollution index, comprehensive pollution index, contamination index and health risk assessment for non-carcinogenic were employed. The findings were compared with Nigerian Standard for Drinking Water Quality. The mean concentration of some metals (Pb, Cd, Cr, and Cu) in some stations were exceeded the standard limits, while Fe and Ni exceeded the acceptable limits in all the stations, due to anthropogenic activities. The values for HPI in stations I, II, IV and VII were exceeded the threshold of 100, ranging between 61.4 and 743.5; CPI ranged from 1.05 to 3.72, while Cd ranged from 0.94 to 16.3, indicated that the water bodies are highly contaminated. The CDI and HQ values for Fe, Cd, Cr and Cu exceeded the oral toxicity reference dosage of contaminant and stipulated threshold (1) for HI in some stations both in children and adult, indicated that the water bodies are not suitable for human consumption. The findings call for concern regarding their effects on human health, which could be detrimental to the people drinking from these water.
Mostrar más [+] Menos [-]The content of toxic elements in soil-plant system based on ombrotrophic peat with the copper smelting slag recycling waste
2023
Zolotova, Ekaterina | Kotelnikova, Alla | Ryabinin, Viktor
Mining wastes occupy huge areas around the world, therefore, research aimed at their disposal and reclamation of disturbed territories is very relevant. We studied artificial soil based on neutralized ombrotrophic peat (Histosols Fibric) with different content (5% and 10% by weight) of copper smelting slag recycling waste ("technical sand"): finely dispersed (less than 0.05 mm), mechanically activated material. We analyzed the content of toxic element in peat, underground and aboveground parts of lawn grasses and potatoes. The coefficients of concentration and accumulation of elements were calculated. It was found that the introduction of 5% waste leads to exceeding the maximum permissible concentrations and approximately permissible concentrations (the regulated values for Russia) for zinc, copper, arsenic, antimony, and lead. The molybdenum content exceeds the Soil Quality Guidelines accepted in Canada, for selenium the values are at the limit level. The content of zinc, copper, cobalt, arsenic, molybdenum, antimony is significantly reduced (by 2-3 times) during the growing season. Ecological assessment of agricultural plants grown on artificial soil with 5% of "technical sand" showed that there are no excesses of the maximum permissible levels for any regulated element for potato tubers; a slight excess of arsenic was detected for lawn grasses. We additionally assessed the safety of potato tubers using the maximum permissible concentrations for food and established an excess of cadmium (3.4 times on the peat, with the addition of waste almost unchanged) and zinc (1.6 times on peat, 2.8 times for a peat with 10% waste).
Mostrar más [+] Menos [-]Comparison of IAQ Standards in Healthcare Facilities with the aim of providing acceptable Standards in Iran
2023
Farhadi, Forough | Khakzand, Mehdi | Khanmohammadi, MohammadAli | Barzegar, Zahra
Indoor air quality (IAQ) is a significant concern that affects comfort and health. It is well understood that hospitals are thermal environments in which comfort must be calibrated. This comparative study examined existing international standards of IAQ in Iranian health care facilities. A systematic review of studies on IAQ standards was conducted to test the hypothesis regarding which parameters, and at what level, can have an impact on hospital IAQ: EPA, ASHRAE, LEED, BREEAM, NIOSH, OSHA, WHO, ACGIH, Canadian, and OEL. The inclusion criteria were met by 34 of the 1886 studies that were screened from 2010-2021. The findings of the selected studies were classified into four categories for analysis: monitoring of IAQ according to standards (n=34), IAQ in healthcare facilities (n=1), impact of air pollution on human health (n=9), and interventions to improve IAQ (n=1). Based on these IAQ standards, the acceptable limit for CO2 6300 *10³ µg/m³, for CO 9000 µg/m³, for Formaldehyde 19 µg/m³, for NO2 37 µg/m³, for O3 98 µg/m³, for PM2.5 0.1 µg/m³, for PM10 10 µg/m, and for SO2 31 µg/m³ was suggested. The majority of studies conducted monitoring of pollutants in indoor environments used for homes and schools, with the majority of them relying on WHO IAQ standards. CO, PM, and NO2 concentrations have been the most studied and have the longest track record of research. The acceptable limit for IAQ parameters was proposed.
Mostrar más [+] Menos [-]Removal of Pollutants in Wastewater using Plastic-Based Media Biofiltration: A Meta-Analysis
2023
Muliyadi, Muliyadi | Purwanto, Purwanto | Sumiyati, Sri | Soeprobowati, Tri
The use of plastics as a biofilter medium is an environment-friendly and effective technology for reducing pollutants in liquid waste. The main objective is to analyze the ability of biofilters with plastic media to remove pollutants in wastewater by looking at several parameters. Various types of data were developed and analyzed to answer specific goals set through the search engines EBSCO, Scopus, and ProQuest by examining several parameters, including wastewater source, research scale, research period, temperature, media type, media thickness, and pollutant removal. The obtained data were processed to determine the distribution of the descriptions. Data related to biofiltration using plastic media was obtained from 152 articles, with only 14 articles in the search category. These findings show that all types of plastic media are effective for biofilm attachment and bacterial growth, resulting in a very large removal of pollutants present in liquid waste. Biofilters with plastic media are also known to be able to remove contaminants such as Chemical Oxygen Demand, biological oxygen demand, total organic carbon, nitrogen, phosphorus, ammonia nitrogen, hydrogen sulfide, toluene, ammonia, diethanolami, phenol, total suspended solids, and Escherichia coli. Synthetic wastewater (35.71%) was the most common wastewater source. Research related to biofiltration using plastic as the medium is mostly carried out on a laboratory scale with a total of 64.30% and using units of the day as an indicator of changes in a total of 71.42%, with an average experimental temperature of 29.1 °C.
Mostrar más [+] Menos [-]Heavy Metal Pollution Assessment in Lake Rinconada in the Southern Andes, Peru
2023
Salas Mercado, Dante | Belizario-Quispe, Germán | Horna-Muñoz, Daniel
The study was conducted in Lake Rinconada, a glacial lake affected by artisanal and small-scale gold mining activities in the southern Andes in Peru. The objectives of the study were to investigate the spatial distribution of heavy metals (As, Cu, Hg, Pb and Zn) in water and sediments and to assess the degree of metal pollution and ecological risk using the geoaccumulation and potential ecological risk indexes. The concentrations of As and Hg in sediments from Lake Rinconada exceeded the Canadian sediment quality regulations, whereas the concentrations of As, Hg and Pb in water and sediments from the mining-affected tributary, Lunar de Oro River exceeded the Peruvian and Canadian guidelines for water and sediments quality respectively. According to the geoaccumulation and potential ecological risk indexes, Lake Rinconada is extremely polluted by As and Hg, and the pollution is mostly concentrated in the northern part of the lake, where the mining-affected Lunar de Oro River flows into the lake. Concentrations of Pb are also high in the northern part of the lake, suggesting that the nearby gold mining town is a source of pollution. The results of this study allows to report that Lake Rinconada is completely deteriorated.
Mostrar más [+] Menos [-]Impact of Vehicular Traffic on Single Use Surgical Face Masks as a Source of Environmental Micro-fiber Pollution
2023
Spennemann, Dirk
During the COVID-19 pandemic large numbers of single-use, surgical style face masks were lost or discarded in public spaces, primarily in on public streets and car parking settings. Many of these masks were blown onto the road surfaces where they were subjected to degradation through the tire impact of passing vehicle traffic. As series of field observations as well as experimental simulations show that the three-ply polypropylene mask fabric is subjected to shear forces when compressed between the tire and the road surface. The mechanical action breaks the bonds between the fibers (both spunbonded and meltblown) leading to a continual shedding of microfibers. Wind disperses these into the environment along road sides, while surface water action moves them into stormwater drains and from there into the waterways. As the decay is rapid, municipal agencies only have a short window of time to remove stray face masks from the urban environment if micro-fiber pollution is to be reduced.
Mostrar más [+] Menos [-]Optimization of the Photocatalytic Oxidation Process in Toluene Removal from Air
2023
Khoshpasand, Fatemeh | Nikpay, Ahmad | Keshavarz, Mehrdad
The presence of volatile organic compounds in the indoor environment and their unwanted effects on human health are inevitable. That's why different methods have been proposed to remove them from air. The present study examines using photocatalytic reaction system along with TiO2 particles coated on stainless steel webnet to study direct conversion of toluene using a new design. The study was carried out using UV radiation in a dynamic concentrator system. SEM and XRD analyses were performed to characterize prepared catalysts. Here, the aim was to employ photocatalytic oxidation (PCO) to optimize removal efficiency and elimination capacity using response surface methodology (RSM). To this end, initial concentration and flow rate were selected as independent variables. High removal efficiency and elimination capacity were realized using optimal settings. The findings indicated that PCO process with a new design other than RSM was an option to treat air pollution containing volatile organic compounds.
Mostrar más [+] Menos [-]Impact of Mining Activity on Soils and Plants in the Vicinity of a Zn-Pb Mine (Draa Lasfar, Marrakech - Morocco)
2023
Nassima, Elhaya | Ait Melloul, Abdelaziz | khadija, Flata | Sana, El-Fadeli | Pineau, Alain | Barkouch, Yassir
The pollution generated by metallic trace elements discharged by mines into the environment can become a very worrying source of contamination for soil, water and plants. The characterization of the chemical properties of metals in mine tailings and soils is of crucial importance to assess the risk of their potential mobility and therefore their bioavailability. In this paper, the bioavailability of metallic trace elements in agricultural soils in the vicinity of the Draa Lasfar mine in the northwest of Marrakech city (Morocco) was studied by determining the contents of Cd, Cu, Pb and Zn in soils and in two plants: wheat (main food for the human population) and couch grass (main food for livestock). The results showed that these metals move from agricultural land to plants. They also showed that couch grass seems to strongly absorb and accumulate metallic trace elements present in the soil; it removes considerable amounts of metallic trace elements from the soil with its deeply penetrating root system.
Mostrar más [+] Menos [-]Fractal Description of the Temporal Fluctuation of PM2.5 and PM10 Concentrations and their Cross-correlation at Cotonou Autonomous Port and the “Boulevard de la Marina” area (Benin Republic, West Africa)
2023
Koto N’Gobi, Gabin | Agbazo, Medard | Leode, Augustin
The present study aims to provide baseline information on the temporal characteristics of PM2.5 and PM10 concentration time series variations, mainly on the cross-correlation between PM2.5 and PM10, using the improved mathematical and nonlinear methods. Firstly, the fractal theory such as fractal dimension is used to detect the pollution level in PM2.5 and PM10 time series. Secondly, the Multifractal Detrending Moving-Average Analysis (MFDMA) is used to analyze the multifractal characteristics of PM2.5 and PM10 concentrations. Thirdly, Multifractal Detrending Moving-Average cross-correlation Analysis (MFXDMA) is used to study the cross-correlation between PM2.5 and PM10 concentrations measured from January 1 to December 31, 2020, along the Boulevard de la Marina, one of the major roads in Cotonou. The results have indicated that: (1) PM10 and PM2.5 concentration time series are characterized by a fractal dimension, which can permit to detect the pollution levels and to analyze the differences in emissions sources; (2) there is a significant multifractal structure in the PM2.5 and PM10 concentration data and their fluctuations are long-range correlated, however, the multifractal properties and self-memory characteristics change with the months; (3) generally, the multifractal degree and the complexity of PM10 are much stronger than those of PM2.5. However, they present a similar multifractality degree in some months of the year; (4) except, in February, the cross-correlation between PM2.5 and PM10 time series in the months of the year presents multifractal characteristics with positive persistence; (5) the cross-correlation multifractal features show monthly variation. This paper provides the inter-relationship between air PM2.5 and PM10 time series which may help taking steps in controlling the air quality and management of the Cotonou port area environment.
Mostrar más [+] Menos [-]Ambient Air Quality and Health Impact of Exposure to Outdoor Air Pollution in the Moroccan Population: A Systematic Review
2023
Bouchriti, Youssef | Ait Haddou, Mohamed | Kabbachi, Belkacem | Achbani, Abderrahmane | Cherrat, Zakariae | Rida, Jamila | Sine, Hasnaa | Gougueni, Hicham | Amiha, Rachid | Ezaidi, Sarrah
Evidence of the health impact of air pollution in Morocco is scarce. We aimed to test our hypothesis that exposure to air pollutants has a significant impact on the health of Moroccans. For this systematic review, we searched PubMed, ScienceDirect, LILACS, and ProQuest databases, Google Scholar, and forward and backward citations for studies published between the database inception and August 16, 2022. All studies and reports that measure air quality in Morocco and its health impact were included, without language restrictions. This study is registered on PROSPERO under number CRD42020163948. Studies were selected based on inclusion and exclusion criteria rather than their methods. The data was extracted, coded, and prepared for future examination. After that, descriptive and thematic analyses were carried out. Of 1230 records identified, 31 were eligible, all of which had annual air pollutant concentrations in excess of WHO Air Quality Guidelines. The health impact was demonstrated in five studies. The most studied pathologies were asthma, respiratory and cardiac infections in children under 12 years and adults. In addition to heavy metals, the most investigated pollutants were PM10, O3, SO2, and NOx. The significant association between exposure to air pollutants and health in the Moroccan population has been demonstrated, even if it is not causal. Future research should quantify the health impact of pollution in other Moroccan cities.
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