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Spatial distribution, sources, and risk assessment of major ions ad trace elements in rainwater at Puchuncaví Valley, Chile: The impact of industrial activities
2020
Cereceda-Balic, Francisco | Gala-Morales, María de la | Palomo-Marín, Rosario | Fadic, Ximena | Vidal, Victor | Funes, Mario | Rueda-Holgado, Fernando | Pinilla-Gil, Eduardo
This article presents the results of a study on the chemical composition of rainwater as an environmental pollution factor in the surroundings of the Puchuncaví - Ventanas industrial complex (V Region, Chile), with the main objectives of assessing acidification and neutralisation factors, measuring elemental pollutant levels including calculation of enrichment factors and pollution sources assignment, and assessing the risk derived from elemental pollutant loads in rainwater, both for human use and natural ecosystems. Forty-seven weekly rainwater samples were collected during the winter (May–August) 2010 (24 samples) and 2011 (23 samples) at three sampling location with different degree of impact from the main emission sources. The pH, conductivity and major ions were analyzed by ion chromatography, as well as 18 traces and main elements by ICP-MS. Most rainwater samples had pH below 5.6, indicating the risk of acidification, but neutralisation factors, mainly by Na⁺ and NH⁴⁺ were also noticed. The elements emitted by anthropogenic activities had significant enrichment values in the rainwater of the area studied, and the principal component analysis (PCA) identified four sources related to the metallurgical industry – crustal material, marine material, traffic -industry and industrial activities. The risk assessment showed that As content in rainwater is above the WHO guideline value for drinking water at some points in the study area. The contribution of Pb and Cd in rainwater to the soil critical loads turned out to be relatively low, with a maximum of 22.1% for Pb in the vicinity of the industrial complex.
Mostrar más [+] Menos [-]Contribution of locally-produced and transported air pollution to particulate matter in a small insular coastal city
2020
Triantafyllou, E. | Diapouli, E. | Korras-Carraca, Μ.Β | Manousakas, M. | Psanis, C. | Floutsi, A.A. | Spyrou, C. | Eleftheriadis, K. | Biskos, G.
The concentrations, size distributions, and elemental compositions of atmospheric aerosol particles over a small but representative (in terms of size, population, and geographical characteristics) insular coastal city in the North Aegean Sea were measured during winter and summer. Mean PM₂.₀ and PM₁.₀ concentrations at the city centre were respectively 26 and 21 μg m⁻³ during the cold period, and 21 and 15 μg m⁻³ during the warm period. Although these concentrations are considerably lower compared to corresponding values of PM₂.₅ and PM₁.₀ recorded in large cities in the region, they are still very close to the mean annual standards set by the EU for PM₂.₅. Higher average mass concentrations (by ca. 26–36% for Total Suspended Particles, PM₂.₀ and PM₁.₀) were observed in the cold period compared to those in the warm period due to the additional emissions from domestic heating and the weaker atmospheric dilution. The elemental composition measurements showed that crustal and anthropogenic elements (i.e., K, Ca, Ti, Mg, Fe, As, S) in the collected particle samples were also enriched when polluted air masses were transported from Northeastern Turkey. These measurements also showed that natural sources contribute sea-salt and re-suspended soil to the particulate matter load in the city's atmosphere. Non-exhaust traffic emission sources were also found to be an important contributor, as indicated by the good correlations (R² = 0.40–0.91) between crustal and traffic-related elements (i.e., Zn, Cr, Cu, and Mn). Overall, PM measurements in the urban environment in the region are relatively high, being influenced by both local sources and long-transported air masses.
Mostrar más [+] Menos [-]Seasonal effects of atmospheric particulate matter on performance of different types of photovoltaic modules in sanliurfa, Turkey
2020
Dogan, Tuba Rastgeldi | Beşli, Nurettin | Aktacir, Mehmet Azmi | Dinç, Merve Nur | İlkhan, Mehmet Akif | Öztürk, Fatma | Yıldız, Melek
In Turkey, Southeastern Anatolia region is the highest in terms of solar radiation level. However, the provinces in the region are subject to Particulate Matter (PM) coming from the Sahara desert, the Syrian Desert and the Arabian Desert by atmospheric transport. The daily limit of PM₁₀ and PM₂.₅ set by WHO for health is often exceeded in Sanliurfa. PM₁₀ and PM₂.₅ pollutants also accumulate on the Photovoltaic (PV) panels and cause loss of PV panel performance. In this study, the effects of atmospheric dust deposition on the performance of PV panel was determined for both monocrystalline and polycrystalline technologies under Sanliurfa atmospheric conditions. Two panels with the same characteristics were used for each PV panel group from 2 different PV technologies. One of the panels in the group was cleaned by washing with distilled water every Monday while the other was not cleaned. Thus, the effect of the dust accumulation on the PV panel was determined by comparison to the cleaned PV panel. PV panel power is measured with I–V meter. Panel surface temperature, solar radiation and other meteorological parameters are measured simultaneously. The measurements were done every Monday, Wednesday and Friday at 12:00 am from May 1 to December 31, 2019. It is observed that the dust accumulation reduces the PV power output up to 8% depending on the amount of radiation. During the summer months, the power loss on the average is 4.33% for monocrystalline and 4.57% for polycrystalline. In the autumn months, it is less than 1.77%.
Mostrar más [+] Menos [-]Carbon isotope compositions and TC/OC/EC levels in atmospheric PM10 from Lower Silesia (SW Poland): Spatial variations, seasonality, sources and implications
2020
Górka, Maciej | Kosztowniak, Elżbieta | Lewandowska, Anita U. | Widory, David
PM₁₀ samples were collected at eight monitoring (urban, industrial and regional background) stations during 2011 in SW Poland (Voivodeship of Lower Silesia) with the objectives of identifying their potential sources, as well as of quantitatively estimating the anthropogenic impact on their carbon content by coupling carbon stable isotope compositions of the total carbon (TC) with organic (OC) and elemental carbon (EC) concentrations. Results showed that (i) the highest OC and EC concentrations measured at the five urban background stations were 11.9 and 1.9 μg m⁻³, respectively, with an average δ¹³CTC of −26.5 ± 1.13‰. Annual average concentrations measured (ii) at the industrial and (iii) the two regional stations were similar for OC (6.9 and 6.4 μg m⁻³, respectively) and EC (0.9 and 0.8 μg m⁻³, respectively) with average δ¹³CTC of −27.4 ± 0.81 and −27.6 ± 0.99‰, respectively. This indicates that similar contamination sources explain the PM₁₀ levels at stations (ii) and (iii), however significantly different from the source(s) influencing station (i). Moreover, using an isotope mass balance that incorporates δ¹³CTC and OC and EC concentrations, we show that while during the heating season coal is the dominant source of aerosol contamination (with contributions ranging from 5.1 to 73.8 μg m⁻³), during the vegetative season road traffic is the dominant one (with contributions ranging from 2.2 to 20.2 μg m⁻³). These large ranges confirm the spatiotemporal heterogeneity of air contamination, even within such a small monitoring area, and should be taken into consideration for future implementation of air quality management measures at larger, e.g. national and international, scales.
Mostrar más [+] Menos [-]Ionic composition of PM2.5 particle fraction at a coastal urban background site in Croatia
2020
Gluščić, Valentina | Čačković, Mirjana | Pehnec, Gordana | Bešlić, Ivan
The mass concentrations and content of water-soluble anions (Cl⁻, NO₃⁻, SO₄²⁻) and cations (Na⁺, NH₄⁺, K⁺, Mg²⁺, Ca²⁺) in the PM₂.₅ particle fraction were measured, and an investigation of their relationship and their contribution to the total PM₂.₅ mass measured was conducted at an urban background site as part of the Croatian monitoring network for air quality located in Rijeka, Croatia. Daily samples of PM₂.₅ particle fraction were collected over 2017 on PTFE filters using a low volume sampler Sven Leckel SEQ 47/50. Mass concentrations of the PM₂.₅ particle fraction were determined by gravimetry according to the standard HRN EN 12341:2014 (EN 12341:2014). The content of water-soluble inorganic anions and cations were determined using a Thermo Scientific ICS-5000 capillary ion chromatograph. Results show that the annual average PM₂.₅ mass concentration was 9.65 μg m⁻³ and did not exceed the limit value of 25 μg m⁻³ given by the Regulation on the level of pollutants in air (OG No. 117/12). The annual average mass concentrations of ions in PM₂.₅ particle fraction was SO₄²⁻> NH₄⁺> NO₃⁻ > Ca²⁺> K⁺> Na⁺> Cl⁻ > Mg²⁺. The contributions of total anion mass and total cation mass to the total PM₂.₅ mass were 25.4% and 12.8%, respectively. The acidic property of PM₂.₅ was obtained in spring and winter and slightly acidic in summer and autumn. For a prediction of the pollutant sources, we ran a factor analysis which was performed using the statistical packages STATISTICA 13.0. After varimax rotation, the obtained four principal component factors were found to account for 86% of the variance. Factor loadings > 0.7 were considered significant.
Mostrar más [+] Menos [-]Contents, distribution and sources of lanthanoid elements in rural and urban atmospheric particles in Cienfuegos (Cuba)
2020
Morera-Gómez, Yasser | Alonso-Hernández, Carlos Manuel | Widory, David | Lasheras, Esther | Santamaría, Jesús Miguel | Elustondo, David
This study investigates the contents, distribution patterns, and sources of lanthanoid elements (La to Lu) in aerosols with an aerodynamic diameter ≤10 μm (PM₁₀) in a coastal Caribbean region in order to better constrain the origin of the atmospheric PM contamination. We sampled and analysed PM₁₀ aerosols during 2015 simultaneously at a rural and an urban site in Cienfuegos (Cuba) as well as particles samples from regional contamination sources. Results showed that the sum of the studied lanthanoids concentrations ranged from 0.03 to 13.42 ng m⁻³ and from 0.51 to 18.75 ng m⁻³ at the rural and the urban site, respectively. Time variations for the lanthanoid concentrations displayed similar trends and showed that the highest concentrations corresponded to the influence of the African dust for both sites, but presented distinct variability and lower concentrations when dust intrusions were less frequent. The lanthanoid distribution patterns in the rural and urban sites were significantly different, due to the impact of different local combustion sources. Our results were comforted by comparing the degree of fractionation of the lighter and heavier lanthanoids and the δEu and δCe anomalies between our PM₁₀ samples and those of the local sources of contamination. Ultimately, we highlight the added value of lanthanoid elements as reliable indicators for discriminating emission sources and for tracking the origin of atmospheric particulate matter.
Mostrar más [+] Menos [-]Differences in isoprene and monoterpene emissions from cold-tolerant eucalypt species grown in the UK
2020
Purser, Gemma | Heal, Mathew R. | White, Stella | Morison, James I.L. | Drewer, Julia
The UK may be required to expand its bioenergy production in order to make a significant contribution towards the delivery of its ‘net zero’ greenhouse gas emissions target by 2050. However, some trees grown for bioenergy are emitters of volatile organic compounds (VOCs), including isoprene and terpenes, precursors in the formation of tropospheric ozone, an atmospheric pollutant, which require assessment to understand any consequent impacts on air quality. In this initial scoping study, VOC emission rates were quantified under UK climate conditions for the first time from four species of eucalypts suitable for growing as short-rotation forest for bioenergy. An additional previously characterised eucalypt species was included for comparison. Measurements were undertaken using a dynamic chamber sampling system on 2-3 year-old trees grown under ambient conditions. Average emission rates for isoprene, normalised to 30 °C and 1000 μmol m⁻² s⁻¹ PAR, ranged between 1.3 μg C gdw⁻¹ h⁻¹ to 10 μg C gdw⁻¹ h⁻¹. All the eucalypt species measured were categorised as ‘medium’ isoprene emitters (1–10 μg C gdw⁻¹ h⁻¹). Total normalised monoterpene emission rates were of similar order of magnitude to isoprene or approximately one order of magnitude lower. The composition of the monoterpene emissions differed between the species and major compounds included eucalyptol, α-pinene, limonene and β-cis-ocimene. The emission rates presented here contribute the first data for further studies to quantify the potential impact on UK atmospheric composition, if there were widespread planting of eucalypts in the UK for bioenergy purposes.
Mostrar más [+] Menos [-]Evaluation of hourly-based precipitation chemistry in suburban site of Bolu
2020
Karadeniz, Hatice | Yenisoy-Karakaş, Serpil
Precipitation chemistry is important for understanding atmospheric chemistry and transportation mechanism for a region. Therefore, 6-h rain samples were collected manually on the Black Sea Region of Turkey between March 2019 and May 2019. Totally, 21 wet deposition samples were collected in 12 rainy days. The collected rain samples were analyzed by ion chromatography for ions, including Cl⁻, NO₂⁻, NO₃⁻, SO₄²⁻, Na⁺, Ca²⁺, Mg²⁺, K⁺, NH₄⁺. Volume weighted mean (VWM) concentrations of ions were calculated and were in the order of Na⁺ > Ca²⁺ > Cl⁻ > SO₄²⁻ > NO₃⁻ > Mg²⁺ > K⁺ > NH₄⁺> NO₂⁻. The pH values of individual precipitation varied from 4.70 to 8.07. Anion to cation ratio was 0.74 ± 0.34 thus it was an indication of anion deficiency. A strong correlation between NH₄⁺ and SO₄²⁻, NH₄⁺ and NO₃⁻, Ca²⁺ and SO₄²⁻, Ca²⁺, and NO₃⁻ was found in the samples due to the neutralization process. The back trajectory model was used to find the long-range sources and the influence of air masses coming from Saharan, Europe, and the Black Sea. Calcium ion was found to be an effective ion in the neutralization processes by analysis of multiple linear regression and neutralization factor calculation. Approximately 79.5% of SO₄²⁻ and 59.7% of NO₃⁻ were neutralized by Ca²⁺ and NH₄⁺. The washout mechanism for Na⁺, Mg²⁺, Ca²⁺, and K⁺ was dominantly observed on the March 12, 2019. Rainout mechanism was seen on the April 13, 2019 rain event due to the long-range transportation from Saharan Dust.
Mostrar más [+] Menos [-]Distribution, characterization and health risk assessment of size fractionated bioaerosols at an open landfill site in Dehradun, India
2020
Madhwal, Sandeep | Prabhu, Vignesh | Sundriyal, Sangeeta | Shridhar, Vijay
Open landfilling is a common practice of waste dumping in developing countries, generating a range of environmental and public health hazards. In this study, we determined the distribution, composition and exposure risk of the size-segregated fungal and bacterial bioaerosols in an open landfill site in Dehradun, India. Bioaerosol and particulate matter (PM) measurements were carried out using a six-stage viable Andersen Cascade Impactor and a Wide Range Aerosol Spectrometer, respectively. Pearson correlation analysis was used to determine the relation of bioaerosol concentration with meteorological parameters and PM. The mean concentration of fungal and bacterial aerosols was observed to be 4582.75 ± 1358.25 CFU/m3 and 3609.53 ± 1000.28 CFU/m3, respectively. The bioaerosol composition showed the predominance of potential pathogens including Aspergillus (25.42%), Penicillium (20.34%), Cladosporium (15.25%), Alternaria (13.56%); and gram-negative Bacillus (21.15%), Streptobacillus (17.31%), Coccus (13.46%). Also, an inhalation risk assessment was conducted for the age-specific predictions of bioaerosol and PM deposition in human airways using a multiple path particle dosimetry model. For bioaerosols, maximum submicron depositions in the pulmonary region were observed in adults, while for PM, in children and infants. Finally, to identify the bioaerosol exposure caused respiratory disorders, a questionnaire-based health survey was conducted among the exposed population around the landfill site. The chi-square test showed significantly higher respiratory complaints in females for cold, cough, chest pain and chest tightness than in males. This work highlights the role of bioaerosols and PM in human health disorders in occupational environments associated with waste management.
Mostrar más [+] Menos [-]Modeling urban background air pollution in Quito, Ecuador
2020
Valencia, Victor H. | Hertel, Ole | Ketzel, Matthias | Levin, Gregor
This study estimates air pollution at urban background level for Quito, Ecuador, using the Urban Background Model (UBM) developed at Aarhus University, Denmark. Hourly concentrations of CO, NO₂, NOₓ, O₃, PM₂.₅ and SO₂ were calculated for the year 2009. UBM performance is evaluated at six monitoring locations. The air pollution emission inventory was scaled, using calibration factors, until modeled concentrations were in line with observations. Predicted values were graphically and statistically evaluated by comparison to measurements. The statistical assessment is conducted for: Fraction of predictions within a factor of two of the observations (FAC2), Fractional mean bias (FB), Normalized mean-square error (NMSE) and Normalized absolute difference (NAD). Results show that the UBM model successfully predicts concentrations of CO, NO₂, NOₓ, O₃ and PM₂.₅ while the predicted SO₂ concentrations are unsatisfactory. PM₂.₅ modeling meets the criteria of acceptance, but their results depend largely on the regional levels, so the quality of this information is extremely relevant. The UBM model was applied for the years 2008 and 2010 using meteorological data retrieved from the modeling sites with emissions and calibration factors derived for the year 2009, showing a performance similar to that of 2009. The findings confirm the applicability of UBM to predict air pollution at the urban background level in Quito. Satisfactory results are obtained by applying meteorological data derived from any of the available monitoring stations. The unsatisfactory results for SO₂ suggest that emission data should be reviewed and that this cannot be obtained simply by scaling.
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