RESUMEN

The aim of this study is to assess and identify the most suitable geospatial interpolation algorithm for environmental sciences. The research focuses on evaluating six different interpolation methods using annual average PM10 concentrations as a reference dataset. The dataset includes measurements obtained from a target air quality network (scenery 1) and a sub-dataset derived from a partitive clustering technique (scenery 2). By comparing the performance of each interpolation algorithm using various indicators, the study aims to determine the most reliable method. The findings reveal that the kriging method demonstrates the highest performance within environmental sciences, with a spatial similarity of approximately 70% between the two scenery datasets. The performance indicators for the kriging method, including RMSE (root mean square error), MAE (mean absolute error), and MAPE (mean absolute percentage error), are measured at 3.2 µg/m3, 10.2 µg/m3, and 7.3%, respectively.This study addresses the existing gap in scientific knowledge regarding the comparison of geospatial interpolation techniques. The findings provide valuable insights for environmental managers and decision-makers, enabling them to implement effective control and mitigation strategies based on reliable geospatial information and data. In summary, this research evaluates and identifies the most suitable geospatial interpolation algorithm for environmental sciences, with the kriging method emerging as the most reliable option. The study's findings contribute to the advancement of knowledge in the field and offer practical implications for environmental management and planning.

Asunto(s)

RESUMEN

The accumulation of 55 elements in lichens under the heap of a former nickel smelter (village Dolná Streda, Slovakia) and at eight sites at different distances from the heap plus six sites throughout Slovakia was studied to determine the elemental profile. The major metals in the heap sludge and in the lichens below the heap (Ni, Cr, Fe, Mn, and Co) were surprisingly low in lichens from both the near and far vicinity of the heap (4-25 km), indicating limited airborne spread. However, two different sites with metallurgical activity (another site near the ferroalloy producer in Orava) typically contained the highest amount of individual elements, including rare earth elements, Th, U, Ag, Pd, Bi and Be, and their separation from other sites was confirmed by PCA and HCA analyses. In addition, the amounts of Cd, Ba and Re were highest at sites without a clear source of pollution and further monitoring is needed. It was also an unexpected finding that the enrichment factor calculated using UCC values was increased (often considerably >10) for 12 elements at all 15 sites, indicating eventual anthropogenic contamination with P, Zn, B, As, Sb, Cd, Ag, Bi, Pd, Pt, Te and Re (and other EF values were locally increased). Metabolic analyses showed a negative correlation between some metals and metabolites (ascorbic acid, thiols, phenols and allantoin), but slightly positive (amino acids) or highly positive correlation with purine derivatives hypoxanthine and xanthine. The data suggest that lichens adapt their metabolism to excessive metal loading and that epiphytic lichens are suitable for identifying metal contamination even at apparently clean sites.

Asunto(s)

RESUMEN

BACKGROUND: Asthma is a common pediatric chronic respiratory disease worldwide. Previous studies showed the prevalence of childhood asthma increased in developed countries as well as in Taiwan in the late 20th century. Recently, several reports from different parts of the world showed a reversed trend in this epidemic of childhood asthma prevalence. This study investigated the trend of childhood asthma through serial cross-section questionnaire surveys in the southern part of Taiwan, and identified associated factors related to this trend in elementary school children. METHODS: We used the Chinese version of the International Study of Asthma and Allergies in Childhood (ISAAC)29 questionnaire to assess the asthma status of elementary school students aged 6-12 years in Tainan city in 3 independent study periods, namely, 2008-2009, 2010-2012, and 2017-2018. We assessed the trend of "asthma" and "related respiratory symptoms" across 3 study periods. RESULTS: Of the 19,633 respondents, 17,545 (89.4%) completed the questionnaires. After adjustment for covariates, the prevalence of asthma and related respiratory symptoms was significantly lower in 2017-2018 than in the 2 earlier periods. Among the protective factors, the increasing rate of breastfeeding might be partly responsible for the observed reduced prevalence of current asthma and exercise-induced wheeze, but not physician-diagnosed asthma. The presence of pets in the house was the risk factor that correlated with the prevalence of nocturnal cough. Pearson correlation analysis showed a significant correlation of the prevalence of physician-diagnosed asthma, current asthma, and exercise-induced wheezing with the concentrations of air pollutant particles with aerodynamic diameter ≤10 µM (PM10) (r = 0.84, 0.77 and 0.81, respectively). CONCLUSION: The prevalence of asthma and related respiratory symptoms has declined in elementary school-age children in southern Taiwan. The increased prevalence of breastfeeding, decreased rate of the presence of pets in the house, and improvement in outdoor air pollution seem to be related to this decreasing trend of asthma in school children. Our findings will provide the scientific base to empower prevention policy to reverse the trend of childhood asthma prevalence. TRIAL REGISTRATION: N/A.

RESUMEN

Platinum group elements (PGEs, i.e. platinum, Pt; palladium, Pd; and rhodium, Rh) catalyse over 90% of carbon monoxide, nitrogen oxides and hydrocarbons from combustion residues into water vapour, carbon dioxide and nitrogen in the vehicle's catalytic converter. But there is a major concern over these metals in the scientific world, since they are emitted by catalytic converters and accumulating in the environment. The distribution of PGEs in PM10 fraction was studied in an open urban site (Nantes, France) and in a tunnel (Paris, France) using low- and high-volume air samplers. PGEs were also investigated in dry deposition particles and deposited dust sampled in the tunnel. Pd occurred at the highest levels in both PM10 and dry deposition samples, followed by Rh and Pt. Maximum concentrations in PM10 fraction were 114 pg m-3 for Pd, 14.3 pg m-3 for Rh and 3.3 pg m-3 for Pt in the urban site (Nantes) and 91 pg m-3 for Pd and 16 pg m-3 for Rh in the tunnel (Paris). The concentrations for dry depositions in the tunnel were 261 µg kg-1 for Pt, 431 µg kg-1 for Pd and 85 µg kg-1 for Rh. The results on PGEs levels in atmospheric particles and dry depositions are the first data of their kind in France and will provide new insights into the contribution of catalytic converters to the environment. We also observed Pd and Rh being 2 times higher PM10 particles compared to dry depositions, leading us to suggest that particles rich in Pd and Rh are smaller than 10 µm. An overall concentration trend of Pd > Rh > Pt was observed in all samples, showing the replacement of Pt by Pd and Rh in newer catalytic converters.

RESUMEN

This work aims to provide a methodology framework which allows to improve the performance and efficiency of an air quality monitoring network (AQMN). It requires to be constituted by a minimum and reliable number of measurement sites. Nevertheless, the AQMN efficiency should be assessed over time, as a consequence of the possible emergence of new emission sources of air pollutants, which could lead to variations on their spatial distribution within the target area. PM10 particles data monitored by the Community of Madrid's (Spain) AQMN between 2008 and 2017 were used to develop a methodology to optimize the AQMN performance. The annual spatial distribution of average PM10 levels over the studied period monitored by all current stations vs those more representative was provided by a geographic information system (GIS), and the percentage of similarity between both postulates was quantified using simple linear regression (> 95%). As one innovative tool of this study, the practical application of the proposed methodology was validated using PM10 particles data measured by AQMN during 2007 and 2018, reaching a similitude degree higher than 95%. The influence of temporal variation on the proposed methodological framework was around 20%. The proposed methodology sets criteria for identifying non-redundant stations within AQMN, it is also able to appropriately assess the representativeness of fixed monitoring sites within an AQMN and it complements the guidelines set by European legislation on air pollutants monitoring at fixed stations, which could help to tackle efforts to improve the air quality management.

Asunto(s)

RESUMEN

Background: Quantification of the attributed effects of air pollution determines the impact of air pollutants on the community and shows the critical condition of air quality. This study aimed to quantify and estimate the cardiovascular and respiratory diseases attributed to PM10 in Urmia during 2011-2016. Methods: In this descriptive-analytic study, at first, hourly data of pollutant PM10 concentrations were received from air pollutants station located in the Department of Environmental Protection. The data were evaluated using AirQ2.2.3 software after primary and secondary processes and filtering. Results: The results showed that the mean annual concentration of PM10 during 2011-2016 was 88.66, 92.45, 81.22, 78.38, 113.78, and 92.67 µg /m3, respectively. The number of hospitalized cases due to respiratory diseases attributed to PM10 in this period was 486, 525, 459, 453, 684, and 552, respectively, and the number of cases due to cardiovascular diseases was 188, 203, 177, 175, 263, and 213, respectively. Conclusion: Considering the attributed health effects of PM10, the necessary measures should be taken to identify the causative agents and to understand the mechanisms of these processes and correct them.

RESUMEN

This research article investigates the particulate matter originated from the exhaust emissions of 20 bus models, within the territory of Vladivostok, Russian Federation. The majority of evaluated buses (17 out of 20) had emissions of large particles with sizes greater than 400 µm, which account for more than 80% of all measured particles. The analysis of the elemental composition showed that the exhaust emissions contained Al, Cd, Cu, Fe, Mg, Ni, Pb, and Zn, with the concentration of Zn prevailing in all samples by two to three orders of magnitude higher than the concentrations of the other elements.

RESUMEN

Despite the fact that environmental pollution due to motorcycle exhaust gases reports a great increase, motorcycle production exhibits a great increase through the last years. Countries of Asia and Africa are reported to be the major regions where two-wheeled vehicles are a major transportation mode, with tens of millions of units sold per year. Motorcycle exhaust particles are considered to be the major contributor to environmental pollution due to their airborne dispersion, containing great amount of polycyclic aromatic hydrocarbons (PAHs). This study aims at reporting an objective analysis of the main sources of the ambient air pollution as also particle size distribution and chemical composition analysis of particulate matter originated from the exhausts of two-wheeled vehicles used in the territory of Vladivostok, Russia. Various types of two-wheeled vehicles were examined (motorcycles, ATVs, scooters and wet bikes) using different types of engine and fuel system. Experimental results showed that there was no clear relation to the particle size distribution with the engine displacement of motorcycle and the number of strokes and the fuel system. Instead, there were reported two clear assumptions. The first one is that regarding to the motorcycle brand, a few samples did not exhibit a great percentage of PM10 fraction. The second one is that more modern vehicles, that have a harmful gas afterburning system, are usually the source of an increased percentage of PM10 emitted particles. At last, it should be mentioned that the laser particle size analysis method is capable of determining the particle sizes after their agglomeration whereas the optical morphometry method allows to determine the real particle size of emissions. In conclusion, it can be pointed out that the agglomeration of particles can lead to the reduction in the toxicity of particles emissions originated from two wheeled-vehicles.