Elucidating Best Geospatial Estimation Method Applied to Environmental Sciences.

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.

Influence of the products of biomass combustion processes on air quality and cancer risk assessment in rural environmental (Spain).

Polycyclic aromatic hydrocarbons (PAHs) associated with atmospheric particles represent a significant risk to human health. This issue is even more relevant in environments where biomass combustion processes are considered as the major potential emission sources, such as the rural ecosystem. This study aimed to assess the levels of PM10-bound PAHs in several rural locations, their distribution along a year and how weather variables could influence them. Also, we focused on the emission sources and the comparison of the PAH mixtures to assess similitude among the sampling points. PM10-bound PAHs levels were monitored at three rural locations (north, center, and south) of Spain between April 2017 and February 2018. The study revealed that there were substantial differences regarding the levels of ΣPAHs, being higher in the central zone (IS; 65.4 mg/m3), then in the south (VA; 35.8 ng/m3) and finally in the north (NA; 20.9 ng/m3). IS and VA showed a similar distribution of emission sources, and temperature and wind speed seemed to influence negatively over the levels of PAHs likely. At both locations, PAH levels ran parallel throughout the year, with maximum levels during cold seasons and a greater presence of high molecular weight PAHs; however, the levels of PAHs and the most representative PAHs differed. On the other hand, NA was characterized for having another distribution of emission sources, which determined other representative PAHs, higher levels during spring, and a similar presence of high/medium/low molecular weight. Finally, the levels of ambient air PAHs represented an acceptable risk to people.

An optimized approach for estimating benzene in ambient air within an air quality monitoring network.

Benzene is a carcinogenic air pollutant for which European legislation has set an annual limit and criteria for the number of fixed monitoring sites within air quality networks (AQMN). However, due to the limited number of fixed sites for benzene measurement, exposure data are lacking. Considering the relationship between benzene levels and other variables monitored within an AQMN, such as NO2, O3, temperature, solar radiation, and accumulated precipitation, this study proposes an approach for estimating benzene air concentrations from the related variables. Using the data of the aforementioned variables from 23 fixed stations during 2016-2017, the proposed approach was able to forecast benzene concentration for 2018 with high confidence, providing enriched data on benzene exposure and its trends. Moreover, the spatial distribution of the estimated versus the most representative benzene levels was quite similar. Finally, an artificial neural network identified the most representative fixed benzene monitoring sites within the AQMN.

A methodological framework for improving air quality monitoring network layout. Applications to environment management.

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.

Indoor and Outdoor PM10-Bound PAHs in an Urban Environment. Similarity of Mixtures and Source Attribution.

Given that the European Union lays down air quality objectives associated with outdoor environments, indoor air mixtures' study acquires a remarkable relevance. This work aims to submit a stepwise methodological framework for assessing similarities between indoor and outdoor air mixtures and apportioning potential emission sources. For reaching this goal, PM10 particles were systematically and simultaneously collected at an indoor (dominant emission sources free) and outdoor environment during a year to determine the PAH content in both air mixtures. Broadly, outdoor PAHs levels were higher than at the indoor location, supporting a strong association between both mixtures (r = 0.968, p > 0.001), mainly during the cold period (r = 0.896, p > 0.001). The light molecular weight PAHs were highlighted at the indoor site, in particular to naphthalene and anthracene. Outdoor emission sources influenced the indoor PAH levels, especially high and medium molecular weight PAHs. The local-traffic load was identified as a dominant pollution source responsible for more than half PAHs determined at both environments. Therefore, the control of outdoor emission sources would be translated into an improvement of indoor air quality.

Combination of toxicological and epidemiological approaches for estimating the health impact of atmospheric pollutants. A proof of concept for NO2.

BACKGROUND: Regular monitoring of the air pollutant nitrogen dioxide (NO2), an indicator for traffic-related emissions, is a priority in urban environments. The health impacts associated with NO2 exposure are the result of a combination of factors, including concentration, duration of exposure, and interactions with other pollutants. WHO has established air quality guidelines based on epidemiological studies. OBJECTIVE: This study develops a new concept "Health Impact Pathways (HIPs)" using adversity as a probabilistic indicator of health effects. For this purpose, it integrates available toxicological and epidemiological information, using Adverse Outcome Pathways (AOPs), in order to understand chemical-biological interactions and their consequences on health. METHODS: Literature review and meta-analysis of toxicological data supported by expert judgment were performed to establish: a) adversity pathways, b) quantitative criteria for scoring the observed toxicological effects (adversity indicators), c) NO2 exposure - adversity relationship for both long-term (1-36 months) and shortterm (1-7 days). The NO2 daily concentrations from January 2001 to December 2022, were obtained from Madrid city Air Quality network monitoring database. Adversity levels were compared with relative risk levels for all-cause and respiratory mortality estimated using linear equations from WHO 2021 guidelines. RESULTS: Non-linear relations were obtained for all long- and short-term NO2 related adversity indicators; for long-term effects, the best fitting was obtained with a modified Haber's law model with an exponential coefficient for the exposure time of 0.25. Estimations are presented for a set of case studies for Madrid city, covering temporal and spatial variability. A clear improvement trend along the two decades was observed, as well as high inter- and intra-station variability; the adversity indicators provided integrated information on the temporal and spatial evolution of population level risk. DISCUSSION: The proposed HIP conceptual approach offers promising advances for integrating experimental and epidemiological data. The next step is linking the concentration-adversity relationship with population health impacts through probability estimations, the preliminary estimations confirm the need for assessing independently different population groups.

Health risk assessment of the European inhabitants exposed to contaminated ambient particulate matter by potentially toxic elements.

PM10-associated potential toxic elements (PTEs) can enter the respiratory system and cause health problems. In the current study, the health risk indices caused by PM10 inhalation by adults, children, and infants in 158 European cities between 2013 and 2019 were studied to determine if Europeans were adversely affected by carcinogenic and non-carcinogenic factors or not. The Mann-Kendall trend test examined PM10's increasing or decreasing trend. Random Forest analysis was also used to analyse meteorological factors affecting PM10 in Europe. Hazard quotient and cancer risk were estimated using PM10-associated PTEs. Our results showed a decline in continental PM10 concentrations. The correlation between PM10 concentrations and temperature (-0.40), PBLH (-0.39), and precipitation were statistically strong (-0.21). The estimated Pearson correlation coefficients showed a statistically strong positive correlation between As & Pb, As & Cd, and Cd & Pb during 2013-2019, indicating a similar origin. PTEs with hazard quotients below one, regardless of subpopulation type, posed no noncancerous risk to Europeans. The hazard quotient values positively correlated with time, possibly due to elevated PTE levels. In our study on carcinogen pollution in Europe between 2013 and 2019, we found unacceptable levels of As, Cd, Ni, and Pb among adults, children, and infants. Carcinogenic risk rates were highest for children, followed by infants, adult women, and adult men. Therefore, besides monitoring and mitigating PM concentrations, effective control of PM sources is also needed.

Presence of diclofenac, estradiol, and ethinylestradiol in Manzanares River (Spain) and their toxicity to zebrafish embryo development.

Diclofenac (DCF), 17-ß-estradiol (E2), and 17-α-ethinylestradiol (EE2) are emerging pollutants included in the first watch list agreed by European countries and set in the EU Water Directive. The objective of the present study was the analytical monitoring of DCF, E2, and EE2 in surface water and sediment of the Manzanares River in a stretch that crosses the city of Madrid, Spain, and to assess whether such environmental levels could affect the development of aquatic vertebrates through a zebrafish embryo-larval assay. Samples taken during two campaigns in the spring of 2015 were analyzed for DCF, E2, and EE2 by LC-MS or GC-MS. The levels of E2 and EE2 measured in surface water and sediments of the Manzanares were within the ranges reported in other Spanish and European studies; however, DCF levels were higher in the present study. The zebrafish embryos exposed to the Manzanares River water (0-144h) showed lethal effects and sublethal effects (developmental delay, bradycardia, and reduced locomotion). Nevertheless, these effects were not primarily associated with the levels of DCF, E2, and EE2 present in the Manzanares River, because representative mixtures of the field study prepared in the laboratory did not exhibit such toxicity to the zebrafish embryos.