Miguel Izquierdo

• PhD Environmental Research, Modelling and Risk Assessment
• Professor (Assistant) at Universidad Politécnica de Madrid

The radon-deficit technique has proven to be a valuable tool for environmental site characterization, particularly in detecting subsurface organic contamination. This work highlights its successful application in two contaminated sites, validated by consulting firms and supported by independent data collection campaigns. In the first case study, th...

This study applies a Screening-Level Ecological Risk Assessment (SLERA) to evaluate the potential impact of trace elements on vegetation in an abandoned As–Cu mining area in northern Spain. A total of 27 soil samples were analyzed for pseudo-total (aqua regia) and phyto-available (EDTA 0.05 M) content of As, Cd, Co, Cr, Cu, Ni, Pb and Zn. Contamina...

The Water Framework Directive (WFD, 2000/60/EC) mandates member states to consider trace element background values when establishing environmental quality standards (EQS) for sediments. This study proposes defining the "background" value as the trace element concentration that is consistently present in the unaltered natural environment, and the "r...

The Radon deficit technique is a promising screening method for identifying and mapping potential subsurface organic pollution hotspots and thus, for the optimization of intrusive characterization campaigns. Radon (222 Rn) a naturally procuded radionucleid and particularly suitable for use as a natural tracer due to its preferential partitioning wi...

This study proposes using the network of urban gardens to grow vegetables and to monitor air quality, and it also evaluates whether food grown on a clean substrate in an urban environment is safe for consumption. For this purpose, lettuces were exposed to different degrees of air pollution in five locations in the city of Copenhagen, plus a referen...

Human Health Risk Assessment (HHRA) is a widely applied method to make decisions about the environmental status of sites affected by toxic substances. Its conclusions are affected by the variability and uncertainty of the input variables in the HHRA model. The aim of this work is to apply an algorithm based on 2D Monte Carlo simulations to integrat...

Recientemente, se ha incrementado el uso de técnicas tomográficas de resistividad eléctrica y de polarización inducida en el estudio de emplazamientos contaminados por fases no acuosas. Este enfoque produce los mejores resultados en la detección de fases ligeras (LNAPL). Este trabajo presenta los resultados obtenidos en la caracterización de un emp...

This chapter extends a previous experience of educational innovation carried out at the E.T.S.I. Minas y Energía of the Universidad Politécnica de Madrid, deepening the analysis of the impact that training exercises with controlled errors has on learning. Based on the results obtained in the marks of the evaluable tests in three different subjects,...

La omnipresencia del radón en el subsuelo y su reparto preferencial con fases orgánicas hacen de este gas un trazador eficaz de la contaminación orgánica. Sin embargo, existen ciertos parámetros ambientales que pueden afectar a su determinación analítica en campo y que, por tanto, pueden agregar factores de confusión en la vinculación del descenso...

The health crisis caused by the SARS-COV-2 virus produced a drastic change in teaching in March 2020, when face-to-face teaching was forced to become online teaching. It led to changes in teaching methodologies, teaching materials and evaluation methods. The objective of this study is to determine which of these changes in the on-site university ha...

In the present paper, the authors attempt to explain the importance of pH in the soil environment studies and show what mistakes to avoid when measuring pH and interpreting the results obtained. The tests conducted (i.e. extraction in aqua regia, buffer capacity determination, and the impact of acidification on the amount of heavy metals extracted...

The radon-deficit technique is a powerful tool to detect and delineate sub-surface accumulations of organic contaminants. Field measurements of ²²²Rn in soil air, however, are affected by several confounding factors that can lead to the misinterpretation of results. Among the most influential are: vertical and lateral changes of lithology, fluctuat...

The information obtained in the initial characterization of contaminated sites is essential for their correct environmental assessment, management and eventual remediation. In the case of organic contaminants, conventional techniques (i.e. drilling and installation of monitoring wells) may be unsuccessful if preliminary information on the location...

The detection and accurate delineation of subsurface accumulations of Dense Non-Aqueous Phase Liquids (DNAPLs) with standard characterization techniques is a particularly challenging problem because of their gravity-driven migration mechanisms and their resulting heterogeneous spatial distribution. The development and application of high resolution...

This work presents a case study using electrical resistivity tomography at a site mainly affected by the presence of residual lindane coming from a close landfill constructed by an old pesticide manufacturer. In addition, the landfill also collected chlorinated contaminants derived from the same industry. Lindane itself is a highly toxic contaminan...

La crisis sanitaria producida por el virus del SARS-COV-2 produjo un cambio drástico en la educación en marzo de 2020, cuando la enseñanza presencial se vio forzada a adaptarse a la telenseñanza. Esto produjo cambios en las metodologías docentes, los materiales didácticos y los métodos de evaluación. El objetivo de este estudio es determinar cuáles...

En este artículo se presenta la experiencia de innovación docente introducida en asignaturas impartidas en la E.T.S.I. Minas y Energía de la Universidad Politécnica de Madrid, basada en el entrenamiento con ejercicios que contienen errores controlados. Se analizan los resultados obtenidos con el empleo de esta metodología y su impacto en el aprendi...

The performance of the radon (222 Rn)-deficit technique has been evaluated at a site in which a complex DNAPL mixture (mostly hexachlorocyclohexanes and chlorobenzenes) has contaminated all four layers (from top to bottom: anthropic backfill, silt, gravel and marl) of the soil profile. Soil gas samples were collected at two depths (0.8 m and 1.7 m)...

An openly accessible cellular automaton has been developed to predict the preferential migration pathways of contaminants by surface runoff in abandoned mining areas. The site where the validation of the results of the Contaminant Mass Transfer Cellular Automaton (CMTCA) has been carried out is situated on the steep flank of a valley in the Spanish...

This work presents the preliminary results of the initiative carried out in an engineering school for the implementation of 3D printing as a technological teaching tool in its training programmes through the creation of a fabrication laboratory (FabLabs). This initiative is framed within the educational innovation project "Implementation of FabLabs...

A blind field test with 136 independent measurements of radon (²²²Rn) in soil air retrieved from a depth of 0.8 m in a decommissioned lindane (γ-hexachlorocyclohexane) production plant was undertaken to evaluate the performance of the ²²²Rn-deficit technique as a screening methodology for the location and delineation of subsurface accumulations of...

Geochemistry has become an essential subject to understand our origins and face the challenges that humanity will meet in the near future. This book presents several studies that have geochemistry as their central theme, from the description of different geological formations, through its use for the characterization of contaminated sites and their...

Tutoring is an essential didactic resource of the learning process, in which students can receive specific attention about particular doubts and understanding problems. However, the personalized assistance to the problems that occurred during the autonomous learning process outside of the classroom has a delay when the tutoring takes place in perso...

In the last decade, many alternative teaching methodologies have been developed, all of them belonging to the framework of educational innovation, with the aim of encouraging students' motivation, adapting to new technologies and improving learning. Specifically, this study focuses on the use of tutorial videos in which the explanation of some topi...

Project Management in engineering fields is being transformed towards an agile management, where the interaction with the client / user and iteration is a constant. For the success of the project, and the resolution of the engineering problem, new learning tools must be considered, where the student must work, among others, creativity competences (...

Tutoring is an essential didactic resource of the learning process, in which students can receive specific attention about particular doubts and understanding problems. However, the personalized assistance to the problems that occurred during the autonomous learning process outside of the classroom has a delay when the tutoring takes place in perso...

Los pasivos mineros pueden incorporar al medio ambiente concentraciones de metales pesados que pueden suponer un riesgo para la salud humana y los ecosistemas. Especialmente en escenarios de minería abandonada en zonas rurales, es fundamental comprender y predecir la transferencia de dichos metales, a través de la escorrentía superficial, desde sus...

The objective of the study was to determine the concentration of trace elements in the surroundings of Carreña de Cabrales (Spain), a town located on the foothills of three mine entrances and two tailings dams. For this purpose, 19 soil samples were collected, as well as 8 surface water and 6 sediment samples from a river running through the locali...

Non-Aqueous Phase Liquids (NAPLs) are the object of global concern since they pose risks to human and environmental health. The characterization of NAPL plumes, arising from spills and leaks from landfills and industrial facilities, and the monitoring of remediation processes are challenging tasks, specially in the case of Dense NAPLs (DNAPLs). The...

High school students start their first year at the university with very different levels of knowledge and skills. Chemistry and Technical Drawing are two appropriate examples to study this complex situation. Due to the flexible high school academic curricula and the lack of strict requirements to enter university degrees in the case of, for example...

High school students start their first year at the university with very different levels of knowledge and skills. Chemistry and Technical Drawing are two appropriate examples to study this complex situation. Due to the flexible high school academic curricula and the lack of strict requirements to enter university degrees in the case of, for example...

Information and Communications Technologies (ICTs) have been widely used to improve the process of learning. The flipped-classroom technique seeks to encourage the self-learning of the students through online lectures, allowing them to use their time in the face-to-face lessons to apply the theoretical concepts and practical methodologies. In this...

This study evaluates the results of the characterization of air pollution in urban green areas using edible plants. To this purpose, we examined the effect of location (i.e., three different levels of pollution), substrate (peat moss and vermiculite), and plant species (oilseed rape [Brassica napus L.] and kale [Brassica oleracea L.]) on the accumu...

Despite the environmental, economic and social benefits of urban gardening, there are also potential threats to human health due to the possible enrichment of urban soils in anthropic contaminants. As of today, our knowledge about the influence of population characteristics and local habits of garden use on risk estimates is incomplete. This work s...

In undergraduate university degrees, students start their first year with a high level of heterogeneity in terms of acquired curricular competences. Therefore, the teaching given in these courses must face the challenge of turning this heterogeneity, in principle counterproductive, into an added value that helps students to face the subjects with e...

El uso conjunto de la gamificación y las nuevas tecnologías de comunicación tiene un fuerte potencial para mejorar el aprendizaje en todos los niveles educativos. El presente trabajo estudia la implantación de un sistema de gamificación en una asignatura de máster universitario, utilizando la herramienta Kahoot!, la cual utiliza dispositivos móvile...

Students start university with a high heterogeneity, both in knowledge and abilities to cope with the different subjects. Traditional teaching methods are based on unidirectional transmission of knowledge, from teachers to students, causing problems when the aforementioned heterogeneity is high. Some new methods try to homogenize the students befor...

This chapter discusses the analytical protocols that have been developed to assess the bioaccessibility of contaminants potentially able to impact human health. In order to evaluate a contaminant's bioaccessibility, the physiological conditions of the gastrointestinal tract or lung environment must be reproduced in the laboratory. Most research eff...

The applicability of radon (²²²Rn) measurements to delineate non-aqueous phase liquids (NAPL) contamination in subsoil is discussed at a site with lithological discontinuities through a blind test. Three alpha spectroscopy monitors were used to measure radon in soil air in a 25,000-m² area, following a regular sampling design with a 20-m² grid. Rep...

The quantitative characterization of exposure factors is a critical point in human health risk assessment since those factors strongly control the numerical result of such assessment. As opposed to a deterministic approach, which makes use of single values for each input variable, probabilistic risk assessments consider random variables in the inta...

The quantitative characterization of exposure factors is a critical point in human health risk assessment since those factors strongly control the numerical result of such assessment. As opposed to a deterministic approach, which makes use of single values for each input variable, probabilistic risk assessments consider random variables in the inta...

A total of 74 samples of soil, sediment, industrial sludge, and surface water were collected in a Mediterranean estuarine system in order to assess the potential ecological impact of elevated concentrations of Co and Mn associated with a Terephthalic (PTA) and Isophthalic (PIPA) acids production plant. Samples were analyzed for elemental compositio...

In order to characterize the influence of envi-ronmental factors in dust metal loadings inside homes in an urban environment and to evaluate the associated potentialhealth risks, samples of settled indoor dust from 10 apartments in the urban area of Madrid (Spain) were collectedwith wet wipes. Cd, Cr, Cu, Pb, Zn, Ni, and Mn loads weredetermined by A...

This study examines the suitability of using edible plants for atmospheric pollution biomononitoring, analysing three variables: localization (exposure sites with different degree of pollution), substrate and specie. Samples exposed near the road exhibit a higher concentration of several trace elements associated with traffic sources. On the other...

El principal problema de las explotaciones mineras de sulfuros es la contaminación de los recursos hídricos por procesos de Drenaje Ácido de Mina (AMD). El proceso contaminante provoca, además, la aparición de ecosistemas estructuralmente simples dominados por organismos acidófilos, ya sean procariotas o eucariotas. Desde una perspectiva de monitor...

Risk assessment is the process of modelling exposure to a toxicant and predicting health effects. Probabilistic Risk Assessment (PRA) allows to characterize variability and uncertainty in risk estimates, and may be particularly useful when point estimates of risk are unacceptably high, when environmental justice issues are raised or when exploring...

Methods to perform a Probabilistic Environmental Risk assessment from exposure to toxic substances - i.e. USEPA (1997) <https://www.epa.gov/risk/guiding-principles-monte-carlo-analysis> -.

Rn emanometry has been validated as screening technique of sites affected by non-aqueous phase liquids (NAPLs) where the subsurface structure does not present significant spatial variations. When there are fractures or changes in soil permeability, background emanation varies spatially, making it difficult to discriminate whether the decrease in th...

This paper discusses the geochemical behaviour of arsenic (As), antimony (Sb) and selenium (Se) in urban gardens and the human health implications associated with urban agriculture. A total of 42 samples from 7 urban gardens in Madrid (Spain) were collected from the top 20 cm of soil. Concentrations of As, Sb and Se and the main soil properties (i....

A simple analytical method using low volumes of solvent for determining selected PAHs and NPAHs in PM samples is presented. The proposed extraction method was compared with pressurized fluid (PFE) and microwave (MC) extraction techniques and intermediate precision associated to analytical measurements were estimated. Extraction by agitation with 8...

Trace elements are present in indoor dust and can pose a risk to the health of children (especially vulnerable because of their differences in development and behavior from adults). Dust samples from 10 homes in Madrid wer e collected with sampling wipes. Entrance hall, kitchen, living room and master bedroom were sampled. Samples were digested wit...

As aircraft traffic grows and other combustion sources become cleaner, the potential importance of aircraft related emissions increases in relation to both health and environmental effects. There is currently minimal data available to provide speciation profiles of polynuclear aromatic hydrocarbons (PAH) for local air quality analysis purposes. INT...

As the aviation sector continues to grow into the future, there is concern about atmospheric and Local Air Quality (LAQ) particle emissions and their impact on the environment and on human health (Waitz, 2004). Within this study, a series of particulate emissions experiments were carried out on different turbofan engines at INTA Turbojet Test Centr...

The determination of polycyclic aromatic compounds (PACs) in aerosols is still an attractive target for analytical purposes. However, the analysis is complicated for samples with very low mass loading, for which the sample preparation often involve a large consume of time and solvent, with a high risk of loss of analytes. It is necessary to stress...