Person: Cáceres, Jorge Omar
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First Name
Jorge Omar
Last Name
Cáceres
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Analítica
Area
Química Analítica
Identifiers
13 results
Search Results
Now showing 1 - 10 of 13
Item Evaluating urban indoor and outdoor PM10-bound organochlorine pesticides. Air quality status and health impact(Building and Environment, 2023) Galán-Madruga, David; Cárdenas-Escudero, Jafet; Broomandi, Parya; Cáceres, Jorge Omar; González, María del CarmenPM10-bound OCPs were collected simultaneously for a year at an outdoor and indoor location in Madrid City, Spain. They were extracted by accelerated solvent extraction and quantified by GC/EM. The aim was to solve the lack of scientific information concerning that environmental scenery by acquiring knowledge on air quality status and health impact. Outdoor and indoor air annual average PM10‐bound ƩOCPs concentration was 684.81 and 721.72 pg/m3, with significant contribution of the molecular weight OCPs lower than 400 g/mol. Hexachlorobenzene and dieldrin displayed the highest concentrations individually, whereas heptachlor and 2,4′-DDD and 2,4′-DDT were the lowest ones. Although higher OCPs concentrations in the cold than warm period were determined, a high outdoor vs indoor correlation was observed over the entire study (r = 0.999). The more representative OCPs within the target air mixtures drove to hexachlorobenzene (outdoor and indoor air) in addition to mirex (outdoor) and 4,4′-DDE (indoor). I/O air pollutant ratios were higher than one for all target compounds except for dieldrin. Whereas the estimated carcinogenic risk falls within the acceptable range set by the US‐EPA (<10−4) for each target pollutant, except for outdoor dieldrin (winter and spring), the accumulated seasonal levels are above the acceptable risk in outdoor (for all seasons) and indoor (winter and spring). Although the use of OCPs has been banned in preterit times, their assessment should still be addressed to know outdoor and indoor human exposure to these pollutants and to adopt efficient remediation measures.Item Mg/Ca ratios measured by Laser Induced Breakdown Spectroscopy (LIBS): a new approach to decipher environmental conditions(Journal of Analytical Atomic Spectrometry, 2015) García Escarzaga, Asier; Moncayo Martín, Samuel; Gutiérrez Zugasti, Igor; González Morales, Manuel R.; Martín Chivelet, Javier; Cáceres, Jorge OmarThe potential application of Mg/Ca ratios in top shells of the mollusc species Phorcus lineatus (Da Costa, 1778) obtained by Laser Induced Breakdown Spectroscopy (LIBS) have been evaluated as an environmental proxy to reconstruct paleotemperatures and season of capture of molluscs for the first time. All samples were collected from Cantabrian Sea (Spain). The results were compared with instrumental sea surface temperatures (SST) and with a known reliable proxy as oxygen isotope ratio (δ18Oshell) which is mainly dependent on SST, obtained from the same shells. The measurements were taken in two different biominerals of the shell (aragonite and calcite) resulting in a correlation between Mg/Ca ratios and SST of R2= 0.43 and 0.44, respectively. Mg/Ca ratios were also studied through a long sequence on three shells collected in autumn 2012. Results show variations in Mg/Ca ratios related to seasonal changes in SST through the year and a good correlation between Mg/Ca ratios and δ18Oshell in two shells (R2= 0.70 and 0.65, respectively).Item Lycopene. A review of chemical and biological activity related to beneficial health effects(Lycopene. A review of Chemical and Biological Activity Related to Beneficial Health Effects , 2013) Cáceres, Jorge Omar; Cámara Hurtado, María De La Montaña; Manzoor, Sadia; Fernández Ruiz, Virginia; Sánchez Mata, María De Cortes; ElsevierThis work focuses on the developments related to lycopene, a natural carotenoid and bioactive compound, particularly with reference to its chemistry and biological activity and its potential health effects. The formation of free radicals or other compounds in the body that are able to oxidize lipids, proteins, and DNA (also known as oxidative stress) is one of the major risk factors for chronic diseases. There is considerable evidence that lycopene has a protective effect against cardiovascular disease, hypertension, atherosclerosis, skin damage, and certain types of cancer such as prostate, breast, lung, and others. Because of this, the presence of lycopene in the diet is considered to be of great value. Dietary lycopene may increase the lycopene level in the body and act as an antioxidant. It may trap reactive oxygen species resulting in an increase in the overall antioxidant potential or a reduction in the oxidative damage to lipids (lipoproteins, membrane lipids), proteins (important enzymes), and DNA (genetic material), thereby lowering the oxidative stress. Alternatively, the increase in serum lycopene level may regulate gene functions, with the enhancement of intercellular communication (responsible for cell growth), modulating hormonal and immune response, regulating metabolism, and thus lowering the risk of chronic diseases. These mechanisms may also be interrelated and may act simultaneously to provide health benefits. Lycopene is quickly absorbed from different food sources (mainly tomato products) and distributed to corporal tissues where it maintains its antioxidant properties. This absorption varies depending on various factors such as food source, food processing, and other components in the diet. The human body is unable to synthesize carotenoids, such as lycopene, so a suitable diet intake is necessary to reach the adequate levels. In this review, the new developments in lycopene analysis by spectroscopic and chromatographic techniques along with mathematical modeling are also considered. These advances have made it possible to evaluate and determine the biological activity of lycopene in natural products. All this knowledge about the chemistry and biological activity of lycopene will be very helpful for the food industry, providing new opportunities in the field of food product development.Item FTIR-ATR detection method for emerging C3-plants-derivated adulterants in honey: Beet, dates, and carob syrups(Talanta, 2023) Jafet Cárdenas-Escudero; David Galán-Madruga; Cáceres, Jorge OmarThe European Union Publications Office has recently presented a report on the European Union’s coordinated action with the Joint Research Centre to determine certain fraudulent practices in the honey sector, in which it has been indicated that 74% of the samples analyzed, imported from China, and 93% of the samples analyzed, imported from Turkey, the two largest honey producers worldwide, presented at least one indicator of exogenous sugar or suspicion of being adulterated. This situation has revealed the critical state of the problem of honey adulteration worldwide and the need to develop analytical techniques for its detection. Even though the adulteration of honey is carried out in a general way with sweetened syrups derived from C4 plants, recent studies have indicated the emerging use of syrups derived from C3 plants for the adulteration of honey. This kind of adulteration makes it impossible to analyze its detection using official analysis techniques. In this work, we have developed a fast, simple, and economical method based on the Fourier transform infrared spectroscopy technique, with attenuated total reflectance, for the qualitative, quantitative, and simultaneous determination of beetroot, date, and carob syrups, derived from of C3 plants; whose available bibliography is very scarce and analytically not very conclusive for its use by the authorities. The proposed method has been based on the establishment of the spectral differences between honey and the mentioned syrups at eight different points in the spectral region between 1200 and 900 cm− 1 of the mid-infrared, characteristic of the vibrational modes of carbohydrates in honey, which allows the pre-discrimination of the presence or absence of the syrups studied, and their subsequent quantification, with precision levels lower than 2.0% of the relative standard deviation and relative errors lower than 2.0% (m/m).Item Long-term hydrological changes in northern Iberia (4.9–0.9 ky BP) from speleothem Mg/Ca ratios and cave monitoring (Ojo Guaren˜a Karst Complex, Spain)(Environmental Earth Sciences, 2015) Cruz, J. A.; Turrero, M. J.; Cáceres, Jorge Omar; Marín Roldán, Alicia; Ortega, A. I.; Garralón, A.; Sánchez, L.; Gómez, P.; Muñoz García, María Belén; Edwards, R. L.; Martín Chivelet, JavierAn absolute-dated stalagmite from Kaite Cave (Ojo Guaren ̃ a Karst Complex, N Spain) provides a nearly continuous, high-resolution record of a proxy of regional precipitation patterns through the 4.9–0.9 ka BP interval. This record is based on the Mg/Ca ratio of the calcite and its variation through the stalagmite stratigraphy, which is interpreted to be primarily driven by changes in precipi- tation amount. The calibration of the proxy is supported by the present-day monitoring carried out in the cave for the last 10 years, which reveals a robust inverse relationship between the inter-annual/inter-decadal variability of rain- fall and the Mg concentration of dripwaters and precipi- tating speleothems. The record of paleoprecipitation, based on 2400 Mg/Ca measurements, shows strong variability at inter-annual to inter-decadal scales, and more subtle but significant changes at secular to millennial scales. This long-term paleohydrological evolution outlines five suc- cessive intervals with consistent trends, which are bounded by abrupt shifts in the regional precipitation. These shifts took place at 4.65, 4.2, 2.6, and 1.3 ka BP. Significantly, the intervals of maximum precipitation of the whole record (around 4.9–4.65, 2.6–2.45, and 1.3–1.1 ka BP) can be related with episodes of minimum solar activity and cor- related with cold climatic events elsewhere.Item Megapixel multi-elemental imaging by Laser-Induced Breakdown Spectroscopy, a technology with considerable potential for paleoclimate studies(Nature Scientific Reports, 2017) Cáceres, Jorge Omar; Pelascini, F.; Motto-Ros, V.; Moncayo, Samuel; Trichard, F.; Panczer, G.; Marín Roldán, A.; Cruz, J.A; Coronado, I.; Martín Chivelet, JavierPaleoclimate studies play a crucial role in understanding past and future climates and their environmental impacts. Current methodologies for performing highly sensitive elemental analysis at micrometre spatial resolutions are restricted to the use of complex and/or not easily applied techniques, such as synchrotron radiation X-ray fluorescence micro-analysis (μ-SRXRF), nano secondary ion mass spectrometry (nano-SIMS) or laser ablation inductively coupled plasma mass spectrometry (LAICP-MS). Moreover, the analysis of large samples (>few cm²) with any of these methods remains very challenging due to their relatively low acquisition speed (~1–10 Hz), and because they must be operated in vacuum or controlled atmosphere. In this work, we proposed an imaging methodology based on laser-induced breakdown spectroscopy, to perform fast multi-elemental scanning of large geological samples with high performance in terms of sensitivity (ppm-level), lateral resolution (up to 10 μm) and operating speed (100 Hz). This method was successfully applied to obtain the first megapixel images of large geological samples and yielded new information, not accessible using other techniques. These results open a new perspective into the use of laser spectroscopy in a variety of geochemical applications.Item Local and Remote Sources of Airborne Suspended Particulate Matter in the Antarctic Region(Atmosphere, 2020) Marina Montes, César; Pérez Arribas, Luis Vicente; Anzano, Jesus; Cáceres, Jorge OmarQuantification of suspended particulate matter (SPM) measurements—together with statistical tools, polar contour maps and backward air mass trajectory analyses—were implemented to better understand the main local and remote sources of contamination in this pristine region. Field campaigns were carried out during the austral summer of 2016–2017 at the “Gabriel de Castilla” Spanish Antarctic Research Station, located on Deception Island (South Shetland Islands, Antarctic). Aerosols were deposited in an air filter through a low-volume sampler and chemically analysed using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES). Elements such as Al, Ca, Fe, K, Mg, Na, P, S, Cu, Pb, Sr, Ti, Zn, Hf, Zr, V, As, Ti, Mn, Sn and Cr were identified. The statistical tools together with their correlations (Sr/Na, Al/Ti, Al/Mn, Al/Sr, Al/Pb, K/P) suggest a potentially significant role of terrestrial inputs for Al, Ti, Mn, Sr and Pb; marine environments for Sr and Na; and biological inputs for K and P. Polar contour graphical maps allowed reproducing wind maps, revealing the biological local distribution of K and P (penguin colony). Additionally, backward trajectory analysis confirmed previous affirmations and atmospheric air masses following the Antarctic circumpolar pattern.Item A Review of Atmospheric Aerosols in Antarctica: From Characterization to Data Processing(Atmosphere, 2022) Anzano, Jesus; Abás, Elisa; Marina-Montes, César; Del Valle, Javier; Galán-Madruga, David; Laguna, Mariano; Cabredo, Susana; Pérez-Arribas, Luis Vicente; Cáceres, Jorge Omar; Anwar, JamilOne of the major problems of the present era is air pollution, not only for its impact on climate change but also for the diseases provoked by this scourge. Among the most concerning air pollutants is particulate matter, since it can travel long distances and affect the entire globe. Antarctica is extremely sensitive to climate change and essential for regulating temperature and permitting life on Earth. Therefore, air quality studies in this region are extremely important. The aim of this review is to present the work conducted on the identification and detection of aerosols and particulate matter in the Antarctic region in the last 20 years. These studies revealed a large number of organic and inorganic species. Organochlorine pesticides or polychlorinated biphenyls represent almost 50% of the organic fraction detected in Antarctica. Furthermore, heavy metals such as Hg and Pb were also found in the region related to anthropogenic activities. To summarize, this work detailed different analytical techniques and data processing to help characterize Antarctic aerosols and their potential sources..Item Statistical Tools for Air Pollution Assessment: Multivariate and Spatial Analysis Studies in the Madrid Region(Journal of Analytical Methods in Chemistry, 2019) Núñez Alonso, David; Pérez Arribas, Luis Vicente; Manzoor, Sadia; Cáceres, Jorge OmarThe present work reports the distribution of pollutants in the Madrid city and province from 22 monitoring stations during 2010 to 2017. Statistical tools were used to interpret and model air pollution data. The data include the annual average concentrations of nitrogen oxides, ozone, and particulate matter (PM10), collected in Madrid and its suburbs, which is one of the largest metropolitan places in Europe, and its air quality has not been studied sufficiently. A mapping of the distribution of these pollutants was done, in order to reveal the relationship between them and also with the demography of the region. The multivariate analysis employing correlation analysis, principal component analysis (PCA), and cluster analysis (CA) resulted in establishing a correlation between different pollutants. The results obtained allowed classification of different monitoring stations on the basis of each of the four pollutants, revealing information about their sources and mechanisms, visualizing their spatial distribution, and monitoring their levels according to the average annual limits established in the legislation. The elaboration of contour maps by the geostatistical method, ordinary kriging, also supported the interpretation derived from the multivariate analysis demonstrating the levels of NO2 exceeding the annual limit in the centre, south, and east of the Madrid province.Item Rapid, reliable and easy-to-perform chemometric-less method for rice syrup adulterated honey detection using FTIR-ATR(Talanta, 2023) Cárdenas Escudero, Jafet; Galán Madruga, David; Cáceres, Jorge OmarThe adulteration of honey (Apis mellifera) is a global problem due to its economic, commercial and health implications. The world's leading beekeeping organisation, APIMONDIA, considers that the detection of adulteration in honey is a problem that has not yet been resolved. This evidence of the importance of the intensive development of analytical techniques that allow the unequivocal detection of adulterants in honey, especially those whose use as honey adulterants has recently emerged. This work aims to develop a fast, easy-to-perform, low-cost analytical method to qualitatively and quantitatively determine rice syrup using the Fourier transform infrared spectroscopy (FTIR) technique with attenuated total reflectance (ATR) mode without complex mathematical procedures and sophisticated sample preparation. This study involved the analysis of 256 intentionally rice-syrup-adulterated honey samples and 92 pure honey samples of bee multifloral honey from Spain. The method, based strictly on the determination of the absorbance directly from the samples, at 1013 cm−1 The methodology used no need for previous treatments or preparations and demonstrated the scope for the unequivocal detection of rice syrup in adulterated honey containing equal to or higher than 3% (m/m) or more of this adulterant. Using the Exponential Plus Linear model (r = 0.998) shows high accuracy and precision, in terms of relative error (0.32%, m/m) and coefficient of variation (1.4%). The results of this study have led to the establishment of a maximum absorbance threshold of 0.670 for honey without rice syrup.