Nuevas metodologías de análisis de pesticidas por electroforesis capilar

Los pesticidas son compuestos ampliamente utilizados para la obtención de altos rendimientos agrícolas. Esta denominación incluye una amplia variedad de productos muy diferentes en su composición y propiedades a pesar de su utilización común. Muchos de ellos presentan una alta toxicidad así como una gran persistencia y movilidad medioambiental, lo que los convierte en uno de los grupos de contaminantes más importantes. Se han detectado residuos de pesticidas en alimentos, aguas, suelos, fluidos biológicos, etc, y en lugares tan remotos como la Antártida o el Ártico . El problema de la presencia de residuos de pesticidas en los alimentos está tomando una importancia cada vez mayor, hasta tal punto que, actualmente, se ha convertido en una constante preocupación para los consumidores. A la vista de la legislación vigente, así como de las directrices tanto europeas como estatales y autonómicas existentes en lo que a materia de seguridad alimentaria se refiere, se hace necesario el desarrollo de metodologías analíticas que permitan determinar residuos de pesticidas en un amplio espectro de matrices, a nivel de sus límites máximos de residuos (LMR). Además, estas nuevas metodologías desarrolladas deben ser rápidas, fiables y compatibles con el medio ambiente. Los más recientes artículos de revisión muestran los diferentes procedimientos de extracción a los que se suelen someter las muestras (principalmente aguas, suelos y frutas) para su posterior análisis y cuantificación, en lo que a contenido en pesticidas se refiere. En este sentido, las técnicas de pretratamiento de muestras más utilizadas son la extracción en fase sólida (SPE), la microextracción en fase sólida (SPME) y la extracción líquido-líquido (LLE) -esta última cada vez menos- aunque actualmente se están utilizando en mayor número técnicas como la extracción asistida por microondas o la extracción con fluidos supercríticos

Sample treatments prior to capillary electrophoresis-mass spectrometry

Sample preparation is a crucial part of chemical analysis and in most cases can become the bottleneck of the whole analytical process. Its adequacy is a key factor in determining the success of the analysis and, therefore, careful selection and optimization of the parameters controlling sample treatment should be carried out. This work revises the different strategies that have been developed for sample preparation prior to capillary electrophoresis-mass spectrometry (CE-MS). Namely, the present work presents an exhaustive and critical revision of the different samples treatments used together with on-line CE-MS including works published from January 2000 to July 2006Authors are grateful to the AGL2005-05320-C02-01 Project (Ministerio de Educacion y Ciencia) and the ALIBIRD-S-505/AGR-0153 Project (CAM) for financial support of this work.Peer reviewe

Microplastics in snow of a high mountain national park: El Teide, Tenerife (Canary Islands, Spain)

Human activities have introduced high amounts of microplastics (MPs) into the atmosphere that can be transported long distances and be later deposited in terrestrial and aquatic ecosystems with precipitation (rain or snow). In this work, it has been assessed the presence of MPs in the snow of El Teide National Park (Tenerife, Canary Islands, Spain, 2150–3200 m above sea level) after two storm episodes (January–February 2021). The data set (63 samples) was divided into three groups: i) samples from “accessible areas” (after the first storm episode and in places with a strong previous/recent anthropogenic activity); ii) “pristine areas” (after the second storm episode, in places with no previous anthropogenic activity), and iii) “climbing areas” (after the second storm episode, in places with a soft recent anthropogenic activity). Similar pattern profiles were observed among sampling sites in terms of morphology, colour and size (predominance of blue and black microfibers of 250–750 μm length), as well as in composition (predominance of cellulosic -either natural or semisynthetic-, with a 62.7 %, polyester, 20.9 %, and acrylic, 6.3 %, microfibers); however, significant differences in MPs concentrations were found between samples collected in pristine areas (average concentration of 51 ± 72 items/L) and those obtained in places with a previous anthropogenic activity (average concentration of 167 ± 104 and 188 ± 164 items/L in “accessible areas” and “climbing areas”, respectively). This study shows, for the first time, the presence of MPs in snow samples from a high altitude protected area on an insular territory and suggests that the sources of these contaminants could be atmospheric transport and local human outdoor activitie

Recycled wastewater as a potential source of microplastics in irrigated soils from an arid-insular territory (Fuerteventura, Spain)

In this work, the occurrence of microplastics (MPs) in irrigation recycled wastewaters (RWWs) and a desalinated brackish water (DBW) from the arid territory of Fuerteventura (Canary Islands, Spain) was studied. Besides, the presence of MPs in two types of soils (sandy-loam and clay-loamy; with no mulch film or fertilization with sewage sludge applied) irrigated with both water qualities was addressed. Results showed the prevalence presence of cellulosic and polyester microfibers (between 84.4 and 100%) of blue and transparent colors (up to 55.6 and 33.3%, respectively), with an average length of 786.9 ± 812.1 μm in the water samples. DBW had the lowest MP concentration (2.0 ± 2.0 items·L−1) while RWW showed concentrations up to 40.0 ± 19.0 items·L−1. Similarities were also observed between the MPs types and sizes found in both soils top layer (0–5 cm), with an average concentration three times greater in soil irrigated with RWW than in soil under DBW irrigation (159 ± 338 vs. 46 ± 92 items·kg−1, respectively). In addition, no MPs were extracted from non-irrigated/non-cultivated soils, suggesting agricultural activities as the unique source of MPs in soils of this arid area. Results show that RWWs constitute a potential source of MPs in irrigated soils that should be considered among other pros and cons linked to the use of this water quality in agricultural arid land

Microplastics determination in gastrointestinal tracts of european sea bass (Dicentrarchus labrax) and gilt-head sea bream (Sparus aurata) from Tenerife (Canary Islands, Spain)

Microplastic pollution has an extremely widespread distribution, to the extent that microplastics could be ingested by aquatic organisms, including species of commercial importance for fisheries and aquaculture. In this work, the anthropogenic particles content of the gastrointestinal tracts of 86 individuals of cultivated European sea bass (Dicentrarchus labrax, n = 45) and gilt-head sea bream (Sparus aurata, n = 41) from Tenerife (Canary Islands, Spain) was determined. Samples were bought at local markets and directly transported to the laboratory. After the dissection of the fishes and digestion of the gastrointestinal tracts in 10% KOH (w/v) at 60◦C for 24 h, the digests were filtered (50 µm stainless-steel mesh) and visualized under a stereomicroscope, finding that most of the items were colourless (47.7% for Dicentrarchus labrax and 60.9% for Sparus aurata) and blue (35.3% vs. 24.8%) microfibers, with an average length of 1957 ± 1699 µm and 1988 ± 1853 µm, respectively. Moreover, 15.3% of the microfibres were analysed by Fourier transform infrared spec-troscopy, showing the prevalence of cellulosic fibres together with polyester, polyacrylonitrile, and poly(ether-urethane). This pattern (microplastics shapes, colours, sizes, and composition) clearly agrees with previous studies carried out in the Canary Islands region regarding the determination of microplastics in the marine environmen

Determination of phthalic acid esters and di(2-ethylhexyl) adipate in fish and squid using the ammonium formate version of the QuEChERS method combined with gas chromatography mass spectrometry

In the present study, the ammonium formate version of the QuEChERS method, considered highly advantageous in relation to instrument maintenance and other issues, was applied for the first time to extract a group of twelve phthalic acid esters (PAEs, i.e. dipropyl phthalate, DPP; diisobutyl phthalate, DIBP; dibutyl phthalate, DBP; diisopentyl phthalate, DIPP; di-n-pentyl phthalate, DNPP; dihexyl phthalate, DHP; butyl benzyl phthalate, BBP; dicyclohexyl phthalate, DCHP; di(2-ethylhexyl) phthalate, DEHP; di-n-octyl phthalate, DNOP; diisononyl phthalate, DINP; and diisodecyl phthalate, DIDP) and one adipate (di(2-ethylhexyl) adipate, DEHA) from two species of fish (Scomber colias and Katsuwonus pelamis) and one of squid (Loligo gahi). The method was validated in terms of linearity, trueness and matrix effects. Determination coefficients (R2 ) for matrix-matched calibration curves were higher than 0.99 in all cases, being the lowest calibration levels in the range 0.5–10 ng/g. Mean recovery values were between 70 and 117% with relative standard deviation values ≤20%. Matrix effects were soft (between − 20 and +20%) for most analytes and matrices, except in squid samples, which was mostly medium with a moderate ion suppression. The analysis of 10 samples of each type showed the presence of DIBP, DBP and DEHP at concentrations up to 44.2 ± 2.1 ng/g of wet weight in some of the samples and species, still not representing concerning values when considering the daily intake of such species of seafood in the human diet (tolerable daily intake -TDI- values were not exceeded). Results demonstrated that the ammonium formate version of the QuEChERS method can be applied with success for the extraction and determination of the selected PAEs and DEHA in fish and squid samples.info:eu-repo/semantics/publishedVersio

Exploring the origin and fate of surface and sub-surface marine microplastics in the Canary Islands region

The presence of different types of microplastics (MPs) in the Atlantic Ocean has been well-documented, with data collected from the Canary Islands indicating high concentrations of MPs at four different beaches (hot spots). However, critical gaps persist regarding the abundance of MPs in diverse open ocean regions, at varying depths, and their transport behavior and origin. This study aims to evaluate, for the first time, the large-scale (>100 km) and mesoscale (10-100 km) ocean dynamic processes and the resulting transport of MPs in the region. On the one hand, this study investigates the surface velocity of currents between 27-32°N latitude range, establishing correlation with the accumulation of MPs on diverse beaches across several islands of the archipelago. This analysis goes beyond studying the predominant current by integrating data at a smaller geographical scale over a two-year period. Concurrently, previous and ongoing research suggests the presence of small MPs (SMPs,<1 mm) at high concentration at a depth of 1100 meters in this region. By integrating these vertical profiles of MPs with a deep understanding of the physical processes of the Canary region accumulated over decades of research, our study introduces an innovative model that outlines how SMPs are sink and transported in open oceans by water mases. This comprehensive approach not only enhances our understanding of the complex dynamics influencing the distribution of MPs but also provides crucial insights to address the widespread problem of MP pollution in the Atlantic

Microplastic pollution in sublittoral coastal sediments of a North Atlantic island: The case of La Palma (Canary Islands, Spain)

In this work, the microplastic content of sediments collected in July 2020 between 5 and 7 m depth was studied in four locations of La Palma island (Canary Islands, Spain). At each sampling location, three samples were taken parallel to the shoreline. The microplastic content in each sampling corer was studied every 2.5 cm depth after digestion with a H2O2 solution followed by flotation in a saturated NaCl solution. Visualization of the final filtrates under a stereomicroscope revealed that all the sediment samples evaluated contained mostly microfibers (98.3%) which were mainly white/colorless (86.0%) and blue (9.8%), with an average length of 2423 ± 2235 (SD) mm and an average concentration of 2682 ± 827 items per kg of dry weight, being the total number of items found 1,019. Fourier Transform Infrared microscopy analysis of 13.9% (n = 139) of the microfibers also showed that they were mainly cellulosic (81.3%). No significant differences were found between the depths of the sediment. However, significant differences were found between the number of fibers from the sampling sites at the east and west of the island. Such variability could be driven by the winds and ocean mesoscale dynamics in the area. This study confirms the wide distribution of microfibers in sediments from an oceanic island like La Palma, providing their first report in marine sediments of the Canary Islands.En prensa3,20

Bioinformatics Discovery of Vertebrate Cathelicidins from the Mining of Available Genomes

Due to the worrying increase in antimicrobial resistance to conventional antibiotics, the search for alternatives is becoming increasingly important. Antimicrobial peptides (AMPs), originating from natural resources, have been recognised as a novel class of antibiotics. An advantage of peptides over antibiotics is that the resistance is more difficult to attain than for conventional antibiotics. With the increasing number of genomes sequenced and available in the public domain, one alternative methodology to obtain novel AMPs is to analyse genes and proteins from genomic databases to predict and identify amino acid sequences that share similarities and molecular features with natural bioactive antimicrobial peptides. In this chapter, we summarise some of our recent results on the production of antimicrobial peptides, particularly, how we managed to identify a family of antimicrobial peptides: cathelicidins, through bioinformatics tools, from the genomes of two lower vertebrates (a reptile and a bird) available in public databases. We hope that our preliminary investigation with these novel peptides could be useful for the design of future strategies that pursue the production of antimicrobial peptides through biotechnology

Risk factors and typification of suicidal behavior in adolescence, its community focus

Introducción: dentro de las tres causas de muerte más frecuentes en adolescentes de 15 y más años de edad se encuentra el suicidio.Objetivo: caracterizar los factores de riesgo y la tipificación de la conducta suicida en adolescentes dispensarizados en la atención primaria desde el enfoque comunitario.Métodos: se realizó en el Policlínico “Marta Abreu” un estudio descriptivo, transversal y observacional desde enero de 2016 a diciembre de 2018 con una población de 72 adolescentes. Se utilizaron el análisis documental y la aplicación de encuesta para caracterizar los riesgos y tipificar en caso de intento suicida previo consentimiento informado familiar y adolescente.Resultados: predominó el sexo masculino en edades comprendidas entre 13 y 15 años, con factores de riesgo individual, familiar y escolar, el método de empleo fue el consumo de tabletas.Conclusiones: factores de riesgo más frecuentes: un miembro de su familia se embriaga frecuentemente, acoso en la escuela, no le gusta estudiar y dificultades en la relación con los padres. El sexo masculino resultó el más significativo en el intento, con método de letalidad riesgosa no letal, gravedad moderada de la circunstancia y poco serio con la ingestión de fármacos, con gran importancia desde su enfoque comunitario y atención multidisciplinaria.Introduction: suicide is one of the three most frequent causes of death in adolescents aged 15 and over.Objectives: to characterize the risk factors and the typification of suicidal behavior in adolescents registered in primary care from the community approach.Methods: a descriptive, transversal and observational study was carried out at Policlinic "Marta Abreu" from January 2016 to December 2018 with a population of 72 adolescents. Documentary analysis and survey were used to characterize the risks and typify in the case of a suicide attempt with the prior informed consent of the family and the adolescent.Results: male sex predominated in ages 13 to 15, with individual, family and school risk factors, the method of use was the consumption of tablets.Conclusions: most frequent risk factors: a family member gets drunk frequently, bullying at school, does not like to study, and difficulties in the relationship with parents. The male sex was the most significant in the attempt, with a non-lethal method of risk lethality, moderate severity of the circumstance and not very serious with the ingestion of drugs, with great importance from its community approach and multidisciplinary care