Muestreadores pasivos en el estudio de la dinámica de plaguicidas y el impacto ambiental en el agua

RESUMEN: Los plaguicidas son las sustancias con mayor aplicación en la agricultura las cuales pueden contaminar los cuerpos de agua por descarga directa o indirecta, pero los grandes volúmenes y los procesos transformación pueden disminuir la concentración de estas sustancias y sus productos de degradación en las cuencas. Actualmente, los métodos convencionales de extracción tales como: la extracción en fase sólida (SPE) y la micro extracción en fase sólida (SPME) entre otras, no permiten bajos límites de detección, sin embargo bajos niveles de pesticidas y productos de degradación podrían producir toxicidad crónica en diferentes especies. Actualmente el muestreo pasivo es ampliamente usado en el monitoreo de plaguicidas y para el aseguramiento de la calidad del agua debido a que esta metodología es aplicada in estudios de bioacumulación y deteccion a partes por cuatrillón (ppq). Las membranas con mayor uso en el muestreo pasivo son las membranas tipo SPMD (Semi-permeable membrane devices), las cuales permiten la concentración de sustancias lipofílicas y las membranas tipo POCIS (Polar organic chemistry integrative sampler), las cuales permiten concentrar sustancias hidrofílicas. Esta revisión cubre la aplicación de los muestreadores pasivos en el análisis de plaguicidas, en los estudios de biacumulación y en la evaluación de los riesgos ecotoxicológicos. Finalmente los muestreadores pasivos permiten reducir costos, el tiempo de concentración y la cantidad de solventes orgánicos empleados en el tratamiento de muestra, lo que conduce a su clasificación dentro de las tendencias de la “química analítica verde”.ABSTRACT: Pesticides are the most applied substances in agricultural activities which can contaminate water bodies by direct or indirect discharge, but large volumes and natural transformation processes can decrease the concentration of these substances and their degradates in watershed. Currently, conventional extraction methods such as: solid phase extraction (SPE) and solid phase micro extraction (SPME) among others do not permit low detection limits. However low levels of pesticides and degradates could produce chronic toxicity in different species. Nowadays, passive sampling is widespread used for monitoring pesticides and for ensuring the water quality and bioaccumulation studies due to this methodology allows the detection of pollutant from parts per quadrillion (ppq). The most popular membranes used in passive sampling are the semipermeable membrane devices (SPMD), which permit the concentration of lipophilic substances and the polar organic chemical integrative sampler (POCIS), which permits concentration of the hydrophilic ones. This review is about the application of passive samplers in pesticides analysis, the importance of these devices in the bioaccumulation studies and the evaluation of the ecotoxicological risks. Finally, passive sampling allows reducing costs, time and the amount of organic solvent used which classifies it within the environmental trends of “green analytical chemistry”

Contribution of micro‐PIXE to the characterization of settled dust events in an urban area affected by industrial activities

This study aimed to identify possible sources of settled dust events that occurred in an urban area nearby an industrial park, which alarmed the local population. Settled dust was collected in January 2019 and its chemical characterization was assessed by micro-PIXE, focusing on a total of 29 elements. Comparison with chemical profiles of particulate matter from different types of environment was conducted, along with the assessment of crustal enrichment factors and Spearman correlations, allowing to understand which sources were contributing to this settled dust event. A nearby industrial area’s influence was identified due to the contents of Fe, Cr and Mn, which are typical tracers of iron and steel industries.info:eu-repo/semantics/publishedVersio

Occurrence and sorption behaviour of bisphenols and benzophenone UV-filters in e-waste plastic and vehicle fluff

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A Brief Review on Emerging Indoor Chemical Pollutants

Recently, there has been increased concern about emerging pollutants (EPs). Many EPs can be found in consumer products and are regarded as primary indoor contaminants. This review paper focuses on the overview of some emerging indoor chemical pollutants, their negative health effects, appropriate sampling methods, drawbacks associated with them, and the analytical techniques used. Some of the challenges identified during this review included the ease of access to affordable sampling equipment and analytical instruments. More sensitive and cost-effective sampling and analytical equipment should be made available to allow for continuous monitoring of these emerging pollutants, especially in low and middle-income countries

Comparison of indoor air quality during sleep in smokers and non-smokers' bedrooms: a preliminary study

People spend one third of their life sleeping, but the bedroom, as a specific micro-environment, is often neglected when assessing human exposure to air pollutants. However, exposure during sleep may be significant in the long-term to the integrated individual exposure. This study aimed to assess the exposure during sleep, focusing on a multi-pollutant approach (comfort parameters, carbon dioxide - CO2, carbon monoxide - CO, formaldehyde (CH2O), total volatile organic compounds (VOCs), particulate matter - PM2.5 and PM10 - and ultrafine particles, particle number concentrations - PNC - and lung deposited surface area - LDSA). For that, the air quality during sleep (in real conditions) was monitored using real-time devices in 12 bedrooms of urban (Lisbon and Vila Franca de Xira) and rural (Ponte de Sor) areas of Portugal for one night. Volunteers were smokers and non-smokers. Considering the Portuguese legislation for indoor air quality (IAQ), 67% of the bedrooms registered CO2 levels above the limit value, while CH2O, VOC, PM10 and PM2.5 thresholds were exceeded in 30, 100, 36, and 45% of cases, respectively. Regarding ultrafine parameters, LDSA and PNC ranged from 7.3 to 95.2 μm2/cm3 and from 0.6 to 4.8 × 103/cm3, respectively. Even with no smoking indoors, smokers' bedrooms were found to have significant higher levels of CO, CH2O, PM2.5, PM10 and LDSA than non-smokers' bedrooms, showing the effect of thirdhand smoke, exhalation of pollutants after smoking and infiltration on the degradation of the air quality in the bedroom. A recent new model of real-time monitor was also used for a wide set of IAQ parameters. Its performance to measure PM2.5 and CO2 was assessed, showing its applicability in real conditions. Although often neglected, these micro-environments should be considered in the integrated individual exposure to air pollutants and further studied. MAIN FINDINGS OF THE WORK: Several pollutants (CO2, PM, VOCs and CH2O) exceeded the guidelines during sleep; smokers are exposed to higher levels of CO, CH2O, PM, and LDSA than non-smokers while sleeping.publishe

Calibration and field application of an innovative passive sampler for monitoring groundwater quality

International audienc

Indoor air quality assessment in grocery stores

FCT_UIDB/05608/2020. FCT_UIDP/05608/2020.Indoor Air Quality (IAQ) is a public and occupational health concern, as we are exposed to air pollutants daily given that we spend a great amount of our time in indoor environments. IAQ can be affected by numerous factors, from outdoor pollutants that get indoors through ventilation to building materials, furnishings, and activities carried by the building occupants. Exposure to air pollutants has been linked to a panoply of adverse effects on our health, well-being, and performance. The aim of this study was to assess the IAQ in grocery stores (GSs) in the municipality of Cascais in the Lisbon metropolitan area (Portugal) to characterize the workers’ occupational exposure to air pollutants. The study was conducted in 13 small “family” grocery stores. The IAQ monitoring campaign was conducted using low-cost sensor technologies and focused on several parameters, namely: carbon dioxide (CO2), volatile organic compounds (VOCs), particulate matter (PM10 and PM2.5), temperature (T), relative humidity (RH). Overall, the IAQ of the studied GSs complied with Portuguese legislation, except for PM2.5, where 23% of GSs presented levels above the established limit value. The mean inhaled dose of workers during a workday was estimated to be 157.7 ± 57.2 μg for PM2.5 and 165.8 ± 56.0 μg for PM10. The IAQ assessment allowed the identification of the best strategies to improve worker experience in indoor workplace environments.info:eu-repo/semantics/publishedVersio