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1.
Environ Monit Assess ; 193(4): 240, 2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33791866

RESUMEN

Against the backdrop of the almost total failure of conventional physical fences to prevent deaths due to human-elephant conflict and elephant-train collision, management of the problem requires novel approaches. The elephant is a giant and intelligent animal, who, as has been observed through experience, cannot be effectively confined to an area by physical barriers, most of which are built without even considering long-established elephant passes. Instead, human habitats and facilities, including highways, should be pre-planned following an overall strategy to suitably assign natural resources to each party such that natural habitats are disturbed as little as possible. Hence, we envisage the need for a virtual elephant fence as part of the aforesaid strategy to warn elephants that a certain area is not appropriate for them to be present in or best for the safety of the herd. The present study involved in-depth experimentation to investigate the effects of multiple stimuli on real elephants based on the known elephant responses to such stimuli. The proposed system is an autonomous system that detects the presence of elephants, generates alarms for concerned parties, and coordinatively and tactically repels the animals back to safer areas. Experiment results indicated that the sound of a drone and the sound of tiger growls can both exert a strong deterrent effect on elephants. The sound of bees and the low-frequency burst yielded similar results in terms of encounter and withdrawal reactions. The resulting insights may lay a foundation for a novel approach toward the management of human-elephant conflict and elephant-train collisions.


Asunto(s)
Elefantes , Animales , Conservación de los Recursos Naturales , Ecosistema , Monitoreo del Ambiente , Recursos Naturales
2.
Environ Monit Assess ; 193(4): 241, 2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33791871

RESUMEN

Stormwater runoff is a major concern in urban areas which is mostly the result of vast urbanization. To reduce urban stormwater runoff and improve water quality, low impact development (LID) is used in urban areas. Therefore, it is vital to find the optimal combination of LID controls to achieve maximum reduction in both stormwater runoff and pollutants with optimal cost. In this study, a simulation-optimization model was developed by linking the EPA Storm Water Management Model (SWMM) to the Multi-Objective Particle Swarm Optimization (MOPSO) using MATLAB. The coupled model could carry out multi-objective optimization (MOO) and find potential solutions to the optimization objectives using the SWMM simulation model outputs. The SWMM model was developed using data from the BUNUS catchment in Kuala Lumpur, Malaysia. The total suspended solids (TSS) and total nitrogen (TN) were selected as pollutants to be used in the simulation model. Vegetated swale and rain garden were selected as LID controls for the study area. The LID controls were assigned to the model using the catchment characteristics. The target objectives were to minimize peak stormwater runoff, TSS, and TN with the minimum number of LID controls applications. The LID combination scenarios were also tested in SWMM to identify the best LID types and combination to achieve maximum reduction in both peak runoff and pollutants. This study found that the peak runoff, TSS, and TN were reduced by 13%, 38%, and 24%, respectively. The optimal number of LID controls that could be used at the BUNUS catchment area was also found to be 25.


Asunto(s)
Monitoreo del Ambiente , Lluvia , Malasia , Control de Calidad , Urbanización , Movimientos del Agua
3.
Environ Monit Assess ; 193(5): 242, 2021 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-33818693

RESUMEN

This study projects and models the terrestrial net primary productivity (NPP) considering the representative concentration pathways (RCPs) scenarios of Turkey using remote-sensing-based biogeochemical modelling techniques. Changes in annual NPP between 2000-2010 and 2070-2080 were projected with the biogeochemical ecosystem model NASA-Carnegie Ames Stanford Approach (CASA). A multi-temporal data set, including 16-day MODIS composites with a spatial resolution of 250 m, was used within the CASA model. The 5th Assessment Report (AR5) of the IPCC presented several scenarios for RCPs named RCP 2.6, RCP 4.5, RCP 6.0, and RCP 8.5 that laid the foundation for the future climate projections. The futuristic NPP modelling was based on the assumptions of maintaining CO2 level in the range of 421 to 936 ppm and a rise in temperature from 1.1 to 2.6 °C. The NPP in Turkey averaged 1232 g C m2 year-1 as per the model results. Considering 2000-2010 as the baseline period, the NPP was modelled within the range of 9.6 and 316 g C m2 year-1. Modelled average NPP was 1332.4 g C m2 year-1 per year between 2061 and 2080. The forest productivity was also estimated to be increased up to 113 g C m-2 year-1 under the climate change scenarios. However, there were minor differences in the projected average NPP under the baseline period covering years from 2000 to 2080 from those under RCPs. It appeared that variation in temperature and precipitation as a result of climate change affected the terrestrial NPP. The regional environmental and socio-economic consequences of climate change on diverse landscapes such as Turkey were properly modelled and analysed to understand the spatial variation of climate change impacts on vegetation. Changes in NPP imply that forests in Turkey could be carbon sinks in the future as their current potential that would profile Turkey's climate mitigation. This is one of the pioneering studies to estimate the future changes of regional NPP in Turkey by integrating various spatial inputs and a biogeochemical model.


Asunto(s)
Cambio Climático , Ecosistema , China , Monitoreo del Ambiente , Modelos Teóricos , Turquia
4.
Environ Monit Assess ; 193(5): 246, 2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33821337

RESUMEN

This study aimed to investigate the occurrence of drugs and endocrine disrupters in water supplies and in water for human consumption. Twelve sampling campaigns were carried out during the rainy and dry season at four sampling points in the Bolonha Complex, in the city of Belém, northern region of Brazil: Bolonha reservoir (catchment) and Water Treatment Plant (WTP) Bolonha (filtered water chamber, treated water tank, and washing water from the filters). The determination of the compounds was performed by solid phase extraction followed by gas and liquid chromatography coupled to mass spectrometry. The results confirmed the anthropic influence that the reservoir and WTP-Bolonha have been suffering, as consequence of the discharge of domestic sewage in natura. Among 25 microcontaminants analyzed, 12 were quantified in raw water and 10 in treated water. The antiallergic Loratadine (LRT) was the contaminant that occurred most frequently in all sample points, having been poorly removed (median 12%) in the conventional treatment used. Losartana (LST), 4-octylphenol (4-OP), and Bisphenol A (BPA) also occurred very frequently in raw water with concentrations ranging from 3.7 to 194 ng L-1. Although such contaminants occurred in treated water in concentrations varying from 4.0 to 135 ng L-1, the estimated margin of exposure ranged from 55 to 3333 times which indicates low risk of human exposure to such contaminants through ingestion of treated water.


Asunto(s)
Disruptores Endocrinos , Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Purificación del Agua , Brasil , Disruptores Endocrinos/análisis , Monitoreo del Ambiente , Humanos , Contaminantes Químicos del Agua/análisis
5.
Environ Monit Assess ; 193(5): 243, 2021 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-33821353

RESUMEN

The aim of this study was to assess the genotoxic effects of sediment elutriates of an aquatic ecosystem. Sediment samples were taken from Limache stream, located in central Chile. The tests were carried out on sediment elutriates. Genotoxicity was determined by bioassay with Allium cepa. The percentage of germination, root growth, mitotic index, and frequency of chromosome aberrations were determined. The results show a significant increase in chromosome aberrations and decrease of the mitotic index in Allium cepa in all the sediment elutriates compared to the control. No significant differences were observed in the percentages of germination or root growth among the sediment elutriates. A negative correlation was found between the mitotic index and chromosomal aberrations. In conclusion, genotoxic variables are more sensitive than growth variables. The sediments contain chemical agents in bioavailable concentrations that produce genotoxic effects. Allium cepa test proved to be a sensitive indicator of genotoxic contaminants in sediment elutriates of the Limache stream in central Chile.


Asunto(s)
Allium , Cebollas , Chile , Aberraciones Cromosómicas , Daño del ADN , Ecosistema , Monitoreo del Ambiente , Humanos , Índice Mitótico , Raíces de Plantas , Ríos
6.
Environ Monit Assess ; 193(5): 244, 2021 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-33821354

RESUMEN

Polybrominated diphenyl ethers (PBDEs) have been classified as persistent organic pollutants (POPs) as well as endocrine-disrupting compounds (EDCs). This study determined the concentrations of six PBDE congeners (BDE 47, BDE 99, BDE 100, BDE 153, BDE 154, and BDE 183) in water and sediment samples from open city drains, in the Makurdi Metropolitan Area, North Central Nigeria, using gas chromatogragh-mass spectrometer. These congeners are components of the penta- and octa-BDE formulations that have been banned by the European Union. The samples were collected from the drains, bi-monthly, for 1 year across dry and wet seasons. All the congeners considered were found to be present in both water and sediment. The levels of Σ6PBDEs in water ranged from 0.05 to 0.28 ng L-1 during dry season and 0.02 to 0.36 ng L-1 during wet season, while their levels in sediment during dry and wet seasons ranged from 3.22 to 26.26 ng g-1 and 7.51 to 27.41 ng g-1, respectively. The percentage recoveries from solid phase and Soxhlet extractions ranged from 69 to 104% and 70 to 112%, respectively. It was concluded that the presence of all the congeners in both water and sediment posed a pollution risk to the river in which the drains discharge and require further monitoring and necessary preventive measures.


Asunto(s)
Éteres Difenilos Halogenados , Contaminantes Químicos del Agua , China , Ciudades , Monitoreo del Ambiente , Sedimentos Geológicos , Éteres Difenilos Halogenados/análisis , Nigeria , Agua , Contaminantes Químicos del Agua/análisis
7.
Environ Monit Assess ; 193(5): 245, 2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33821384

RESUMEN

Studies to assess variability factors of heavy metals in soils are essential to understand their behavior in the environment and for the assessment of contaminated areas. In this context, this research aimed to study the factors that influence the variability of heavy metal levels and their bioavailability in pasture areas in the Alturas de Nazareno region, Mayabeque, Cuba, as well as the transfer to plants. Forty-five points were distributed in a natural pasture and at two depths (0-20 and 20-40 cm) as a function of relief and soil type. Pseudo-total heavy metal contents were determined according to method 3051A of USEPA, geochemical fractionation according to the Community Bureau of Reference method, and plant digestion according to method 3052 of USEPA. Soil samples were separated into two groups, according to cluster analysis. The type of soil associated with the pH and Ca attributes were the factors that most influenced the variability of the total and bioavailable levels of metals in natural pasture soils in the region of Alturas de Nazareno. Group 1 showed the lowest heavy metal contents and the highest pH and calcium values, which were predominantly associated with carbonate soils. Group 2 had the highest contents of heavy metals and Fe, corresponding mainly to the soil Ferralítico Rojo. The concentration of metals in plants was directly related to their bioavailable content in the soil, where G2 represents the group with the highest risk of transferring metals to the food chain.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Cuba , Monitoreo del Ambiente , Metales Pesados/análisis , Suelo , Contaminantes del Suelo/análisis
8.
J Occup Environ Hyg ; 18(sup1): S35-S43, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33822693

RESUMEN

RESUMENLas mascarillas respiratorias autofiltrantes (filtering facepiece respirators, FFR) N95 certificadas por el Instituto Nacional de Seguridad y Salud Laborales (National Institute for Occupational Safety and Health, NIOSH) se utilizan en los centros de atención sanatoria como medida de control para mitigar las exposiciones a partículas atmosféricas infecciosas. Cuando la superficie externa de una FFR se contamina, supone un riesgo de transmisión para el usuario. La guía de los Centros para el Control y Prevención de Enfermedades (Centers for Disease Control and Prevention, CDC) recomienda que el personal sanitario retire las FFR agarrando las tiras en la parte posterior de la cabeza para evitar el contacto con la superficie posiblemente contaminada. Al parecer, la adherencia a la técnica de retirada adecuada es baja, debido a numerosos factores que incluyen la dificultad para ubicar y agarrar las tiras. En este estudio se compara el impacto de lengüetas ubicadas en las tiras de la FFR con el de mascarillas comparativas (sin lengüetas) sobre la retirada adecuada, la facilidad de uso, la comodidad y la reducción de la transmisión de la contaminación al usuario. El uso de un agente fluorescente como rastreador de contactos para explorar la contaminación de las FFR en manos y áreas de la cabeza de 20 sujetos humanos demostró que no hubo diferencia entre las tiras de la FFR con lengüetas y las mascarillas comparativas en el sentido de estimular la retirada adecuada de las mismas (p = 0.48), pero la hizo más fácil (p = 0.04), según indican siete de ocho sujetos que usaron las lengüetas. Siete de 20 sujetos opinaron que las FFR con lengüetas son más fáciles de retirar, mientras que solo dos de 20 sujetos indicaron que las FFR sin lengüetas son más fáciles de retirar. La incomodidad no fue un factor relevante para ninguno de los tipos de tiras de las FFR. Al retirar una FFR con las manos contaminadas, el uso de lengüetas redujo de forma importante la cantidad del rastreador de contactos transferida en comparación con las tiras sin lengüetas (p = 0.012). Las FFR con lengüetas en las tiras están asociadas con la facilidad de la retirada y una transferencia notablemente menor del rastreador de contactos fluorescente.

9.
J Occup Environ Hyg ; 18(sup1): S53-S60, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33822695

RESUMEN

RESUMENCuando se retira el equipo de protección personal (EPP), los patógenos pueden transferirse desde el EPP al cuerpo de los trabajadores de la salud, poniendo en riesgo de exposición e infección tanto a ellos mismos como a sus pacientes. Entre marzo de 2017 y abril de 2018 se observaron las prácticas de retirada del EPP del personal sanitario que atendía pacientes con infecciones respiratorias virales en un hospital de atención de enfermedades agudas. Un observador capacitado registró el desempeño del personal sanitario cuando retiraba el EPP dentro de las habitaciones de los pacientes, utilizando una lista de verificación predefinida basada en las directrices de los Centros para el Control y Prevención de Enfermedades (Centers for Disease Control and Prevention, CDC). Se observaron 162 prácticas de retirada durante el cuidado de 52 pacientes infectados con patógenos virales respiratorios. De estos 52 pacientes, 30 estaban en aislamiento por gota y contacto, 21 en aislamiento por gota y uno en aislamiento de contacto. En general, en 90% de los casos la retirada del EPP observada se realizó de manera incorrecta, ya sea en cuanto a la secuencia de retirada, la técnica de retirada o el uso del EPP apropiado. Los errores más comunes consistieron en quitarse la bata por adelante, retirar la pantalla facial de la mascarilla y tocar superficies y EPP potencialmente contaminados durante el proceso. Las desviaciones del protocolo recomendado para retirar el EPP son comunes y pueden aumentar el potencial de contaminación de la ropa o la piel del personal sanitario después de proporcionar atención. Existe una clara necesidad de cambiar el enfoque utilizado para capacitar al personal en las prácticas de retirada del EPP.

10.
Rev. cuba. anestesiol. reanim ; 20(1): e701, ene.-abr. 2021.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1156367

RESUMEN

RESUMEN Introducción: La convivencia con la infección por COVID-19 en Cuba supone un reto actual de adaptación a todos los entornos hospitalarios y de salud, creación de protocolos y nuevos modelos de asistencia. La intervención sobre la vía aérea en sus diferentes formas, conlleva un riesgo de contaminación al personal de la salud. Objetivo: Describir las consideraciones anestésicas en los procedimientos laparoscópicos y endoscópicos durante la pandemia COVID-19. Métodos: Se realizó un estudio cualitativo, de investigación-acción, apoyado en el análisis de documentos y la observación participante de las acciones tomadas en el Centro Nacional de Cirugía de Mínimo Acceso en el curso de los cuatro meses transcurridos a partir de que se identificara el primer caso de COVID-19 en Cuba. Resultados: Se establecieron las recomendaciones anestésicas para el procedimiento de actuación durante la COVID-19 en el Centro Nacional de Cirugía de Mínimo Acceso, que dictan las acciones para el tratamiento de los pacientes y la protección de los trabajadores. Esto posibilita mantener la calidad de los servicios médico quirúrgicos en estos escenarios de riesgo. Conclusiones: La evaluación y tratamiento anestésico estandarizado de los pacientes ante el brote de COVID-19 y en la fase poscovid permite optimizar la seguridad del paciente y el personal sanitario. Es importante el cumplimiento de los protocolos dirigidos hacia el control estricto de la parada quirúrgica, uso adecuado de los equipos de protección personal, disminución de los aerosoles con métodos de barrera y la desinfección del salón y equipos al concluir la intervención.


ABSTRACT Introduction: Coexistence with COVID-19 infection in Cuba is a current challenge of adaptation to all hospital and health settings, creation of protocols and new models of care. The airway approach in its different forms represents a risk of contamination of the health personnel. Objective: To describe the anesthetic considerations in laparoscopic and endoscopic procedures during the COVID-19 pandemic. Methods: A qualitative, action-research study was carried out, supported by the analysis of documents and participant observation of the actions taken in the National Center for Minimally-Invasive Surgery in the course of four months after the first case of COVID-19 was identified in Cuba. Results: Anesthetic recommendations were established for the action procedure during COVID-19 in the National Center for Minimally-Invasive Surgery, which dictate the actions for the treatment of patients and the protection of workers. This makes it possible to maintain the quality of surgical medical services in these risk settings. Conclusions: Assessment and standardized anesthetic treatment of patients in the face of the COVID-19 outbreak and in the post-COVID phase allows optimizing the safety of the patient and the healthcare personnel. It is important to comply with the protocols aimed at controlling strictly the surgical setting, proper use of personal protective equipment, reduction of aerosols with barrier methods, and disinfection of the room and equipment at the conclusion of the intervention.

11.
Environ Monit Assess ; 193(5): 247, 2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33822279

RESUMEN

The study presents the characterization of the water quality of the Corumbá IV reservoir in the State of Goiás, in the Brazilian Cerrado biome, based on data from the operation period between 2007 and 2017. Few are known about the temporal and spatial variations in the water quality of the reservoir. Up to now, the water quality has been analyzed only from the point of view of compliance with the limits required by Brazilian environmental legislation. Therefore, the integrated analysis of water quality parameters and water body dynamics may bring important information to support decision-making in reservoir management. An exploratory analysis of the limnological data series provided by the company in charge of the hydroelectric plant was then carried out. Univariate and multivariate statistical techniques were applied to analyze the data period from 2007 to 2017. The results identify four distinct limnological phases representing the transition of the environment. The first phase (2007 to 2009) characterized by the decomposition of the flooded vegetal organic matter and subsequent phases, after 8 years (2010 to 2017), have featured the transition process from the lotic condition to the consolidation of the lentic environment. The spatial analysis of the results demonstrates that tributaries influence the water quality of the reservoir differently, probably due to the different impacts suffered in the sub-basins (e.g., sewage discharges; runoff). Although it is possible to evidence the impact of anthropic activities on water quality, the reservoir still presents characteristics of an environment with low trophic status.


Asunto(s)
Monitoreo del Ambiente , Calidad del Agua , Brasil , Ecosistema , Ríos , Análisis Espacio-Temporal
12.
Environ Monit Assess ; 193(5): 248, 2021 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-33825990

RESUMEN

Flood is considered to be one of the most destructive natural disasters. It is important to detect the flood-affected area in a reasonable time. In March 2019, a severe flood occurred in the north of Iran and lasted for 2 months. In the present paper, this flood event has been monitored by Sentinel-1 images. The Otsu thresholding algorithm has been applied to separate flooded areas from remaining land covers. The threshold value of -14.9 dB was derived and applied to each scene to delineate flooded areas. There was high variability of the inundated area; however, the presented threshold correctly represented the variation of the flood. The resultant maps were further verified by independent datasets. The overall accuracies were higher than 90%, confirming the applicability of the Otsu automatic thresholding method in flood mapping. The automatic approach is efficient in rapid fold mapping across complex landscapes.


Asunto(s)
Inundaciones , Ríos , Monitoreo del Ambiente , Irán
13.
Environ Monit Assess ; 193(5): 249, 2021 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-33829338

RESUMEN

This study presents the development of an analytical method for the simultaneous determination of multiclass illicit drugs (cocainoids, opiates, amphetamines, and cannabinoids) and psychoactive pharmaceuticals (anxiolytics, hypnotics, antipsychotics, antidepressants, and antiparkinsonian), in municipal wastewater. The analytical method was validated in terms of specificity, linearity, precision, and accuracy. The recoveries (%) for the majority of the analytes ranged between 70 and 120%, while the method showed good repeatability (2.4-29.2%). The limits of detection (LOD) of the method ranged between 0.8 and 9.4 ng L-1. The method was implemented on influent and effluent samples from Thessaloniki (N. Greece) wastewater treatment plant (WWTP), and it revealed the daily presence of benzoylecgonine (BEG) (84.0-202.2 ng L-1), methadone (12.3-17.5 ng L-1), 11-Nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) (80.3-171.9 ng L-1), morphine (144.2-264.3 ng L-1), and 6-monoacetylmorphine (6-MAM) (5.8-12.0 ng L-1) in the influent samples of WWTP. Clozapine (101.6-315.5 ng L-1), quetiapine (33.5-109.7 ng L-1), and fluoxetine (20.9-124.4 ng L-1) were pharmaceutical psychotics with the highest concentration in the influents. Back calculation estimated that the daily consumption of cocaine, heroin, cannabis, and methadone was 36-95, 86-164, 2300-5400, and 8-12 mg day-1 per 1000 inhabitants, respectively. The consumption was estimated between 7-16 and 15 mg day-1 per 1000 inhabitants for methyl diethanolamine (MDEA) and 3,4-methylenedioxymethamphetamine (MDMA), respectively.


Asunto(s)
Drogas Ilícitas , Contaminantes Químicos del Agua , Cromatografía Liquida , Monitoreo del Ambiente , Grecia , Extracción en Fase Sólida , Espectrometría de Masas en Tándem , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis
14.
Environ Monit Assess ; 193(5): 250, 2021 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-33829339

RESUMEN

Chlorinated paraffins (CPs) are anthropogenic pollutants of growing environmental concern. These highly complex mixtures of thousands of homologs and congeners are usually applied as additives in lubricants or as flame retardants and plasticizers in polymers and paints. Recent studies indicated the presence of high amounts of CPs in the kitchen environment whose sources could not be unequivocally identified. One option was the use of CPs as or in lubricants of hinges. To test this hypothesis, we performed wipe tests on lubricants on 29 hinges of different types of kitchen appliances (refrigerators, baking ovens, dishwashers, freezers, microwave oven, pasta machine, food processor, steam cooker) and analyzed them for short-chain CPs (SCCPs) and medium-chain CPs (MCCPs). CPs were detected in 21 samples (72%). Per wipe, SCCP concentrations ranged between 0.02 and 10 µg (median 0.23 µg), while MCCPs ranged from 0.09 to 750 µg (median 1.0 µg). Highest MCCP amounts (380 and 750 µg per wipe, respectively) were determined in new and unused appliances. A medium correlation between SCCP content and appliance age was observed, but no additional statistic correlation between SCCP/MCCP amount and appliance type or manufacturer could be observed. CPs released from hinges by volatilization, abrasion, and cleaning processes could enter the environment and come in contact with persons living in the corresponding households.


Asunto(s)
Contaminantes Ambientales , Retardadores de Llama , Hidrocarburos Clorados , China , Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Hidrocarburos Clorados/análisis , Parafina/análisis
15.
Artículo en Inglés | MEDLINE | ID: mdl-33800440

RESUMEN

To control the spread of coronavirus disease (COVID-19), Saudi Arabia's government imposed a strict lockdown during March-July 2020. As a result, the public was confined to indoors, and most of their daily activities were happening in their indoor places, which might have resulted in lower indoor environment quality. Polycyclic aromatic hydrocarbons (PAHs) were analyzed in household dust (n = 40) collected from different residential districts of Jeddah, Saudi Arabia, during the lockdown period. PAHs' levels were two folds higher than the previously reported PAHs in indoor dust from this region. We detected low molecular weight (LMW) with two to four aromatic ring PAHs in all the samples with a significant contribution from Phenanthrene (Phe), present at an average concentration of 1590 ng/g of dust. Although high molecular weight (HMW) (5-6 aromatic ring) PAHs were detected at lower concentrations than LMW PAHs, however, they contributed >90% in the carcinogenic index of PAHs. The estimated daily intake (EDI) of specific PAHs was above the reference dose (RfD) for young children in high-end exposure and the calculated Incremental Lifetime Cancer Risk (ILCR) was >1.00 × 10-4 for both Saudi adults and young children. The study highlighted that indoor pollution has increased significantly during lockdown due to the increased indoor activities and inversely affect human health. This study also warrants to conduct more studies involving different chemicals to understand the indoor environment quality during strict lockdown conditions.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Coronavirus , Hidrocarburos Policíclicos Aromáticos , Adulto , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Niño , Preescolar , Control de Enfermedades Transmisibles , Polvo/análisis , Monitoreo del Ambiente , Humanos , Pandemias , Hidrocarburos Policíclicos Aromáticos/análisis , Medición de Riesgo , Arabia Saudita/epidemiología
16.
Artículo en Inglés | MEDLINE | ID: mdl-33805343

RESUMEN

In early 2020 from April to early June, the metropolitan area of Sydney as well as the rest of New South Wales (NSW, Australia) experienced a period of lockdown to prevent the spread of COVID-19 virus in the community. The effect of reducing anthropogenic activities including transportation had an impact on the urban environment in terms of air quality which is shown to have improved for a number of pollutants, such as Nitrogen Dioxides (NO2) and Carbon Monoxide (CO), based on monitoring data on the ground and from a satellite. In addition to primary pollutants CO and NOx emitted from mobile sources, PM2.5 (primary and secondary) and secondary Ozone (O3) during the lockdown period will also be analyzed using both statistical methods on air quality data and the modelling method with emission and meteorological data input to an air quality model. By estimating the decrease in traffic volume in the Sydney region, the corresponding decrease in emission input to the Weather Research and Forecasting-Community Multiscale Air Quality Modelling System (WRF-CMAQ) air quality model is then used to estimate the effect of lockdown on the air quality especially CO, NO2, O3, and PM2.5 in the Greater Metropolitan Region (GMR) of Sydney. The results from both statistical and modelling methods show that NO2, CO, and PM2.5 levels decreased during the lockdown, but O3 instead increased. However, the change in the concentration levels are small considering the large reduction of ~30% in traffic volume.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Australia , Control de Enfermedades Transmisibles , Monitoreo del Ambiente , Humanos , Nueva Gales del Sur , Pandemias , Material Particulado/análisis
17.
Artículo en Inglés | MEDLINE | ID: mdl-33806039

RESUMEN

The novel coronavirus (COVID-19) pandemic has provided a distinct opportunity to explore the mechanisms by which human activities affect air quality and pollution emissions. We conduct a quasi-difference-in-differences (DID) analysis of the impacts of lockdown measures on air pollution during the first wave of the COVID-19 pandemic in China. Our study covers 367 cities from the beginning of the lockdown on 23 January 2020 until April 22, two weeks after the lockdown in the epicenter was lifted. Static and dynamic analysis of the average treatment effects on the treated is conducted for the air quality index (AQI) and six criteria pollutants. The results indicate that, first, on average, the AQI decreased by about 7%. However, it was still over the threshold set by the World Health Organization. Second, we detect heterogeneous changes in the level of different pollutants, which suggests heterogeneous impacts of the lockdown on human activities: carbon monoxide (CO) had the biggest drop, about 30%, and nitrogen dioxide (NO2) had the second-biggest drop, 20%. In contrast, ozone (O3) increased by 3.74% due to the changes in the NOx/VOCs caused by the decrease in NOx, the decrease of O3 titration, and particulate matter concentration. Third, air pollution levels rebounded immediately after the number of infections dropped, which indicates a swift recovery of human activities. This study provides insights into the implementation of environmental policies in China and other developing countries.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China/epidemiología , Ciudades , Control de Enfermedades Transmisibles , Monitoreo del Ambiente , Humanos , Pandemias , Material Particulado/análisis
18.
Artículo en Inglés | MEDLINE | ID: mdl-33808577

RESUMEN

Over the past decades, urbanization and industrialization have led to a change in air quality, bringing researchers to a full realization of the damaging effects of human activities on the environment. This study focused on describing air quality during the initial phase of the Novel Coronavirus disease (COVID-19) pandemic (since there were fewer anthropogenic activities) in 10 Chinese mega-cities. Using the independent t-test, the means of air quality index (AQI) scores and individual air pollutants concentration during the outbreak were compared with the means before the outbreak. Cohen's d was estimated to quantify how much difference was observed. Based on the AQI score, the air quality in these 10 cities ranged from excellent (Shenzhen) to light pollution (Xi'an) with 44.8 µg m-3 and 119.7 µg m-3, respectively. In comparison to the 2019 air quality, Guangzhou and Wuhan noted major differences in air quality during the outbreak. Indicators of traffic pollution, particularly NO2, were significantly lower during the outbreak in all cities. Particulate matter pollution varied, with some cities observing lower concentrations and other higher concentrations during the outbreak. There was a significant decrease in air pollution levels during the outbreak. More researchers should observe changes in air quality during peculiar or major events. Implementation of stringent regulation on vehicle use should be considered in mega-cities. Relevant findings should be employed in emphasizing the detrimental effects of anthropogenic activities and support the need for stringent emission control regulations.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Coronavirus , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China/epidemiología , Ciudades , Monitoreo del Ambiente , Humanos , Material Particulado/análisis
19.
Ecotoxicol Environ Saf ; 214: 112095, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33667735

RESUMEN

In this study, urban stream sediment samples were collected in the Suzhou Industrial Park (SIP), one of the earliest national demonstration eco-industrial parks of China. PAHs were analyzed in these sediments, and concentrations of total PAHs were 180-81,000 ng g-1 (5700 ± 14,000 ng g-1). Medium molecular weight (4- ring) PAHs were predominant (42 ± 12%), followed by high molecular weight (5- and 6- ring) PAHs (31 ± 10%). No correlation was found between concentrations of PAHs and land uses of SIP in this study. Diagnostic ratios and a positive matrix factorization (PMF) model indicated that coal/biomass combustion might be the primary PAH source (61%), followed by non-combustion sources (21%) and vehicular emission (18%). According to the spatial analysis, PAHs in the sediments of SIP might be mainly associated with the coal/biomass combustion in the northeast industrial zone. Residential & commercial activities seem not to be the major causes of PAH contamination. Total PAH toxic equivalent concentrations, effect range low/effect range median values, and mean effects range-median quotient all showed that PAHs were present at a low toxicity risk level in most regions of the SIP. However, vigilance is required at some sampling sites with extremely high PAH concentrations or high mean effects range-median quotient.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis , China , Carbón Mineral/análisis , Monitoreo del Ambiente , Sedimentos Geológicos , Industrias , Medición de Riesgo , Ríos , Emisiones de Vehículos/análisis
20.
Ecotoxicol Environ Saf ; 214: 112094, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33677382

RESUMEN

Honey has multifaceted nutritional and medicinal values; however, its quality is hinged on the floral origin of the nectar. Taking advantage of the large areas that they cover; honeybees are often used as bioindicators of environmental contamination. The focus of the present paper was to examine the quality of honey from within the vicinity of an abandoned pesticide store in Masindi District in western Uganda. Surficial soils (<20 cm depths) and honey samples were collected from within the vicinity of the abandoned pesticide store and analysed for organochlorine pesticide (OCP) residues using gas chromatograph coupled to an electron capture detector (GC-ECD). The mean level of ∑DDTs in all the soil samples was 503.6 µg/kg dry weight (d.w). ∑DDTs contributed 92.2% to the ∑OCPs contamination loads in the soil samples, and others (lindane, aldrin, dieldrin, and endosulfans) contributed only 7.8%. Ratio (p, p'-DDE+p, p'-DDD)/p, p'-DDT of 1.54 suggested historical DDT input in the area. In all the honey samples, the mean level of ∑DDTs was 20.9 µg/kg. ∑DDTs contributed 43.3% to ∑OCPs contamination loads in the honey samples, followed by lindane (29.8%), endosulfans (23.6%) and dieldrin (3.2%), with corresponding mean levels of 14.4, 11.4 and 1.55 µg/kg, respectively. Reproductive risk assessment was done based on the hazard quotient (HQ) and hazard index (HI) procedure. In our study, the calculated HIs for adults (102.38), and children (90.33) suggested high potential health risks to the honey consumers. Lindane, endosulfan and p, p'-DDD detected in the honey samples at levels exceeding the acute reference dose (ARfD) are known risk factors for spontaneous abortion, reduced implantation, menstrual cycle shortening, impaired semen quality, and prostate cancer in exposed individuals and experimental animal models.


Asunto(s)
Exposición Dietética/estadística & datos numéricos , Miel/análisis , Hidrocarburos Clorados/análisis , Residuos de Plaguicidas/análisis , Adulto , Aldrín/análisis , Animales , Niño , DDT/análisis , Diclorodifenil Dicloroetileno/análisis , Dieldrín/análisis , Endosulfano/análisis , Biomarcadores Ambientales , Monitoreo del Ambiente/métodos , Femenino , Hexaclorociclohexano/análisis , Humanos , Masculino , Plaguicidas/análisis , Salud Reproductiva , Análisis de Semen , Suelo , Uganda
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