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1.
Food Chem ; 336: 127725, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32768912

RESUMEN

Thirty one samples from different macroalgae species have been studied to determine the influence of several parameters such as the harvesting season, the geographical origin, the species or a pretreatment procedure on their volatile composition. A Multiple Head Space Sorptive Extraction methodology coupled to Gas Chromatography with Mass Spectrometry Detection (MHSSE-GC-MS) has been used to analyze 44 volatile compounds that can be found in the different samples. Of all the factors, the collection season proved to be the most influential, followed by origin with significantly lower volatile compounds concentrations found in the samples collected in spring and in southern Spain. A Principal Component Analysis showed that beta ionone, benzaldehyde, 6-methyl-5-hepten-2-one, together with some acids were the most strongly affected by the season, with highest values in those samples that had been collected in the autumn. On the other hand, the pretreatment (raw, salting or dehydration) proved to have a low influence.


Asunto(s)
Algas Marinas/química , Compuestos Orgánicos Volátiles/análisis , Análisis de Varianza , Cromatografía de Gases y Espectrometría de Masas/métodos , Análisis de Componente Principal , Estaciones del Año , Algas Marinas/metabolismo , España
2.
Food Chem ; 336: 127744, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32781352

RESUMEN

Cardoon (Cynara cardunculus L.) bracts were collected at different maturation stages to investigate seasonal changes in the phenolic compounds profile and in vitro bioactivities. Among the 12 phenolic compounds tentatively identified, 3,5-O-dicaffeoylquinic acid (21.83 mg/g extract) and apigenin-7-O-glucuronide (10.6 mg/g extract) were the most abundant. Immature bracts (C1: principal growth stage (PGS) 5) had the highest phenolic compounds content, and anti-inflammatory (IC50 = 72 µg/mL) and cytotoxic (GI50 of 30-79 µg/mL) activities. Moreover, extract C1 inhibited efficiently the formation of thiobarbituric acid reactive substances (TBARS; IC50 = 26.8 µg/mL), while extract C8 (PGS 8/9) was more effective against oxidative haemolysis (IC50 38 and 75 µg/mL). The highest antibacterial and antifungal activities were attributed to samples C1 and C6 (PGS 7/8) and samples C2 (PGS 5/6) and C4 (PGS 6/7), respectively. Overall, the obtained results suggest the seasonal changes of polyphenolic composition and bioactivity of cardoon bracts of variable maturity.


Asunto(s)
Cynara/química , Fenoles/química , Animales , Antiinfecciosos/química , Antiinfecciosos/farmacología , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antioxidantes/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cynara/crecimiento & desarrollo , Cynara/metabolismo , Hongos/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Óxido Nítrico/metabolismo , Fenoles/análisis , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Células RAW 264.7 , Estaciones del Año
3.
Chemosphere ; 262: 127767, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32763576

RESUMEN

This study aimed to determine the spatial distribution of PM2.5 and PM10 collected in four regions (North, Central, South and East Coast) of Peninsular Malaysia during the southwest monsoon. Concurrent measurements of PM2.5 and PM10 were performed using a high volume sampler (HVS) for 24 h (August to September 2018) collecting a total of 104 samples. All samples were then analysed for water soluble inorganic ions (WSII) using ion chromatography, trace metals using inductively coupled plasma-mass spectroscopy (ICP-MS) and polycyclic aromatic hydrocarbon (PAHs) using gas chromatography-mass spectroscopy (GC-MS). The results showed that the highest average PM2.5 concentration during the sampling campaign was in the North region (33.2 ± 5.3 µg m-3) while for PM10 the highest was in the Central region (38.6 ± 7.70 µg m-3). WSII recorded contributions of 22% for PM2.5 and 20% for PM10 mass, with SO42- the most abundant species with average concentrations of 1.83 ± 0.42 µg m-3 (PM2.5) and 2.19 ± 0.27 µg m-3 (PM10). Using a Positive Matrix Factorization (PMF) model, soil fertilizer (23%) was identified as the major source of PM2.5 while industrial activity (25%) was identified as the major source of PM10. Overall, the studied metals had hazard quotients (HQ) value of <1 indicating a very low risk of non-carcinogenic elements while the highest excess lifetime cancer risk (ELCR) was recorded for Cr VI in the South region with values of 8.4E-06 (PM2.5) and 6.6E-05 (PM10). The incremental lifetime cancer risk (ILCR) calculated from the PAH concentrations was within the acceptable range for all regions.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Metales/análisis , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Industrias , Malasia , Tamaño de la Partícula , Estaciones del Año , Análisis Espacial , Oligoelementos/análisis
4.
J Environ Sci (China) ; 99: 72-79, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33183718

RESUMEN

This study encompassed the regular observation of nine polycyclic aromatic hydrocarbons (PAHs) and three nitro-PAHs (NPAHs) in particulate matter (PM) in Shanghai in summer and winter from 2010 to 2018. The results showed that the mean concentrations of Æ©PAHs in summer decreased by 24.7% in 2013 and 18.1% in 2017 but increased by 10.2% in 2015 compared to the data in 2010. However, the mean concentrations of Æ©PAHs in winter decreased by 39.7% from 2010 (12.8 ± 4.55 ng/m3) to 2018 (7.72 ± 3.33 ng/m3), and the mean concentrations of 1-nitropyrene in winter decreased by 79.0% from 2010 (42.3 ± 16.1 pg/m3) to 2018 (8.90 ± 2.09 pg/m3). Correlation analysis with meteorological conditions revealed that the PAH and NPAH concentrations were both influenced by ambient temperature. The diagnostic ratios of PAHs and factor analysis showed that they were mainly affected by traffic emissions with some coal and/or biomass combustion. The ratio of 2-nitrofluoranthene to 2-nitropyrene was near 10, which indicated that the OH radical-initiated reaction was the main pathway leading to their secondary formation. Moreover, backward trajectories revealed different air mass routes in each sampling period, indicating a high possibility of source effects from the northern area in winter in addition to local and surrounding influences. Meanwhile, the mean total benzo[a]pyrene-equivalent concentrations in Shanghai in winter decreased by 50.8% from 2010 (1860 ± 645 pg/m3) to 2018 (916 ± 363 pg/m3). These results indicated the positive effects of the various policies and regulations issued by Chinese authorities.


Asunto(s)
Contaminantes Atmosféricos , Hidrocarburos Policíclicos Aromáticos , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Estaciones del Año
5.
Sci Total Environ ; 752: 141846, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32892045

RESUMEN

This paper examines seasonal variations in faecal contamination of drinking water sources in the Jirapa and Kassena-Nankana Municipalities of Ghana. Data collection involved a survey of 568 households, testing of faecal coliform concentrations in drinking water source samples (141 in the rainy season, 128 in the dry season), in-depth interviews with key water stakeholders, and field observation to identify sources of faecal contamination. From the water quality testing, faecal coliforms were detected in all source types, including 'treated' pipe-borne water. Contamination was significantly higher in the rainy season than in the dry season (P < 0.05) with 51.8% of water samples in the rainy season and 27.3% in the dry season failing to meet the World Health Organisation and Ghana Standard Authority guideline on faecal coliform concentrations in drinking water sources. The proportion of population at risk of faecal contamination in the rainy season was 41.5% compared to 33.1% in the dry season. We argue that in Ghana and Sub-Saharan Africa at large, water surveillance agencies risk underestimating population exposed to faecal contamination through drinking water sources if monitoring is only done in the dry season. To avoid this, we recommend seasonal monitoring of faecal concentration in drinking water sources. However, in periods of limited resources, monitoring is most appropriate in the rainy season when the risk of contamination is high.


Asunto(s)
Agua Potable , Ciudades , Agua Potable/análisis , Ghana , Estaciones del Año , Microbiología del Agua , Calidad del Agua , Abastecimiento de Agua
6.
Sci Total Environ ; 753: 141903, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-32896736

RESUMEN

Biogenic aerosols such as airborne grass pollen affect the public health badly by putting additional distress on people already suffering from cardiovascular and respiratory diseases. In Belgium, daily airborne pollen concentrations are monitored offline at a few sites only, hampering the timely coverage of the country and short-term forecasts. Here we apply the Chemistry Transport Model SILAM to the Belgian territory to model the spatio-temporal airborne grass pollen levels near the surface based on bottom-up inventories of grass pollen emissions updated with the Copernicus land monitoring Service grassland map of 2015. Transport of aerosols in SILAM is driven by ECMWF ERA5 meteorological data. The emitted grass pollen amounts in SILAM are computed by the multiplication of the grass pollen source map with the release rate determined by the seasonal shape production curve during the grass flowering period. The onset and offset of this period follow a location-dependent prescribed calendar days. Here we optimize the grass pollen seasonal start and end in SILAM by comparing a 2008-2018 time series of daily airborne grass pollen concentrations from the Belgian aerobiological surveillance network with the simulations. The effect of the spatial distribution of grass pollen sources is quantified by constructing pollen source-receptor relations using model simulations with varying grass pollen emissions in five areas of the model domain as input. Up to 33% of the airborne grass pollen in one area was transport from others areas inside Belgium. Adjusting the start and end of the grass pollen season improved the model performance substantially by almost doubling the correlation with local observations. By introducing the temporal scaling of the inter-seasonal pollen amounts in the model, an additional R2 increase up to 22% was obtained. Further improvements can be made by including more detailed grass pollen sources and more dynamic start and end dates of the pollen season.


Asunto(s)
Alérgenos , Polen , Bélgica , Humanos , Poaceae , Estaciones del Año
7.
Food Chem ; 337: 127690, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32795853

RESUMEN

Climate and feeding influence the composition of bovine milk, which is further affected by thermal treatment inducing oxidation and Maillard reactions. This study aimed to evaluate season- and processing-related changes in the modified proteome of milk from two different feeding systems. Therefore, tryptic digests of regular and hay milk were analyzed by targeting 26 non-enzymatic modifications using LC-MS. Forty-five glycated, 48 advanced glycation endproduct (AGE-) modified, and 20 oxidized/carbonylated peptides representing 44 proteins were identified with lactosylation, formyllysine, and carboxymethyllysine being most common. The numbers and quantities of glycation- and oxidation-related modifications were similar between regular and hay milk and among seasons. The effects of pasteurization and ultra-high temperature (UHT) treatment were comparable for both milk types. In particular UHT treatment increased the numbers of identified modifications and the relative quantities of lactosylated peptides. The number of identified AGE-modified and oxidized residues increased slightly after UHT-treatment, but the contents were stable.


Asunto(s)
Proteínas de la Leche/química , Pasteurización , Estaciones del Año , Animales , Bovinos , Productos Finales de Glicación Avanzada/química , Glicosilación , Calor , Lisina/análogos & derivados , Lisina/química , Reacción de Maillard , Oxidación-Reducción
8.
Sci Total Environ ; 750: 141686, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32861075

RESUMEN

The prediction of the occurrence of infectious diseases is of crucial importance for public health, as clearly seen in the ongoing COVID-19 pandemic. Here, we analyze the relationship between the occurrence of a winter low-pressure weather regime - Cyprus Lows - and the seasonal Influenza in the Eastern Mediterranean. We find that the weekly occurrence of Cyprus Lows is significantly correlated with clinical seasonal Influenza in Israel in recent years (R = 0.91; p < .05). This result remains robust when considering a complementary analysis based on Google Trends data for Israel, the Palestinian Authority and Jordan. The weekly occurrence of Cyprus Lows precedes the onset and maximum of Influenza occurrence by about one to two weeks (R = 0.88; p < .05 for the maximum occurrence), and closely follows their timing in eight out of ten years (2008-2017). Since weather regimes such as Cyprus Lows are more robustly predicted in weather and climate models than individual climate variables, we conclude that the weather regime approach can be used to develop tools for estimating the compatibility of the transmission environment for Influenza occurrence in a warming world. Furthermore, this approach may be applied to other regions and climate sensitive diseases. This study is a new cross-border inter-disciplinary regional collaboration for appropriate adaptation to climate change in the Eastern Mediterranean.


Asunto(s)
Infecciones por Coronavirus , Gripe Humana , Pandemias , Neumonía Viral , Betacoronavirus , Chipre/epidemiología , Humanos , Gripe Humana/epidemiología , Israel/epidemiología , Jordania , Estaciones del Año , Tiempo (Meteorología)
9.
Sci Total Environ ; 751: 141601, 2021 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-32871313

RESUMEN

Temporal and spatial heterogeneity in the distribution of cladocerans in lakes could be caused by abiotic (wind, water currents) and biotic factors (reproduction, food resources, predation). Diel horizontal and vertical distribution of cladoceran assemblages was studied in two deep lakes (Milada and Most Lakes, Czech Republic) in early (June) and late (September) summer. The objective was to study diel vertical migration (DVM) and diel horizontal migration (DHM) of cladocerans under conditions of different macrophyte cover in littoral areas (rich in Milada Lake, poor in Most Lake) and fish assemblages (non-specialised planktivorous species in Milada Lake, and abundant planktivorous fish - maraena whitefish, Coregonus maraena - in open water habitats in Most Lake). Temporal variations in cladoceran assemblages were reported in both lakes in the two sampling periods. DVM was observed in the two lakes, performed by the most vulnerable species to fish predation (the larger Daphnia spp.), but with different patterns (direct and reverse) probably linked with the local fish community and other biotic and abiotic factors in each lake. Horizontal movements were only observed in Most Lake: D. longispina increase its abundance in open waters at night compared to the littoral points; while Ceriodaphnia spp. showed the inverse pattern. In both lakes, higher densities were often found at night in surface layers, producing a great "diurnal deficit": cladocerans remain undetected in some zones during the day (especially in the littoral areas) moving to surface layers at night.


Asunto(s)
Cladóceros , Lagos , Animales , República Checa , Conducta Predatoria , Estaciones del Año
10.
Sci Total Environ ; 750: 141303, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32871366

RESUMEN

Silver nanoparticles (Ag NPs) are present in numerous consumer products due to their antimicrobial and other unique properties, thus concerns about their potential input into aquatic ecosystems are increasing. Toxicity of Ag NPs in waterborne exposed aquatic organisms has been widely investigated, but studies assessing the potential toxic effects caused after ingestion through the food web, especially at low realistic concentrations, remain scarce. Moreover, it is not well known whether season may influence toxic effects of Ag NPs. The main objective of this study was to determine cell and tissue level responses in mussels Mytilus galloprovincialis dietarily exposed to poly-N-vinyl-2-pirrolidone/polyethyleneimine (PVP/PEI) coated 5 nm Ag NPs for 1, 7 and 21 days both in autumn and spring. Mussels were fed every day with microalgae Isochrysis galbana exposed for 24 h to a low dose (1 µg Ag/L Ag NPs) in spring and to a higher dose (10 µg Ag/L Ag NPs) in spring and autumn. Mussels fed with microalgae exposed to the high dose accumulated Ag significantly after 21 days in both seasons, higher levels being measured in autumn compared to spring. Intralysosomal metal accumulation measured in mussel digestive gland and time- and dose-dependent reduction of mussels health status was similar in both seasons. DNA strand breaks increased significantly in hemocytes at both exposure doses along the 21 days in spring and micronuclei frequency showed an increasing trend after 1 and 7 days of exposure to 1 µg Ag/L Ag NPs in spring and to 10 µg Ag/L in both seasons. Values decreased after 21 days of exposure in all the cases. In conclusion, PVP/PEI coated 5 nm Ag NPs ingested through the food web were significantly accumulated in mussel tissues and caused adverse cell and tissue level effects both in autumn and in spring.


Asunto(s)
Nanopartículas del Metal , Mytilus , Contaminantes Químicos del Agua , Animales , Ecosistema , Nanopartículas del Metal/toxicidad , Estaciones del Año , Plata/toxicidad
11.
Sci Total Environ ; 751: 141455, 2021 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-32889452

RESUMEN

The present work analyzes the impact of biochar-induced modification of soil physico-chemical properties on intra-annual growth dynamics of pioneer and fibrous grapevine roots. A scanner inserted into a buried rhizobox with a transparent side facing the plant root system was used to acquire images of pioneer and fibrous roots of control and biochar-treated plants throughout the vegetative season. Images were analyzed with ImageJ software to measure root traits. Biochar treatment increased soil pH, nutrient concentration, and water content during the driest and warmest period, while bulk density was reduced. Analysis of both pioneer and fibrous root traits highlighted a single peak of growth during the vegetative season. Pioneer roots were thicker and grew faster than fibrous roots, which were longer and more numerous. Amelioration of physico-chemical properties of biochar-amended soil stimulated an earlier root lengthening, and a higher root number at the onset of the season, which resulted in a greater canopy development compared to control plants. Later, in summer, as a consequence of the higher water content of biochar-treated soil, plants modified their root architecture, lowering the number of fibrous roots probably because of the reduced need to exploit soil for water and nutrient uptake.


Asunto(s)
Suelo , Vitis , Carbón Orgánico , Fertilidad , Raíces de Plantas , Estaciones del Año
12.
Chemosphere ; 262: 127595, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32784061

RESUMEN

Recent studies have focused on the chemistry of tropospheric halogen species which are able to deplete tropospheric ozone (O3). In this study, the effect of bromine and iodine chemistry on tropospheric O3 within the annual cycle in Asia-Pacific is investigated using the CMAQ model with the newly embedded bromine and iodine chemistry and a blended and customized emission inventory considering marine halogen emission. Results indicate that the vertical profiles of bromine and iodine species show distinct features over land/ocean and daytime/nighttime, related to natural and anthropogenic emission distributions and photochemical reactions. The halogen-mediated O3 loss has a strong seasonal cycle, and reaches a maximum of -15.9 ppbv (-44.3%) over the ocean and -13.4 ppbv (-38.9%) over continental Asia among the four seasons. Changes in solar radiation, dominant wind direction, and nearshore chlorophyll-a accumulation all contribute to these seasonal differences. Based on the distances to the nearest coastline, the onshore and offshore features of tropospheric O3 loss caused by bromine and iodine chemistry are studied. Across a coastline-centric 400-km-wide belt from onshore to offshore, averaged maximum gradient of O3 loss reaches 1.1 ppbv/100 km at surface level, while planetary boundary layer (PBL) column mean of O3 loss is more moderate, being approximately 0.7 ppbv/100 km. Relative high halogen can be found over Tibetan Plateau (TP) and the largest O3 loss (approximately 4-5 ppbv) in the PBL can be found between the western boundary of the domain and the TP. Halogens originating from marine sources can potentially affect O3 concentration transported from the stratosphere over the TP region. As part of efforts to improve our understanding of the effect of bromine and iodine chemistry on tropospheric O3, we call for more models and monitoring studies on halogen chemistry and be considered further in air pollution prevention and control policy.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Yodo/análisis , Ozono/análisis , Asia , Bromo , Halógenos/química , Yoduros , Estaciones del Año
13.
Chemosphere ; 262: 127835, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32763581

RESUMEN

This study evaluates the bioaccessibility and health risks related to heavy metals (Cd, Cr, Co, Cu, Mn, Ni, Pb, Zn and metalloid As) in airborne dust samples (TSP and PM2.5) in Zabol, Iran during the summer dust period, when peak concentration levels of PM are typically observed. High bioaccessibilities of carcinogenic metals in PM2.5 (i.e. 53.3%, 48.6% and 47.6% for Ni, Cr and As, respectively) were calculated. The carcinogenic and non-carcinogenic health risks were assessed for three exposure pathways (inhalation, ingestion and dermal contact), separately for children and adults. Non-carcinogenic inhalation risks were very high (Hazard Index: HI > 1) both for children and adults, while the carcinogenic risks were above the upper acceptable threshold of 10-4 for adults and marginally close (5.0-8.4 × 10-5) for children. High carcinogenic risks (>10-4) were found for the ingestion pathway both for children and adults, while HI values > 1 (8.2) were estimated for children. Carcinogenic and non-carcinogenic risk estimates for dermal contact were also above the limits considered acceptable, except for the carcinogenic risk for children (7.6 × 10-5). Higher non-carcinogenic and carcinogenic risks (integrated for all elements) were associated with the inhalation pathway in adults and children with the exception of carcinogenic risk for children, where the ingestion route remains the most important, while As was linked with the highest risks for nearly all exposure pathways. A comparative evaluation shows that health risks related with toxic elements in airborne particles in Sistan are among the highest reported in the world.


Asunto(s)
Contaminación del Aire/estadística & datos numéricos , Polvo/análisis , Exposición a Riesgos Ambientales/estadística & datos numéricos , Sustancias Peligrosas/análisis , Adulto , Carcinógenos/análisis , Niño , Monitoreo del Ambiente , Humanos , Irán , Metales Pesados/análisis , Medición de Riesgo , Estaciones del Año
14.
Chemosphere ; 262: 127864, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32768751

RESUMEN

Phthalate esters (PAEs) are a class of endocrine disruptors that are produced and used extensively in China. Given its presence in various products, a great quantity of PAEs flows into different aquatic systems each year. Hence, it is important to study the pollution levels and ecological risk of PAEs. This study investigated the distribution and seasonal variation of six priority PAEs in the surface water of Poyang Lake, the largest freshwater lake in China. In the wet season, the mean concentration of the total PAEs was 0.544 ± 0.173 µg/L, while the dry season concentration (1.003 ± 0.451 µg/L) nearly doubled. The most abundant PAE congeners were di-n-butyl phthalate (DBP), followed by bis (2-ethylhexyl) phthalate (DEHP). To evaluate the ecological risks in Poyang Lake, the predicted no-effect concentrations (PNECs) of four PAEs based on non-lethal effects were derived. For diethyl phthalate (DEP), butyl benzyl phthalate (BBP), DBP, and DEHP, the PNECs were 31.6, 3.30, 2.31, and 0.0210 µg/L, respectively. The tiered ecological risk assessment showed that DEP and BBP posed no risk in Poyang Lake. Meanwhile, DBP posed a potential risk in Poyang Lake, but the risk of DEHP was unacceptable and requires more actions. Specifically, the probabilities of exceeding the threshold for the protection of 95% of the aquatic organisms (HC5) were 3.30% and 4.43% for DEHP in the wet and dry season, respectively. This study provides an appropriate reference for the surface water management of PAE pollution in China.


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Ésteres/análisis , Ácidos Ftálicos/análisis , Contaminantes Químicos del Agua/análisis , Organismos Acuáticos , China , Dibutil Ftalato , Disruptores Endocrinos , Lagos , Medición de Riesgo , Ríos , Estaciones del Año , Agua
15.
Sci Total Environ ; 753: 141774, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33207436

RESUMEN

Atmospheric fine particulate matter (PM2.5) causes severe haze in China and is regarded as a threat to human health. The health effects of PM2.5 vary location by location due to the variation in size distribution, chemical composition, and sources. In this study, the cytotoxicity effect, oxidative stress, and gene expression regulation of PM2.5 in Chengdu and Chongqing, two typical urban areas in southern China, were evaluated. Urban PM2.5 in summer and winter significantly inhibited cell viability and increased reactive oxygen species (ROS) levels in A549 cells. Notably, PM2.5 in winter exhibited higher cytotoxicity and ROS level than summer. Moreover, in this study, PM2.5 commonly induced cancer-related gene expression such as cell adhesion molecule 1 (PECAM1), interleukin 24 (IL24), and cytochrome P450 (CYP1A1); meanwhile, PM2.5 commonly acted on cancer-related biological functions such as cell-substrate junction, cell-cell junction, and focal adhesion. In particular, PM2.5 in Chengdu in summer had the highest carcinogenic potential among PM2.5 at the two sites in summer and winter. Importantly, cancer-related genes were uniquely targeted by PM2.5, such as epithelial splicing regulatory protein 1 (ESRP1) and membrane-associated ring-CH-type finger 1 (1-Mar) by Chengdu summer PM2.5; collagen type IX alpha 3 chain (COL9A3) by Chengdu winter PM2.5; SH2 domain-containing 1B (SH2D1B) by Chongqing summer PM2.5; and interleukin 1 receptor-like 1 (IL1RL1) and zinc finger protein 42 (ZNF423) by Chongqing winter PM2.5. Meanwhile, important cancer-related biological functions were specially induced by PM2.5, such as cell cycle checkpoint by Chengdu summer PM2.5; macromolecule methylation by Chengdu winter PM2.5; endoplasmic reticulum-Golgi intermediate compartment membrane by Chongqing summer PM2.5; and cellular lipid catabolic process by Chongqing winter PM2.5. Conclusively, in the typical urban areas of southern China, both summer and winter PM2.5 illustrated significant gene regulation effects. This study contributes to evaluating the adverse health effects of PM2.5 in southern China and providing public health suggestions for policymakers.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , China , Monitoreo del Ambiente , Regulación de la Expresión Génica , Humanos , Material Particulado/análisis , Material Particulado/toxicidad , Estaciones del Año , Factores de Transcripción
16.
Sci Total Environ ; 753: 141629, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33207479

RESUMEN

Beekeepers attempt to manage their honey bee colonies in ways that optimize colony health. Disentangling the impact of management from other variables affecting colony health is complicated by the diversity of practices used and difficulties handling typically complex and incomplete observational datasets. We propose a method to 1) compress multi-factored management data into a single index, to holistically investigate the real world impact of management on colony mortality, and 2) simplify said index to identify the core practices for which a change in behavior is associated with the greatest improvement in survivorship. Experts scored the practices of US beekeepers (n = 18,971) documented using four years of retrospective surveys (2012-2015). Management Index scores significantly correlated with loss rates, with beekeepers most in line with recommendations suffering lower losses. The highest ranked practices varied by operation type, as recommendations accounted for the current prevalence of practices. These results validate experts' opinion using empirical data, and can help prioritize extension messages. Improving management will not prevent all losses; however, we show that few behavioral changes (in particular related to comb management, sources of new colonies and Varroa management) can lead to a non-negligible reduction in risk.


Asunto(s)
Apicultura , Varroidae , Animales , Abejas , Estudios Retrospectivos , Estaciones del Año , Encuestas y Cuestionarios
17.
Sci Total Environ ; 750: 142234, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33182167

RESUMEN

The increase in severity and occurrence of drought from environmental change poses a significant threat to freshwater ecosystems. However, many of the mechanisms by which periodic drought affects aquatic animals are poorly understood. Here we integrated physical, physiological, and behavioural measurements made in the field over a twelve-year period to provide a comprehensive understanding of the factors affecting the loss of body condition of fish in arid rivers, using the Critically Endangered freshwater sawfish (Pristis pristis) in the dryland Fitzroy River, Western Australia, as a model species. Sawfish lost condition throughout the long dry season in all years and had significantly poorer body condition throughout years characterized by low volumes of wet season flooding and little occurrence of overbank flooding. A mechanistic examination of factors leading to this loss of condition using measurements of body temperature, field energetics, and habitat use from telemetry techniques showed that the loss of condition throughout the season was likely due to substantial habitat compression and low productivity in drier years, while high rates of competition were more likely to drive this pattern in wetter years. This information can be used to forecast how climate change and water abstraction will affect aquatic fauna experiencing intermittent drought and can inform management decisions to help mitigate these threats.


Asunto(s)
Elasmobranquios , Inundaciones , Animales , Sequías , Ecosistema , Ríos , Estaciones del Año , Australia Occidental
18.
Sci Total Environ ; 750: 142183, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33182173

RESUMEN

To evaluate the transboundary pollution of organic aerosols from Northeast Asia, a highly time-resolved measurement of organic compounds was performed in March 2019 at Oki Island located in Japan, which is a remote site and less affected by local anthropogenic sources. PM2.5, water-soluble organic carbon (WSOC) concentrations, and WSOC fraction in PM2.5 showed high values on March 22-23 (high-WSOC period (HWSOC)) when the air mass passed through the area where many fire spots were detected in Northeast China. Biomass burning tracers showed higher concentration, especially levoglucosan exceeded 1 µg/m3 during the HWSOC than the low-WSOC period (LWSOC). Notably, high time-resolved measurements of biomass burning tracers and back trajectory analysis during HWSOC revealed a difference in the variation of lignin pyrolyzed compounds and anhydrous sugars on 22 and 23 March. The air mass passed to different areas in Northeast China in which fire spots were detected, such as the eastern area on the 22nd and the western area on the 23rd. Almost-organic compounds also showed high concentration and strong correlations with levoglucosan and sulfate during HWSOC. Moreover, low-carbon dicarboxylic acids (e.g., adipic acid) and secondary products from anthropogenic volatile organic compounds (e.g., 2,3-dihydroxy-4-oxopentanoic, phthalic, 5-nitrosalicylic acids), also showed a strong correlation with sulfate ions during the HWSOC and LWSOC, respectively. These higher concentrations and strong correlations with levoglucosan and sulfate during the HWSOC propose that their generation could be enhanced by biomass burning. The ratios of organics (e.g., levoglucosan/mannnosan, pinic/3-methylbutane-1,2,3-tricarboxylic acids) suggest that the high concentrations of PM2.5 and WSOC observed during the HWSOC were caused by aged organic aerosols that originated from the combustion of herbaceous plants transported from Northeast China. Our findings indicate that biomass combustion in Northeast China could significantly affect the chemical compositions and the characterization of organic aerosols in downwind regions of Northeast China.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Biomasa , Carbono/análisis , China , Monitoreo del Ambiente , Islas , Japón , Material Particulado/análisis , Estaciones del Año
19.
Sci Total Environ ; 750: 142201, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33182207

RESUMEN

Mercury (Hg) is a natural trace element found in high concentrations in top predators, including Arctic seabirds. Most current knowledge about Hg concentrations in Arctic seabirds relates to exposure during the summer breeding period when researchers can easily access seabirds at colonies. However, the few studies focused on winter have shown higher Hg concentrations during the non-breeding period than breeding period in several tissues. Hence, improving knowledge about Hg exposure during the non-breeding period is crucial to understanding the threats and risks encountered by these species year-round. We used feathers of nine migratory alcid species occurring at high latitudes to study bird Hg exposure during both the breeding and non-breeding periods. Overall, Hg concentrations during the non-breeding period were ~3 times higher than during the breeding period. In addition, spatial differences were apparent within and between the Atlantic and Pacific regions. While Hg concentrations during the non-breeding period were ~9 times and ~3 times higher than during the breeding period for the West and East Atlantic respectively, Hg concentrations in the Pacific during the non-breeding period were only ~1.7 times higher than during the breeding period. In addition, individual Hg concentrations during the non-breeding period for most of the seabird colonies were above 5 µg g-1 dry weight (dw), which is considered to be the threshold at which deleterious effects are observed, suggesting that some breeding populations might be vulnerable to non-breeding Hg exposure. Since wintering area locations, and migration routes may influence seasonal Hg concentrations, it is crucial to improve our knowledge about spatial ecotoxicology to fully understand the risks associated with Hg contamination in Arctic seabirds.


Asunto(s)
Mercurio , Animales , Regiones Árticas , Aves , Monitoreo del Ambiente , Plumas/química , Mercurio/análisis , Estaciones del Año
20.
J Environ Sci (China) ; 99: 196-209, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33183697

RESUMEN

The submicron particulate matter (PM1) and fine particulate matter (PM2.5) are very important due to their greater adverse impacts on the natural environment and human health. In this study, the daily PM1 and PM2.5 samples were collected during early summer 2018 at a sub-urban site in the urban-industrial port city of Tianjin, China. The collected samples were analyzed for the carbonaceous fractions, inorganic ions, elemental species, and specific marker sugar species. The chemical characterization of PM1 and PM2.5 was based on their concentrations, compositions, and characteristic ratios (PM1/PM2.5, AE/CE, NO3-/SO42-, OC/EC, SOC/OC, OM/TCA, K+/EC, levoglucosan/K+, V/Cu, and V/Ni). The average concentrations of PM1 and PM2.5 were 32.4 µg/m3 and 53.3 µg/m3, and PM1 constituted 63% of PM2.5 on average. The source apportionment of PM1 and PM2.5 by positive matrix factorization (PMF) model indicated the main sources of secondary aerosols (25% and 34%), biomass burning (17% and 20%), traffic emission (20% and 14%), and coal combustion (17% and 14%). The biomass burning factor involved agricultural fertilization and waste incineration. The biomass burning and primary biogenic contributions were determined by specific marker sugar species. The anthropogenic sources (combustion, secondary particle formation, etc) contributed significantly to PM1 and PM2.5, and the natural sources were more evident in PM2.5. This work significantly contributes to the chemical characterization and source apportionment of PM1 and PM2.5 in near-port cities influenced by the diverse sources.


Asunto(s)
Contaminantes Atmosféricos , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Biomasa , China , Ciudades , Monitoreo del Ambiente , Humanos , Material Particulado/análisis , Estaciones del Año , Emisiones de Vehículos/análisis
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