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1.
Chemosphere ; 351: 141257, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38244871

RESUMEN

Airborne polycyclic aromatic hydrocarbons (PAHs) and their derivatives are of particular concern for population health due to their abundance and toxicity via inhalation. Lung toxicity testing includes exposing lung epithelial cell lines to PAHs in a culture medium containing inorganic species, lipids, proteins, and other biochemicals where the cell response is influenced among others by the toxic chemical accessibility in the medium. While inhalation bioaccessibility of PAHs and other toxicants was previously studied in surrogate lung fluids, studies measuring bioaccessibility in cell culture media are rare. In this work, a method was developed to characterize PAH bioaccessibility in a culture medium used for mouse lung epithelial (FE1) cells. Further, the optimised method was tested using commercially available standard reference material of urban particulate matter (PM) as well as polyurethane foam passive air samplers (PUF-PAS). The method provided a high precision and recovery of analytes, indicating no losses during sample processing and analysis. PAHs had non-linear concentration-responses, with the culture medium approaching saturation with PM concentration of 500 µg mL-1. The results showed that phenanthrene, a 3-ring PAH, was significantly more bioaccessible than ≥4-ring congeners in the culture medium (up to ∼2.5 folds; p < 0.05). Finally, using pre-deployed PUF-PAS from a residential and an industrial site, five PAHs were found in the culture medium, including naphthalene, phenanthrene, anthracene, fluoranthene, and pyrene. This work provides a proof of concept to enable future studies to assess the inhalation bioaccessibility of polycyclic aromatic compounds and other airborne pollutants collected using PUF-PAS.


Asunto(s)
Contaminantes Atmosféricos , Fenantrenos , Hidrocarburos Policíclicos Aromáticos , Compuestos Policíclicos , Animales , Ratones , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Material Particulado/toxicidad , Material Particulado/análisis , Fenantrenos/análisis , Compuestos Policíclicos/análisis , Técnicas de Cultivo de Célula , Monitoreo del Ambiente/métodos
2.
Sci Total Environ ; 913: 169678, 2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-38159775

RESUMEN

The number of studies dealing with airborne microplastics (MPs) is increasing but sampling and sample treatment are not standardized, yet. Here, a fast and reliable method to characterize MPs is presented. It involves the study of two passive sampling devices to collect atmospheric bulk deposition (wet and dry deposition) and three digestion methods (two alkaline-oxidative and an oxidative) to treat the samples. The alkaline-oxidative method based on KOH and NaClO was selected for a mild organic matrix digestion. In addition, some operational parameters of a high-throughput quantum cascade laser-based infrared device (LDIR) were optimized: an effective automatic tiered approach to differentiate fibres from particles (>90 % success in validation) and a criterion to establish positive matches when comparing an unknown spectrum against the spectral database (proposed match index > 0.85). The procedural analytical recoveries were very good for particles (82-90 %) and slightly lower for fibres (62-73 %). Finally, the amount and type of MPs deposited at a sub-urban area NW Spain were evaluated. Most common polymers were Polyethylene (PE), Polypropylene (PP) and Polyethylene terephthalate (PET). The deposition rates ranged 98-1220 MP/m2/day, ca. 1.7 % of the total collected particles. More than 50 % of the total MPs deposited were in the 20-50 µm size range, whereas fibres were mostly in the 50-500 µm size range.

3.
Sci Total Environ ; 880: 163224, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37019236

RESUMEN

In this study, ambient air, surface water and sediment samples were simultaneously collected and analyzed for PCBs to investigate their levels, spatial variations and exchanges between these three compartments at different sampling sites for 12 months in Bursa, Türkiye. During the sampling period, a total of 41 PCB concentrations were determined in the ambient air, surface water (dissolved and particle phase) and sediment. Thus, 945.9 ± 491.6 pg/m3 (average ± STD), 53.8 ± 54.7 ng/L, 92.8 ± 59.3 ng/L and 71.4 ± 38.7 ng/g, respectively. The highest concentrations of PCBs in the ambient air and in water particulate phase were measured at the industrial/agricultural sampling site (1308.6 ± 252.1 pg/m3 and 168.7 ± 21.2 ng/L, respectively), ∼ 4-10 times higher than background sites; while the highest concentrations in the sediment and dissolved phase were measured at the urban/agricultural sampling sites (163.8 ± 27.0 ng/L and 145.7 ± 15.3 ng/g, respectively), ∼ 5-20 times higher than background sites. PCB transitions between ambient air-surface water (fA/fW) and surface water-sediment (fW/fS) were investigated by fugacity ratio calculations. According to the fugacity ratios obtained, volatilization from the surface water to the ambient air was observed at all sampling sites (98.7 % of fA/fW ratios are <1.0). Additionally, it has been determined that there is a transport from the surface water to the sediment (100.0 % of fW/fS ratios are higher than 1.0). The flux values in ambient air-surface water and surface water-sediment environments ranged from -1.2 to 1770.6 pg/m2-day and from -225.9 to 0.001 pg/m2-day, respectively. The highest flux values were measured for PCBs with low chlorine content (Mono-, Di-Cl PCBs), while the lowest flux values were measured for the high chlorine content PCBs (Octa-, Nona- and Deca-Cl PCBs). As it was determined in this study that surface waters contaminated by PCBs have the potential to pollute both air and sediments, it will be important to take measures to protect surface waters.

4.
Sci Total Environ ; 858(Pt 1): 159875, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36461561

RESUMEN

Short and medium chain chlorinated paraffins (SCCPs and MCCPs) attract increasing attentions due to their persistence, long-range transport capacity. Their gas/particle partitioning from the production emission source, the effects to the ambient environment and exposure for employees are worth revealing. Polyurethane foam based passive air samplers (PUF-PAS) was deployed to determine the environmental levels of SCCPs (63.4-719.7 ng/m3) and MCCPs (151.6-1009.2 ng/m3) in the gas-phase and particle-phase both in the outdoor air in a CP production plant and the indoor air in the workshops. Extremely high SCCPs were found in the chlorination workshop and outdoor samples nearby, attributing to the release during the production. In the workshops, dramatically higher SCCP concentrations were determined than outdoors. SCCPs and MCCPs predominated in the gas-phase with a proportion >80 %. C10-CPs and C14-CPs were dominated with a proportion higher than 20 % and 50 %, respectively. Significant correlations between log Kp' and log PL0 and log KOA were observed in the outdoor air in a CP production plant and the indoor air in the workshops, respectively. A multivariate mechanism based on adsorption by organic matters and influenced by absorption processes might determine the gas/particle partitioning of CPs in the production source area. Two scenarios of occupational exposure i.e. working in the workshops and working outdoors were considered. Higher occupational exposure via inhalation to MCCPs was found for employees than SCCPs in the workshops, which was estimated to be 137.1 ng/kg/day at a worst case. No obvious adverse effects were observed for occupational employees in this CP production plant.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Exposición Profesional , Humanos , Parafina , Adsorción , Halogenación
5.
Sci Total Environ ; 843: 157094, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35779735

RESUMEN

Chlorinated paraffins (CPs) are synthetic chemicals that are produced at high volumes and have a global presence. CPs are generally divided into three groups based on their carbon chain lengths: short-chain CPs (SCCPs, C10-13), medium-chain CPs (MCCPs, C14-17), and long-chain CPs (LCCPs, C≥18). SCCPs have been formally recognized as persistent organic pollutants (POPs) and have been listed under the Stockholm Convention on POPs. Concerns about increases in MCCP and LCCP production as replacements for SCCP products are rising, given their similar properties to SCCPs and the fact that they remain relatively understudied with only a few reported measurements in air. Passive air samplers with polyurethane foam disks (PUF-PAS), which have been successfully applied to SCCPs, provide an opportunity to expand the existing body of data on MCCP and LCCP air concentrations, as they are inexpensive and require little maintenance. The uptake of MCCPs and LCCPs by PUF disk samplers is characterized in this paper based on newly derived PUF-air partitioning coefficients using COSMOtherm. The ability of PUF disk samplers to capture both gas-phase and particle fractions is important because MCCPs and LCCPs have reduced volatility compared to SCCPs and therefore are mainly associated with particulate matter in air. In addition, due to their use as additives in plastics and rubber products, they are associated with micro- and nanoplastics, which are considered to be potential vectors for the long-range atmospheric transport (LRAT) of these chemicals. The review has highlighted other limitations to reporting of MCCPs and LCCPs in air, including the lack of suitable analytical standards and the requirement for advanced analytical methods to detect and resolve these complex mixtures. Overall, this review indicates that further research is needed in many areas for medium- and long-chain chlorinated paraffins in order to better understand their occurrence, transport and fate in air.


Asunto(s)
Contaminantes Ambientales , Hidrocarburos Clorados , China , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Hidrocarburos Clorados/análisis , Parafina/análisis , Material Particulado
6.
Environ Sci Pollut Res Int ; 29(21): 32082-32092, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35013944

RESUMEN

In this study, the concentration of ambient persistent organic pollutants (POPs) such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were measured for 12 months in urban and semi-urban areas using a passive air sampler. During the sampling period, a total of 14 PAH (∑14PAH) concentrations measured in urban and semi-urban areas were found to be 54.4 ± 22.6 ng/m3 and 51.7 ± 34.3 ng/m3, respectively. Molecular diagnostic ratios (MDRs) were used to determine PAH sources. According to the MDR values, combustion sources were the most important PAH sources in both sampling areas. However, since the urban area is close to the industrial zone, the combustion sources occurred at high temperatures (> 800 °C), while the sources in the semi-urban area generally consisted of petrogenic fuel combustion. ∑50PCB concentrations measured in the urban and semi-urban areas were found to be 522.5 ± 196.9 pg/m3 and 439.5 ± 166.6 pg/m3, respectively. Homologous group distributions were used to determine the source of PCBs. According to the homologous group distributions, tri-, tetra-, and penta-chlorinated PCBs were dominant in both sampling areas. ∑10OCP concentrations measured in urban and semi-urban areas were found as 242.5 ± 104.6 pg/m3 and 275.9 ± 130.9 pg/m3, respectively. Also, α-HCH/γ-HCH and ß-/(α + γ)-HCH ratios were used to determine the source of OCPs. Lindane was the predominant OCP in both sampling areas.


Asunto(s)
Contaminantes Atmosféricos , Hidrocarburos Clorados , Plaguicidas , Bifenilos Policlorados , Hidrocarburos Policíclicos Aromáticos , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Hidrocarburos Clorados/análisis , Contaminantes Orgánicos Persistentes , Plaguicidas/análisis , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Turquía
7.
Chemosphere ; 266: 129015, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33261838

RESUMEN

XAD-based passive air samplers (PAS) were used to evaluate organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and some current use pesticides (chlorotalonil, trifluralin and dichlofluanid) in the atmosphere of Argentinian Patagonia. The PAS were deployed for 12 months during three consecutive years along a longitudinal (Rio Negro watershed) and a latitudinal (Patagonian coast) transect. Endosulfan, trifluralin and DDT-related substances were the most prevalent pesticides in the Rio Negro watershed, an intensive agricultural basin, consistent with ongoing use of endosulfan at the time of sampling. Concentrations of industrial contaminants were low (mean 25 pg/m3 and 1.9 pg/m3 for Σ38 PCBs, and Σ5PBDEs, respectively) and similar among sites. However, along the Patagonian coast, air concentrations of total contaminants were highly variable (14-400 pg/m3) with highest values recorded at Bahia Blanca, an important industrial area that is also downwind of the most intensively agriculturally used area of Argentina. Contaminant levels decreased toward the south, with the exception of the southernmost sampling site (Rio Gallegos) where a slight increase of total pollutant levels was observed, mainly due to the lower chlorinated PCB congeners. Interannual variability was small, although the last year tended to have slightly higher levels for different contaminant groups at most sampling sites. This large-scale spatial atmospheric monitoring of POPs and some CUPs in the South of Argentina highlights the important and continuing role of rural and urban areas as emission sources of these chemicals.


Asunto(s)
Contaminantes Atmosféricos , Hidrocarburos Clorados , Plaguicidas , Bifenilos Policlorados , Contaminantes Atmosféricos/análisis , Argentina , Atmósfera , Monitoreo del Ambiente , Hidrocarburos Clorados/análisis , Contaminantes Orgánicos Persistentes , Plaguicidas/análisis , Bifenilos Policlorados/análisis
8.
Artículo en Inglés | MEDLINE | ID: mdl-32244315

RESUMEN

In the present study, mercury (Hg) concentrations were investigated in lichens (Flavoparmelia caperata (L.) Hale, Parmelia saxatilis (L.) Ach., and Xanthoria parietina (L.) Th.Fr.) collected in the surrounding of the dismissed Abbadia San Salvatore Hg mine (Monte Amiata district, Italy). Results were integrated with Hg concentrations in tree barks and literature data of gaseous Hg levels determined by passive air samplers (PASs) in the same area. The ultimate goal was to compare results obtained by the three monitoring techniques to evaluate potential mismatches. Lichens displayed 180-3600 ng/g Hg, and Hg concentrations decreased exponentially with distance from the mine. Mercury concentration was lower than in Pinus nigra barks at the same site. There was a moderate correlation between Hg in lichen and Hg in bark, suggesting similar mechanisms of Hg uptake and residence times. However, correlation with published gaseous Hg concentrations (PASs) was moderate at best (Kendall Tau = 0.4-0.5, p > 0.05). The differences occurred because a) PASs collected gaseous Hg, whereas lichens and barks also picked up particulate Hg, and b) lichens and bark had a dynamic exchange with the atmosphere. Lichen, bark, and PAS outline different and complementary aspects of airborne Hg content and efficient monitoring programs in contaminated areas would benefit from the integration of data from different techniques.


Asunto(s)
Contaminantes Atmosféricos , Líquenes , Mercurio , Contaminantes Atmosféricos/análisis , Atmósfera , Monitoreo del Ambiente , Italia , Mercurio/análisis
9.
Sci Total Environ ; 662: 646-654, 2019 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-30703722

RESUMEN

Polyurethane foam (PUF) disks in passive air samplers (PAS) and passive dry deposition (Pas-DD) collectors were used to assess the presence of persistent organic pollutants (POPs) and current-use pesticides (CUPs) in a rural area of central Chile (Peumo, VI Region). The samplers were exposed from September 2015 (spring) to March 2016 (summer), with the PUFs collected at intervals of 30, 60, and 90 days. Both samplers (PUF-PAS and Pas-DD) captured more than one pesticide per sampling period. Chlorpyrifos-ethyl and pyrimethanil presented the highest air concentration with PUF-PAS (3470.2 ng m-3 for chlorpyrifos-ethyl and 52.8 ng m-3 for pyrimethanil). The deposited amount of chlorpyrifos-ethyl, pyrimethanil, penconazole, diazinon and malathion in some Pas-DD, was superior to amount of pesticides captured by PUF-PAS. Differences between the amount deposited and captured by each sampler should be studied in greater detail, because wind speed, atmospheric particulate matter size and sampler design are some fundamental variables in this process. These results provide preliminary information on the presence of current-use pesticides in the atmosphere of Peumo, VI Region, serving as a foundation for future environmental monitoring programs.

10.
Chemosphere ; 199: 89-97, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29433032

RESUMEN

The transfer of dioxin from the environment to the food is a problem in a consumers' health protection. The study aimed to determine the concentration of dioxins in free-range chicken eggs, air and soil samples, collected during 12 months on an individual small farm, located in Malopolska region, Poland. In the majority of analyzed eggs, the concentrations of dioxin exceeded several times the legal limit of 2.5 pg WHO-TEQ g-1fat. Seasonal changes in the PCDD/Fs congeners in egg, air and soil samples were studied. During the winter season, when the combustion processes of the solid fuel in domestic furnaces are intensive, the PM10 concentration in the Malopolska region exceeds the legal limit (50µg/m3) even eight times. In this period, eggs, air and soil samples showed a higher share of PCDFs with a specific contribution of 2,3,7,8-TCDF. During the summer months, in the egg, air and soil samples, the share of PCDDs is higher with dominant OCDD and 1,2,3,4,6,7,8-HpCDDs, showing the effect of other combustion processes such as grass utilization or burning plastic wastes in controlled fires. In August, the month of the highest average air temperature and lowest rainfall amount, the highest toxicity of PCDD/Fs in eggs (9.52pgWHO-TEQ g-1fat) was found. Due to the similarity of the shares of PCDD/Fs congeners in total WHO-TEQ value we can take into account the influence of toxicity of PCDD/Fs in the air and soil on the toxicity in the eggs.


Asunto(s)
Contaminantes Atmosféricos/análisis , Dioxinas/análisis , Huevos/análisis , Granjas , Dibenzodioxinas Policloradas/análisis , Estaciones del Año , Contaminantes del Suelo/análisis , Animales , Pollos , Dibenzofuranos Policlorados/análisis , Polonia
11.
Chemosphere ; 178: 458-465, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28342994

RESUMEN

Passive air samplers were used to evaluate long-term trends and spatial distribution of trace organic compounds in Antarctica. Duplicate PUF disk samplers were deployed at six automatic weather stations in the coastal area of the Ross sea (East Antarctica), between December 2010 and January 2011, during the XXVI Italian Scientific Research Expedition. Among the investigated persistent organic compounds, Hexachlorobenzene was the most abundant, with air concentrations ranging from 0.8 to 50 pg m-3. In general, the following decreasing concentration order was found for the air samples analyzed: HCB > PeCB > PCBs > DDTs > HCHs. While HCB concentrations were in the same range as those reported in the atmosphere of other Antarctic sampling areas and did not show a decline, HCHs and DDTs levels were lower or similar to those determined one or two decades ago. In general, the very low concentrations reflected the pristine state of the East Antarctica air. Backward trajectories indicated the prevalence of air masses coming from the Antarctic continent. Local contamination and volatilization from ice were suggested as potential sources for the presence of persistent organic pollutants in the atmosphere.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Compuestos Orgánicos/análisis , Regiones Antárticas , Atmósfera/análisis , Monitoreo del Ambiente/instrumentación , Hexaclorobenceno/análisis , Italia , Bifenilos Policlorados/análisis
12.
Chemosphere ; 168: 1345-1355, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27916263

RESUMEN

Polyurethane foam (PUF) passive samplers were employed to assess air concentrations of polychlorinated biphenyls (PCBs) in background, agricultural, semi-urban, urban and industrial sites in Bursa, Turkey. Samplers were deployed for approximately 2-month periods from February to December 2014 in five sampling campaign. Results showed a clear rural-agricultural-semi-urban-urban-industrial PCBs concentration gradient. Considering all sampling periods, ambient air concentrations of Σ43PCBs ranged from 9.6 to 1240 pg/m3 at all sites with an average of 24.1 ± 8.2, 43.8 ± 24.4, 140 ± 190, 42.8 ± 24.6, 160 ± 280, 84.1 ± 105, 170 ± 150 and 280 ± 540 pg/m3 for Mount Uludag, Uludag University Campus, Camlica, Bursa Technical University Osmangazi Campus, Hamitler, Agakoy, Kestel Organised Industrial District and Demirtas Organised Industrial District sampling sites, respectively. The ambient air PCB concentrations increased along a gradient from background to industrial areas by a factor of 1.7-11.4. 4-Cl PCBs (31.50-81.60%) was the most dominant homologue group at all sampling sites followed by 3-Cl, 7-Cl, 6-Cl and 5-Cl homologue groups. Sampling locations and potential sources grouped in principal component analysis. Results of PCA plots highlighted a large variability of the PCB mixture in air, hence possible related sources, in Bursa area. Calculated inhalation risk levels in this study indicated no serious adverse health effects. This study is one of few efforts to characterize PCB composition in ambient air seasonally and spatially for urban and industrial areas of Turkey by using passive samplers as an alternative sampling method for concurrent monitoring at multiple sites.


Asunto(s)
Contaminantes Atmosféricos/análisis , Exposición por Inhalación/análisis , Bifenilos Policlorados/análisis , Contaminantes Atmosféricos/química , Monitoreo del Ambiente/instrumentación , Monitoreo del Ambiente/métodos , Humanos , Neoplasias , Bifenilos Policlorados/química , Poliuretanos/química , Análisis de Componente Principal , Medición de Riesgo , Estaciones del Año , Turquía
13.
Sci Total Environ ; 573: 1406-1412, 2016 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-27457675

RESUMEN

Passive air samplers were deployed in 18 rural and urban locations in the densely populated Buenos Aires district to investigate airborne polychlorinated dibenzo-p-dioxin and polychlorinated-dibenzofuran (PCDD/Fs) profiles, sources and spatial patterns. Atmospheric concentrations reported as total toxic equivalents (TEQs), 2378-substituted (∑17PCDD/F) and 4-8 homologous groups (∑4-8PCDD/F) were highly variable and significantly correlated to urban scale. The rural average (3.0±2.7fgTEQm-3) was thirty times less than metropolitan values (90±51fgTEQm-3), with urban cluster (5.4±4.0fgTEQm-3) and urbanized area (33±50fgTEQm-3) in an intermediate position. A rural outlier exhibited the highest TEQ values (295-296fgTEQm-3) suggesting a local source. Principal component analyses (PCA) performed for ∑17PCDD/F and ∑4-8PCDD/F to identify source contributions showed more significant results for homologue groups compared to 17 congeners (83 and 45% of total variability explained, respectively) pointing to dominant diesel emissions enriched in TeCDF in rural areas, and open burning and industrial sources characterized by TeCDD, PeCDD contributing most in urbanized and metropolitan areas. Homologue group PCA also performed better clustering samples according to sources and TEQ concentrations. The PCDD/Fs profile of the rural outlier dominated by HxCDF and HpCDD/F showed a typical municipal incineration signature confirming the presence of local source.


Asunto(s)
Contaminantes Atmosféricos/análisis , Dibenzofuranos Policlorados/análisis , Dibenzodioxinas Policloradas/análisis , Argentina , Ambiente , Monitoreo del Ambiente
14.
Chemosphere ; 144: 1459-66, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26495831

RESUMEN

In order to evaluate the impact of intensive agriculture on air quality in the most productive and populated Argentina's Pampas, a comprehensive assessment of airborne Endosulfan (∑Endo) was performed using polyurethane passive samplers deployed from 2010 to 2013 covering the critical period of Endosulfan restrictions at twenty nine sites in the Rural Pampa and Great Buenos Aires Metropolitan Area (GBA: Horticultural and Urban subareas). ∑Endo concentrations were very high and variable (0.01-63 ng m(-3)), exceeding worldwide reported maxima at Horticultural GBA and Rural Pampa with lowest values at Urban GBA (geometric means: 3.1, 1.1 and 0.53 ng m(-3), respectively). The composition was relatively fresh with strong predominance of Endo I (72 ± 18%) over Endo II (23 ± 15%) and Endo SO4 (5 ± 10%). Airborne ∑Endo was significantly correlated to annual soybean crop in Rural Pampa. ∑Endo concentrations showed a temporal pattern defined by consistent peaks enriched in Endo I during summer application periods, cold temperature minima with higher proportions of Endo SO4 and a general exponentially declining trend over time related to incipient control policies.


Asunto(s)
Contaminantes Atmosféricos/análisis , Endosulfano/análisis , Agricultura , Argentina , Monitoreo del Ambiente , Estaciones del Año
15.
Environ Pollut ; 200: 35-41, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25686886

RESUMEN

The rice canopy in paddy fields can influence the air-soil exchange of organic chemicals. We used paired passive air samplers to assess the exchange of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in a paddy field, South China. Levels of OCPs and light PAHs were generally higher under the canopy than above it. We found that the rice canopy can physically obstruct the evaporation of most OCPs and light PAHs, and can also act as a barrier to the gaseous deposition of p,p'-DDT and heavy PAHs. Paddy fields can behave as a secondary source of OCPs and light PAHs. The homolog patterns of these two types of chemical varied slightly between the air below and above the rice canopy, implying contributions of different sources. Paired passive air samplers can be used effectively to assess the in situ air-soil exchange of PAHs and OCPs in subtropical paddy fields.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/instrumentación , Hidrocarburos Clorados/análisis , Oryza , Plaguicidas/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Agricultura , China , Monitoreo del Ambiente/métodos , Suelo/química , Contaminantes del Suelo/análisis
16.
Sci Total Environ ; 491-492: 17-27, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-24852516

RESUMEN

Twenty-nine toxic congeners including 17 polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) and 12 dioxin-like polychlorinated biphenyls (dl-PCBs) were determined using passive air samplers (PAS) at ten satellite cities of Seoul for two years. Chemical analysis was done by high resolution gas chromatography (HRGC) coupled with high resolution mass spectrometry (HRMS). The ten monitoring sites represent urban-residential, industrial, urban-rural mixed, and rural types of regions in Gyeonggi Province, Republic of Korea. The concentrations of PCDDs/PCDFs and dioxin-like PCBs ranged from 0.59 pg·day(-1) to 29.7 pg·day(-1) and from 3.44 pg·day(-1) to 99.7 pg·day(-1), respectively with the highest values at industrial areas. The relative abundance of more toxic congeners (tetra- and penta-chlorinated PCDDs/PCDFs) was the highest in urban-rural mixed group despite the less emission sources than industrial group. It implies that this group was under the influence of fugitive emissions that have not yet been identified or regulated. This study reports the first attempt of atmospheric PCDDs/PCDFs and dl-PCB measurements with PAS in the monitoring network of Korea, which highlights the efficacy of PAS in continuous and long-term monitoring of those species particularly at regions that could easily slip out of environmental governance or of low accessibility to monitoring.


Asunto(s)
Contaminantes Atmosféricos/análisis , Benzofuranos/análisis , Monitoreo del Ambiente/métodos , Bifenilos Policlorados/análisis , Dibenzodioxinas Policloradas/análogos & derivados , Polímeros/análisis , Ciudades , Monitoreo del Ambiente/instrumentación , Dibenzodioxinas Policloradas/análisis , Poliuretanos/química , Seúl
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