Fluorescent biological aerosol particle measurements at  a tropical
high-altitude site in southern India during  the southwest
monsoon season

Abstract. An ultraviolet aerodynamic particle sizer (UV-APS) was continuously operated for the first time during two seasons to sample the contrasting winds during monsoon and winter to characterize the properties of fluorescent biological aerosol particles (FBAPs), at a high-altitude site in India. Averaged over the entire monsoon campaign (1 June–21 August 2014), the arithmetic mean number and mass concentrations of coarse-mode (> 1 µm) FBAPs were 0.02 cm−3 and 0.24 µg m−3, respectively, which corresponded to ∼  2 and 6 % of total aerosol loading, respectively. Average FBAP number size distribution exhibited a peak at ∼  3 µm, which is attributed to the fungal spores, as supported by scanning electron microscope (SEM) images, and these results are consistent with previous studies made for FBAPs. During 11 weeks of measurements the variability of the total coarse-mode particle number (TAP) concentration was high compared to that observed in FBAP number concentrations. The TAP and FBAP number concentrations measured at this site were strongly dependent on changes in wind direction and rainfall. During periods of westerly/southwesterly winds with heavy persistent rainfall, the TAP and FBAP concentrations exhibited very low values (1.3 and 0.005 cm−3, respectively) with no significant diurnal variations, whereas during periods of northerly winds with scattered rainfall FBAPs exhibited relatively high concentration values (0.05 cm−3) with pronounced diurnal variations, which were strongly coupled with diurnal variations in meteorological parameters. The campaign-averaged FBAP number concentrations were shown to correlate with daily patterns of meteorological parameters and were positively correlated with relative humidity (RH; R2  =  0.58) and negatively with temperature (R2  =  0.60) and wind speed (R2  =  0.60). We did not observe any significant positive correlation with precipitation as reported by previous researchers from selected areas. These measurement results confirm the fact that the ratio of PBAPs to TAP is strongly dependent on particle size and location and thus may constitute a significant proportion of total aerosol particles.

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Fluorescent Biological Aerosol Particle Measurements at a Tropical High Altitude Site in Southern India during Southwest Monsoon Season

10.5194/acp-2016-265 ◽

2016 ◽

Author(s):

A. E. Valsan ◽

R. Ravikrishna ◽

C. V. Biju ◽

C. Pöhlker ◽

V. R. Després ◽

...

Keyword(s):

High Altitude ◽

Monsoon Season ◽

Aerosol Particles ◽

Fungal Spores ◽

Southwest Monsoon ◽

Number Concentration ◽

Southern India ◽

Coarse Mode ◽

Southwest Monsoon Season ◽

Biological Aerosol Particles

Abstract. Primary Biological Aerosol Particles (PBAPs) like fungal spores, bacteria, pollen, etc. are reported to constitute large fraction of the atmospheric aerosols. They are responsible for the spread of organisms and diseases throughout the biosphere and may impact atmospheric processes and the hydrological cycle by acting as ice nuclei (IN) and giant cloud condensation nuclei (CCN). Despite their importance in the biosphere and climate, continuous measurements of PBAPs in high time and size resolutions are not available for the Indian subcontinent. Here we report the first measurements of fluorescent biological aerosol particles (FBAPs) in India. The measurements were carried out using an ultraviolet aerodynamic particle sizer (UV-APS) in Munnar, a high altitude tropical site in southern India. The study was conducted for three consecutive months during the Southwest monsoon season (1.June.2014–21.August.2014), which is marked by heavy and persistent rainfall and strong Westerly/Southwesterly clean winds. Averaged over the entire campaign arithmetic mean number and mass concentrations of coarse-mode FBAP (> 1 μm) were 0.02 cm−3 and 0.24 µg−3, respectively, which corresponded to ~ 2 and 6 % of total aerosol loading, respectively. Average FBAP number size distribution exhibited a peak at ~ 3 μm, which was most likely contributed by fungal spores, as supported by scanning electron microscope (SEM) images, and the results are consistent with previous studies made for FBAP. During eleven weeks of measurements the corresponding total (TAP) coarse mode particle number concentration was highly variable in contrast to the variability observed in FBAP number concentration. Averaged over the entire campaign the TAP number and mass concentrations were 1.8 cm−3 and 7.0 µg m−3. The TAP and FBAP number concentrations measured at this site were strongly dependent on changes in wind direction and rainfall. During the period of continuous and persistent rainfalls the TAP and FBAP concentration exhibited very low concentration levels (1.3 cm−3 and 0.005 cm−3, respectively) with no observed diurnal variations. Averaged over the entire campaign FBAP exhibited a moderately diurnal variation with highest concentration during early morning hours (~ 06:00–08:00 hrs). The campaign averaged FBAP number concentrations were shown to correlate with daily patterns of meteorological parameters and were positively correlated with relative humidity (RH; R2 = 0.58), and negatively with temperature (R2 = 0.60) and wind speed (R2 = 0.60). We did not observe any significant positive correlation with precipitation as reported by previous researchers from selected areas. These measurement results confirms the fact that fraction of PBAPs to TAP is strongly dependent on size and location and thus may constitute significant proportion of total aerosol particles.

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Similarities and differences of aerosol optical properties between southern and northern sides of the Himalayas

Atmospheric Chemistry and Physics ◽

10.5194/acp-14-3133-2014 ◽

2014 ◽

Vol 14 (6) ◽

pp. 3133-3149 ◽

Cited By ~ 25

Author(s):

C. Xu ◽

Y. M. Ma ◽

A. Panday ◽

Z. Y. Cong ◽

K. Yang ◽

...

Keyword(s):

Optical Properties ◽

Monsoon Season ◽

Diurnal Variations ◽

The Other ◽

The Tibetan Plateau ◽

Aerosol Optical Properties ◽

Coarse Mode ◽

Southern Side ◽

Northern Side ◽

The Himalaya

Abstract. The Himalaya mountains along the southern edge of the Tibetan Plateau act as a natural barrier for the transport of atmospheric aerosols from the polluted regions of South Asia to the main body of the Tibetan Plateau. In this study, we investigate the seasonal and diurnal variations of aerosol optical properties measured at two Aerosol Robotic Network (AERONET) sites on the southern side of the Himalaya (Pokhara, 812 m above sea level (a.s.l.) and EVK2-CNR, 5079 m a.s.l. in Nepal) and one on the northern side (Qomolangma (Mt. Everest) station for Atmospheric and Environmental Observation and Research, Chinese Academy of Sciences (QOMS_CAS) in Tibet, 4076 m a.s.l. in China). While observations at QOMS_CAS and EVK2-CNR can generally be representative of a remote background atmosphere, Pokhara is a lower-elevation suburban site with much higher aerosol load due to both the influence of local anthropogenic activities and to its proximity to the Indo-Gangetic Plains. The annual mean aerosol optical depth (AOD) during the investigated period was 0.05 at QOMS_CAS, 0.04 at EVK2-CNR and 0.51 at Pokhara, respectively. Seasonal variations of aerosols are profoundly affected by large-scale atmospheric circulation. Vegetation fires, peaking during April in the Himalayan region and northern India, contribute to a growing fine mode AOD at the three stations. Dust transported to these sites, wind erosion and hydrated/cloud-processed aerosols lead to an increase in coarse mode AOD during the monsoon season at QOMS_CAS and EVK2-CNR. Meanwhile, coarse mode AOD at EVK2-CNR is higher than at QOMS_CAS in August and September, indicating that the transport of coarse mode aerosols from the southern to the northern side may be effectively reduced. The effect of precipitation scavenging is clearly seen at Pokhara, which sees significantly reduced aerosol loads during the monsoon season. Unlike the seasonal variations, diurnal variations are mainly influenced by meso-scale systems and local topography. The diurnal pattern in precipitation appears to contribute to diurnal changes in AOD through the effect of precipitation scavenging. AOD exhibits diurnal patterns related to emissions in Pokhara, while it does not at the other two high-altitude sites. At EVK2-CNR, the daytime airflow carries aerosols up from lower-altitude polluted regions, leading to increasing AOD, while the other two stations are less influenced by valley winds. Surface heating influences the local convection, which further controls the vertical aerosol exchange and the diffusion rate of pollution to the surrounding areas. Fine and coarse mode particles are mixed together on the southern side of the Himalaya in spring, which may lead to the greater inter-annual difference in diurnal cycles of Ångström exponent (AE) at EVK2-CNR than that at QOMS_CAS.

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Molecular markers of biomass burning and primary biological aerosols in urban Beijing: size distribution and seasonal variation

Atmospheric Chemistry and Physics ◽

10.5194/acp-20-3623-2020 ◽

2020 ◽

Vol 20 (6) ◽

pp. 3623-3644 ◽

Cited By ~ 3

Author(s):

Shaofeng Xu ◽

Lujie Ren ◽

Yunchao Lang ◽

Shengjie Hou ◽

Hong Ren ◽

...

Keyword(s):

Molecular Markers ◽

Biomass Burning ◽

Aerosol Particles ◽

Fungal Spores ◽

Chemical Compositions ◽

Plant Debris ◽

Urban Aerosols ◽

Biological Aerosols ◽

Coarse Mode ◽

Fine Mode

Abstract. Biomass burning and primary biological aerosol particles account for an important part of urban aerosols. Floods of studies have been conducted on the chemical compositions of fine aerosols (PM2.5) in megacities where the haze pollution is one of the severe environmental issues in China. However, little is known about their size distributions in atmospheric aerosols in the urban boundary layer. Here, size-segregated aerosol samples were collected in Beijing during haze and clear days from April 2017 to January 2018. Three anhydrosugars, six primary saccharides and four sugar alcohols in these samples were identified and quantified by gas chromatography/mass spectrometry (GC/MS). Higher concentrations of a biomass burning tracer, levoglucosan, were detected in autumn and winter than in other seasons. Sucrose, glucose, fructose, mannitol and arabitol were more abundant in the bloom and glowing seasons. A particularly high level of trehalose was found in spring, which was largely associated with the Asian dust outflows. Anhydrosugars, xylose, maltose, inositol and erythritol are mainly present in the fine mode (<2.1 µm), while the others showed the coarse-mode preference. The concentrations of measured tracers of biomass burning particles and primary biological particles in the haze events were higher than those in the non-hazy days, with enrichment factors of 2–10. Geometric mean diameters (GMDs) of molecular markers of biomass burning and primary biological aerosols showed that there was no significant difference in the coarse mode (>2.1 µm) between the haze and non-haze samples, while a size shift towards large particles and large GMDs in the fine fraction (<2.1 µm) was detected during the hazy days, which highlights that the stable meteorological conditions with high relative humidity in urban Beijing may favor the condensation of organics onto coarse particles.The contributions of reconstructed primary organic carbon (POC) by tracer-based methods from plant debris, fungal spores and biomass burning to aerosol OC in the total-mode particles were in the ranges of 0.09 %–0.30 % (on average 0.21 %), 0.13 %–1.0 % (0.38 %) and 1.2 %–7.5 % (4.5 %), respectively. This study demonstrates that the contribution of biomass burning was significant in Beijing throughout the whole year with the predominance in the fine mode, while the contributions of plant debris and fungal spores dominated in spring and summer in the coarse mode, especially in sizes >5.8 µm. Our observations demonstrate that the sources, abundance and chemical composition of urban aerosol particles are strongly size dependent in Beijing, which is important to better understand the environmental and health effects of urban aerosols and should be considered in air quality and climate models.

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Similarities and differences of aerosol optical properties between southern and northern slopes of the Himalayas

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-13-20961-2013 ◽

2013 ◽

Vol 13 (8) ◽

pp. 20961-21002

Author(s):

C. Xu ◽

Y. M. Ma ◽

K. Yang ◽

Z. K. Zhu ◽

J. M. Wang ◽

...

Keyword(s):

Optical Properties ◽

Tibetan Plateau ◽

Seasonal Variations ◽

Monsoon Season ◽

Diurnal Variations ◽

The Other ◽

The Tibetan Plateau ◽

Coarse Particles ◽

Aerosol Optical Properties ◽

Coarse Mode

Abstract. The Himalayas is located at the southern edge of the Tibetan Plateau, and it acts as a natural barrier for the transport of atmospheric aerosols, e.g. from the polluted regions of South Asia to the main body of the Tibetan Plateau. In this study, we investigate the seasonal and diurnal variations of aerosol optical properties measured at the three Aerosol Robotic Network (AERONET) sites over the southern (Pokhara station and EVK2-CNR station in Nepal) and northern (Qomolangma (Mt. Everest) station for Atmospheric and Environmental Observation and Research, Chinese Academy of Sciences (QOMS_CAS) in Tibet, China) slopes of the Himalayas. While observations at QOMS_CAS and EVK2-CNR can generally be representative of a remote background atmosphere, Pokhara is an urban site with much higher aerosol load due to the influence of local anthropogenic activities. The annual mean of aerosol optical depth (AOD) during the investigated period was 0.06 at QOMS_CAS, 0.04 at EVK2-CNR and 0.51 at Pokhara, respectively. Seasonal variations of aerosols are profoundly affected by large scale atmospheric circulation. Vegetation fires, peaking during April in the Himalayan region and northern India, contribute to a growing fine mode AOD at 500 nm at the three stations. Dust transported to these sites results in an increase of coarse mode AOD during the monsoon season at the three sites. Meanwhile, coarse mode AOD at EVK2-CNR is higher than QOMS_CAS from July to September, indicating the Himalayas blocks the coarse particles carried by the southwest winds. The precipitation scavenging effect is obvious at Pokhara, which can significantly reduce the aerosol load during the monsoon season. Unlike the seasonal variations, diurnal variations are mainly influenced by meso-scale systems and local topography. In general, precipitation can lead to a decrease of the aerosol load and the average particle size at each station. AOD changes in a short time with the emission rate near the emission source at Pokhara, while does not at the other two stations in remote regions. AOD increases during daytime due to the valley winds at EVK2-CNR, while this diurnal variation of AOD is absent at the other two stations. The surface heating influences the local convection, which further controls the vertical aerosol exchange and the diffusion rate of pollutions to the surrounding areas. The Himalayas blocks most of the coarse particles across the mountains. Fine and coarse mode particles are mixed to make atmospheric composition more complex on the southern slope in spring, which leads to the greater inter-annual difference in diurnal cycles of Ångström exponent (AE) at EVK2-CNR than that at QOMS_CAS.

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Molecular characterization of organic aerosols in the Kathmandu Valley, Nepal: insights into primary and secondary sources

Atmospheric Chemistry and Physics ◽

10.5194/acp-19-2725-2019 ◽

2019 ◽

Vol 19 (5) ◽

pp. 2725-2747 ◽

Cited By ~ 17

Author(s):

Xin Wan ◽

Shichang Kang ◽

Maheswar Rupakheti ◽

Qianggong Zhang ◽

Lekhendra Tripathee ◽

...

Keyword(s):

Monsoon Season ◽

Resin Acid ◽

Fungal Spores ◽

Organic Aerosols ◽

Average Concentration ◽

Estimation Methods ◽

Anthropogenic Activity ◽

Kathmandu Valley ◽

High Concentration ◽

Annual Average

Abstract. Organic atmospheric aerosols in the Hindu Kush–Himalayas–Tibetan Plateau region are still poorly characterized. To better understand the chemical characteristics and sources of organic aerosols in the foothill region of the central Himalaya, the atmospheric aerosol samples were collected in Bode, a suburban site of the Kathmandu Valley (KV) over a 1-year period from April 2013 to April 2014. Various molecular tracers from specific sources of primary organic aerosols (POAs) and secondary organic aerosols (SOAs) were determined. Tracer-based estimation methods were employed to apportion contributions from each source. The concentrations of organic carbon (OC) and elemental carbon (EC) increased during winter with a maximum monthly average in January. Levoglucosan (a molecular tracer for biomass burning, BB) was observed as the dominant species among all the analyzed organic tracers and its annual average concentration was 788±685 ng m−3 (ranging from 58.8 to 3079 ng m−3). Isoprene-SOA (I-SOA) represented a high concentration among biogenic-SOA tracers. For the seasonality, anhydrosugars, phenolic compounds, resin acid, and aromatic SOA tracer showed similar seasonal variations with OC and EC while monosaccharides, sugar alcohols, and I-SOA tracers showed lower levels during winter. BB contributed a significant fraction to OC, averaging 24.9 %±10.4 % during the whole year, and up to 36.3 %±10.4 % in the post-monsoon season. On an annual average basis, anthropogenic toluene-derived secondary OC accounted for 8.8 % and biogenic secondary OC contributed 6.2 % to total OC. The annual contribution of fungal spores to OC was 3.2 % with a maximum during the monsoon season (5.9 %). For plant debris, it accounted for 1.4 % of OC during the monsoon. Therefore, OC is mainly associated with BB and other anthropogenic activity in the KV. Our findings are conducive to designing effective measures to mitigate the heavy air pollution and its impacts in the KV and surrounding area.

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Characterisation of biofluorescent aerosol emissions over winter and summer periods in the United Kingdom

10.5194/acp-2018-513 ◽

2018 ◽

Author(s):

Elizabeth Forde ◽

Martin Gallagher ◽

Virginia Foot ◽

Roland Sarda-Esteve ◽

Ian Crawford ◽

...

Keyword(s):

United Kingdom ◽

Relative Humidity ◽

Aerosol Particles ◽

Fungal Spores ◽

Ultra Violet ◽

Fungal Spore ◽

Complete Analysis ◽

Hierarchical Agglomerative Cluster ◽

The United Kingdom ◽

Fluorescent Particles

Abstract. Primary biological aerosol particles (PBAP) are an abundant subset of atmospheric aerosol particles which comprise viruses, bacteria, fungal spores, pollen, and fragments such as plant and animal debris. The abundance and diversity of these particles remain poorly constrained, causing significant uncertainties for modelling scenarios and for understanding the potential implications of these particles in different environments. PBAP concentrations were studied at four different sites in the United Kingdom (Weybourne, Davidstow, Capel Dewi, and Chilbolton) using an ultra-violet light induced fluorescence (UV-LIF) instrument, the Wideband Integrated Bioaerosol Spectrometer (WIBS), versions 3 and 4. Using hierarchical agglomerative cluster (HAC) analysis, particles were statistically discriminated between. Fluorescent particles and clusters were then analysed by assessing their diurnal variation and their relationship to the meteorological variables, temperature and relative humidity, and wind speed and direction. Using local land cover types, sources of the suspected fluorescent particles and clusters were then identified. Most sites exhibited a wet discharged fungal spore dominance, with the exception of one site, Davidstow, which had higher concentrations of bacteria, suggested to result from the presence of a local dairy factory. Differences were identified as to the sources of wet discharged fungal spores, with particles originating from arable and horticultural land at Chilbolton, and improved grassland areas at Weybourne. Total fluorescent particles at Capel Dewi were inferred to comprise two sources, with bacteria originating from the broadleaf and coniferous woodland and wet discharged fungal spores from nearby improved grassland areas, similar to Weybourne. The use of HAC and a higher fluorescence threshold (9SD) produced clusters which were considered to be biological following the complete analysis. More knowledge of the reaction of speciated biological particles to differences in meteorology, such as relative humidity and temperature would aid characterisation studies such as this.

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Simulating the influence of primary biological aerosol particles on clouds by heterogeneous ice nucleation

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-15437-2018 ◽

2018 ◽

Vol 18 (20) ◽

pp. 15437-15450 ◽

Cited By ~ 4

Author(s):

Matthias Hummel ◽

Corinna Hoose ◽

Bernhard Pummer ◽

Caroline Schaupp ◽

Janine Fröhlich-Nowoisky ◽

...

Keyword(s):

Pseudomonas Syringae ◽

Aerosol Particles ◽

Fungal Spores ◽

Ice Nucleation ◽

Ice Crystals ◽

Atmospheric Measurements ◽

Cloud Ice ◽

Biological Aerosol Particles ◽

Ice Phase ◽

Heterogeneous Ice Nucleation

Abstract. Primary ice formation, which is an important process for mixed-phase clouds with an impact on their lifetime, radiative balance, and hence the climate, strongly depends on the availability of ice-nucleating particles (INPs). Supercooled droplets within these clouds remain liquid until an INP immersed in or colliding with the droplet reaches its activation temperature. Only a few aerosol particles are acting as INPs and the freezing efficiency varies among them. Thus, the fraction of supercooled water in the cloud depends on the specific properties and concentrations of the INPs. Primary biological aerosol particles (PBAPs) have been identified as very efficient INPs at high subzero temperatures, but their very low atmospheric concentrations make it difficult to quantify their impact on clouds. Here we use the regional atmospheric model COSMO–ART to simulate the heterogeneous ice nucleation by PBAPs during a 1-week case study on a domain covering Europe. We focus on three highly ice-nucleation-active PBAP species, Pseudomonas syringae bacteria cells and spores from the fungi Cladosporium sp. and Mortierella alpina. PBAP emissions are parameterized in order to represent the entirety of bacteria and fungal spores in the atmosphere. Thus, only parts of the simulated PBAPs are assumed to act as INPs. The ice nucleation parameterizations are specific for the three selected species and are based on a deterministic approach. The PBAP concentrations simulated in this study are within the range of previously reported results from other modeling studies and atmospheric measurements. Two regimes of PBAP INP concentrations are identified: a temperature-limited and a PBAP-limited regime, which occur at temperatures above and below a maximal concentration at around −10 ∘C, respectively. In an ensemble of control and disturbed simulations, the change in the average ice crystal concentration by biological INPs is not statistically significant, suggesting that PBAPs have no significant influence on the average state of the cloud ice phase. However, if the cloud top temperature is below −15 ∘C, PBAP can influence the cloud ice phase and produce ice crystals in the absence of other INPs. Nevertheless, the number of produced ice crystals is very low and it has no influence on the modeled number of cloud droplets and hence the cloud structure.

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Relationships between Meteorological Parameters and Particulate Matter in Mae Hong Son Province, Thailand

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15122801 ◽

2018 ◽

Vol 15 (12) ◽

pp. 2801 ◽

Cited By ~ 14

Author(s):

Wissanupong Kliengchuay ◽

Aronrag Cooper Meeyai ◽

Suwalee Worakhunpiset ◽

Kraichat Tantrakarnapa

Keyword(s):

Air Pollution ◽

Particulate Matter ◽

Meteorological Parameters ◽

Warning System ◽

Correlation Coefficients ◽

Pm10 Concentration ◽

P Value ◽

Climate Data ◽

High Concentration ◽

Ambient Concentrations

Meteorological parameters play an important role in determining the prevalence of ambient particulate matter (PM) in the upper north of Thailand. Mae Hong Son is a province located in this region and which borders Myanmar. This study aimed to determine the relationships between meteorological parameters and ambient concentrations of particulate matter less than 10 µm in diameter (PM10) in Mae Hong Son. Parameters were measured at an air quality monitoring station, and consisted of PM10, carbon monoxide (CO), ozone (O3), and meteorological factors, including temperature, rainfall, pressure, wind speed, wind direction, and relative humidity (RH). Nine years (2009–2017) of pollution and climate data obtained from the Thai Pollution Control Department (PCD) were used for analysis. The results of this study indicate that PM10 is influenced by meteorological parameters; high concentration occurred during the dry season and northeastern monsoon seasons. Maximum concentrations were always observed in March. The PM10 concentrations were significantly related to CO and O3 concentrations and to RH, giving correlation coefficients of 0.73, 0.39, and −0.37, respectively (p-value < 0.001). Additionally, the hourly PM10 concentration fluctuated within each day. In general, it was found that the reporting of daily concentrations might be best suited to public announcements and presentations. Hourly concentrations are recommended for public declarations that might be useful for warning citizens and organizations about air pollution. Our findings could be used to improve the understanding of PM10 concentration patterns in Mae Hong Son and provide information to better air pollution measures and establish a warning system for the province.

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EVALUATION OF INTENSITY OF HUMORAL IMMUNITY TO MEASLES AND RUBELLA IN PREGNANT WOMEN IN MOSCOW

Journal of microbiology epidemiology immunobiology ◽

10.36233/0372-9311-2017-3-91-98 ◽

2017 ◽

pp. 91-98 ◽

Cited By ~ 3

Author(s):

A. V. Nozdracheva ◽

T. A. Semenenko ◽

S. G. Mardanly ◽

S. V. Rotanov

Keyword(s):

Pregnant Women ◽

Humoral Immunity ◽

Adult Population ◽

Significant Proportion ◽

Older Individuals ◽

High Concentration ◽

Causative Agents ◽

Maximum Proportion ◽

Measles Vaccination ◽

Specific Igg

Aim. Qualitative and quantitative evaluation of humoral immunity regarding causative agents of controllable infections in pregnant women in Moscow. Materials and methods. Sera of 559 pregnant and 201 non-pregnant women were studied for the presence of antibodies against measles and rubella virus by ELISA. Results. A significant proportion of individuals seronegative to measles was detected among pregnant (21.5%) and non-pregnant (29.1%) women aged 18 - 45, that exceeds the level acceptable by regulatory requirements by 3.1 and 4.2 times, respectively. The parameter increased with age and among seropositive individuals a high concentration of IgG against measles was noted. This gives evidence, that older individuals are not covered by measles vaccination enough, and a significant part of them has post-infection immunity that is higher and more robust compared with post-vaccination. Regarding rubella infection, a more favorable situation was established: proportion of seronegative individuals among the examined was 8.9 and 10.5%, respectively. The proportion of seronegative individuals decreased with age, and by age 36 - 45 reached the minimal 4,7%. A maximum amount of rubella seronegative individuals was detected in the 26-30 age group - 12.5%, as well as maximum proportion of individuals who have high concentration of specific IgG. An increase of the amount of seronegative results was observed with the increase of gestation period for both infections. Correlation between intensity of immunity against measles and rubella in the examined women was not present. Conclusion. Means for development of extra vaccination of the adult population and execution of laboratory examination of pregnant and women planning pregnancy are proposed regarding not only rubella, but also measles.

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Regional-scale simulations of fungal spore aerosols using an emission parameterization adapted to local measurements of fluorescent biological aerosol particles

Atmospheric Chemistry and Physics ◽

10.5194/acp-15-6127-2015 ◽

2015 ◽

Vol 15 (11) ◽

pp. 6127-6146 ◽

Cited By ~ 26

Author(s):

M. Hummel ◽

C. Hoose ◽

M. Gallagher ◽

D. A. Healy ◽

J. A. Huffman ◽

...

Keyword(s):

Aerosol Particles ◽

Regional Scale ◽

Fungal Spores ◽

Fungal Spore ◽

Specific Humidity ◽

Small Scale ◽

Area Index ◽

Reactive Trace Gases ◽

Mean Square Errors ◽

Biological Aerosol Particles

Abstract. Fungal spores as a prominent type of primary biological aerosol particles (PBAP) have been incorporated into the COSMO-ART (Consortium for Small-scale Modelling-Aerosols and Reactive Trace gases) regional atmospheric model. Two literature-based emission rates for fungal spores derived from fungal spore colony counts and chemical tracer measurements were used as a parameterization baseline for this study. A third, new emission parameterization for fluorescent biological aerosol particles (FBAP) was adapted to field measurements from four locations across Europe. FBAP concentrations can be regarded as a lower estimate of total PBAP concentrations. Size distributions of FBAP often show a distinct mode at approx. 3 μm, corresponding to a diameter range characteristic for many fungal spores. Previous studies for several locations have suggested that FBAP are in many cases dominated by fungal spores. Thus, we suggest that simulated FBAP and fungal spore concentrations obtained from the three different emission parameterizations can be compared to FBAP measurements. The comparison reveals that simulated fungal spore concentrations based on literature emission parameterizations are lower than measured FBAP concentrations. In agreement with the measurements, the model results show a diurnal cycle in simulated fungal spore concentrations, which may develop partially as a consequence of a varying boundary layer height between day and night. Temperature and specific humidity, together with leaf area index (LAI), were chosen to drive the new emission parameterization which is fitted to the FBAP observations. The new parameterization results in similar root mean square errors (RMSEs) and correlation coefficients compared to the FBAP observations as the previously existing fungal spore emission parameterizations, with some improvements in the bias. Using the new emission parameterization on a model domain covering western Europe, FBAP in the lowest model layer comprise a fraction of 15% of the total aerosol mass over land and reach average number concentrations of 26 L−1. The results confirm that fungal spores and biological particles may account for a major fraction of supermicron aerosol particle number and mass concentration over vegetated continental regions and should thus be explicitly considered in air quality and climate studies.

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