Papers by Magyar Donat
International Journal of Environmental Research and Public Health
Microbiological drinking water safety is traditionally monitored mainly by bacterial parameters t... more Microbiological drinking water safety is traditionally monitored mainly by bacterial parameters that indicate faecal contamination. These parameters correlate with gastro-intestinal illness, despite the fact that viral agents, resulting from faecal contamination, are usually the cause. This leaves behind microbes that can cause illness other than gastro-intestinal and several emerging pathogens, disregarding non-endemic microbial contaminants and those with recent pathogenic activity reported. This white paper focuses on one group of contaminants known to cause allergies, opportunistic infections and intoxications: Fungi. It presents a review on their occurrence, ecology and physiology. Additionally, factors contributing to their presence in water distribution systems, as well as their effect on water quality are discussed. Presence of opportunistic and pathogenic fungi in drinking water can pose a health risk to consumers due to daily contact with water, via several exposure points, such as drinking and showering. The clinical relevance and influence on human health of the most common fungal contaminants in drinking water is discussed. Our goal with this paper is to place fungal contaminants on the roadmap of evidence based and emerging threats for drinking water quality safety regulations.
Cryptogamie, Mycologie, 2017
Water-filled tree holes (dendrotelmata) are mostly ephemeral micro-ecosystems characterized by hi... more Water-filled tree holes (dendrotelmata) are mostly ephemeral micro-ecosystems characterized by high level of heterotrophic microbial activity sustained by allochthonous organic matter. In this paper, description of a five-year long observation of fungal consortia in a Norway maple tree-hole is presented. Overall, 139 fungal taxa were detected. Among them, Excipularia fusispora, Ellisembia leptospora, Rebentischia unicaudata, Tricladium castaneicola, Thielavia terricola and Alternaria spp. occurred most frequently. Our observations suggest that even an individual dendrotelma represents an exceptional microhabitat, forming a hot-spot for microfungi due to its role as a natural spore trap and its (temporarily) aquatic environment. Our results show that this aquatic micro-ecosystem supports highly diverse mycobiota with continuous temporal dynamics, with an important fraction of sporadic taxa. Cit: Magyar D., Vass M., Oros G. (2017): Dendrotelmata (water-filled tree holes) as fungal hotspots – a long term study. Cryptogamie, Mycologie, 38 (1): 55-66. doi/10.7872/crym/v38.iss1.2017.55
Agricultural and Forest Meteorology, 2016
Long-distance pollen transport can substantially raise local pollen levels, but their relative co... more Long-distance pollen transport can substantially raise local pollen levels, but their relative contribution has not yet been quantified temporally or spatially in ragweed infested regions. Using common ragweed (Ambrosia artemisiifolia) pollen accumulation at a ragweed infested area, Szeged, Hungary as a test case, this study attempted to: (1) identify, using cluster analysis, biogeographical regions that contribute to long-range transport of ragweed pollen to Szeged; (2) quantify the relative contribution of ragweed pollen from these regions; (3) Determine the relative contribution of “local” and “transported” pollen for Szeged. Using the HYSPLIT model, three-dimensional backward trajectories were produced daily over a 5-year period, 2009-2013 for ragweed pollen accumulation at Szeged. A k-means clustering algorithm using the Mahalanobis distance was applied in order to develop trajectory types. Nine back-trajectory clusters were identified. Cluster 1 (direction: from the Channel area south of Great Britain) and cluster 5 (direction: from Northern Mediterranean) were found the most relevant potential long-distance sources for Ambrosia pollen transport to Szeged. Potential Source Contribution Function (PSCF) and Concentration Weighted Trajectory (CWT) values indicated additional potential source areas including the central and eastern part of France, the northern part of Italy and the Carpathian Basin. For Szeged on non-rainy days, medium-range transport is important, while on rainy days the two transport ranges have equal weights. Based on the Granger causality, annual pollen amount transported by the atmospheric circulation is 27.8% of the annual total pollen at Szeged. From this quantity, 7.5% is added to (due to transport), while 20.3% is subtracted from (e.g. because of wash-out by frontal rainfalls going towards Szeged) local sources.
Kamarás István Hazai keresztény válaszok az ökológiai válságra 3 Béres Tamás Néhány szempont a gl... more Kamarás István Hazai keresztény válaszok az ökológiai válságra 3 Béres Tamás Néhány szempont a globális éghajlatváltozással kapcsolatos kulturális mintázatok feltárását és értelmezését célzó átfogó vizsgálat tervéhez 30 Lányi András Morális klímaváltozás 40 Formádi Katalin A klímaváltozás mint kockázat érzékelése és a megoldásával kapcsolatos attitűdök szakirodalmi vizsgálata 49 Leveleki Magdolna Az éghajlatváltozás és az adaptáció néhány lehetséges módozata 59 Trájer Attila János − Kacsala István − Padisák Judit A klímaváltozás várható hatása a szúnyogok és a lepkeszúnyogok, valamint az általuk terjesztett betegségek jövőbeli elterjedésére 73 Stenger-Kovács Csilla Az éghajlatváltozás következménye: szikes tavak és algaközösségeinek veszélyeztetettsége 86
Indoor air quality was studied in two subterranean archives ('M' and 'P') in Buda... more Indoor air quality was studied in two subterranean archives ('M' and 'P') in Budapest, Hungary after the floodings and water intrusion of the Danube river in 2010 and 2014. Airborne molds (M,P) and PM2,5 (M) were sampled. High diversity and high airborne concentration of microfungi were detected. PM2.5 concentrations indicated indoor sources. Disturbing archives (paging) increased dramatically the airborne concentrations, while dehydration of fungal spores and the predominance of non-sporulating mold colonies caused relatively lower levels in some storage rooms. In both M and P, Penicillium spp. dominated, but differences were observed in the prevalence of other fungi. Alternaria, Aspergillus, Dicyma, Myxotrichum and Stachybotrys were present in M, while Arthrinium, Chaetomium, Chrysosporium and Cladosporium were found in P. It is supposed that diversity of archived materials (different types of papers, plastics and leather) increased the fungal richness.
A 11th-century crypt was studied with aerobiological methods. Molds and bacteria were collected f... more A 11th-century crypt was studied with aerobiological methods. Molds and bacteria were collected from the air, walls and funeral materials. High moisture content of the walls had little effect on bacteria and mold growth on walls and frescos, but organic materials, eg. wooden cross, staircase, veils and plant residuals in wreath were source of mold present in high concentration in the indoor air.
Archives of Industrial Hygiene and Toxicology, 2014
Black Aspergilli (Aspergillus section Nigri) are widely distributed in various habitats. They act... more Black Aspergilli (Aspergillus section Nigri) are widely distributed in various habitats. They act as food spoilage organisms, human pathogens, and mycotoxin producers and are frequently encountered in indoor environments. Black Aspergilli, specifically A. niger, A. welwitschiae, and A. carbonarius, produce different ochratoxins and fumonisins. Ochratoxins are known to induce renal disorders following inhalation, which necessitates the determination of potential mycotoxin-producing species in our environment. This paper aimed to compare the diversity and species distribution of black Aspergilli in the indoor environments of six different countries using morphological and molecular methods. A total of 178 black Aspergillus isolates were identified from six countries. In contrast with results from previous studies, A. niger was not the only black Aspergillus detected in indoor air. Species distribution differed among countries, although the distribution in European countries (Croatia, ...
Journal of pest science, 2009
The common ragweed, Ambrosia artemisiifolia is a widespread invasive weed species in Europe. In o... more The common ragweed, Ambrosia artemisiifolia is a widespread invasive weed species in Europe. In order to estimate the deteriorative eVect of native arthropods on the invasive ragweed the eVect of three indigenous aphid species on plant development and pollen production was studied. Common ragweed plants grown in a greenhouse were artiWcially infested with Wve apterous individuals of either Aphis fabae, Brachycaudus helichrysi or Myzus persicae at the 4-leaf stage. Feeding by all three aphid species over a 5-week period signiWcantly reduced plant height, the number of male inXorescences, the length of racemes, pollen emission and plant dry mass. Brachycaudus helichrysi produced the largest colonies, followed by A. fabae and M. persicae. In a host plant choice test, B. helichrysi showed signiWcant preference for ragweed over sunXower, whereas A. fabae preferred sunXower and M. persicae did not show any preference. In a Weld experiment, the growth rate of A. fabae on caged ragweed plants was similar to that in the greenhouse, but the Wnal numbers of B. helichrysi and M. persicae after 30 days was ten and seven times lower than under greenhouse conditions, respectively. On exposed Weld plants, B. helichrysi was more abundant than other species. However, no aphid species aVected the height or dry mass of either caged or exposed plants during a 30-day period. Under controlled conditions aphids eVectively hampered development and pollen production of ragweed, however, under Hungarian Weld conditions the development of ragweed was much more dynamic, therefore no deleterious eVect of aphid feeding occurred.
Agricultural and Forest Meteorology, 2013
The paper considers the possibilities of modelling the release and dispersion of the pollen of co... more The paper considers the possibilities of modelling the release and dispersion of the pollen of common ragweed (Ambrosia artemisiifolia L.), a highly allergenic invasive weed, which is spreading through southern and central Europe. In order to provide timely warnings for the allergy sufferers, a model was developed for forecasting ragweed pollen concentrations in the air. The development was based on the system for integrated modelling of atmospheric composition (SILAM) and concentrated on spatio-temporal modelling of ragweed flowering season and pollen release, which constitutes the emission term. Evaluation of the new model against multi-annual ragweed pollen observations demonstrated that the model reproduces well the main ragweed pollen season in the areas with major plant presence, such as the Pannonian Plain, the Lyon area in France, the Milan region in Italy, Ukraine and southern Russia. The predicted start of the season is mostly within 3 days of the observed for the majority of stations in these areas. The temporal correlation between modelled and observed concentrations exceeds 0.6 for the bulk of the stations. Model application to the seasons of 2005-2011 indicated the regions with high ragweed pollen concentrations, in particular the areas where allergenic thresholds are exceeded. It is demonstrated that, due to long-range transport of pollen, high-concentration areas are substantially more extensive than the heavily infested territories.
Agricultural and Forest Meteorology, 2013
The paper considers the possibilities of modelling the release and dispersion of the pollen of co... more The paper considers the possibilities of modelling the release and dispersion of the pollen of common ragweed (Ambrosia artemisiifolia L.), a highly allergenic invasive weed, which is spreading through southern and central Europe. In order to provide timely warnings for the allergy sufferers, a model was developed for forecasting ragweed pollen concentrations in the air. The development was based on the system for integrated modelling of atmospheric composition (SILAM) and concentrated on spatio-temporal modelling of ragweed flowering season and pollen release, which constitutes the emission term. Evaluation of the new model against multi-annual ragweed pollen observations demonstrated that the model reproduces well the main ragweed pollen season in the areas with major plant presence, such as the Pannonian Plain, the Lyon area in France, the Milan region in Italy, Ukraine and southern Russia. The predicted start of the season is mostly within 3 days of the observed for the majority of stations in these areas. The temporal correlation between modelled and observed concentrations exceeds 0.6 for the bulk of the stations. Model application to the seasons of 2005-2011 indicated the regions with high ragweed pollen concentrations, in particular the areas where allergenic thresholds are exceeded. It is demonstrated that, due to long-range transport of pollen, high-concentration areas are substantially more extensive than the heavily infested territories.
Aerobiologia, 2012
The airborne dispersal of the anamorphs of the Gibberella fujikuroi species complex was studied u... more The airborne dispersal of the anamorphs of the Gibberella fujikuroi species complex was studied under pre-and postharvest maize (corn) production conditions using a 3-stage Andersen sampler. The aim of this study was to identify and analyse the size distribution of such species in air samples. Differences were observed between the concentration of large-and small-sized propagules (identified as aggregates and single microconidia, respectively), but the difference was only significant during a high concentration period (October 2007, P = 0.009). No correlation was found between the concentration of fusaria found at different sampling heights (10 and 150 cm above ground level). Fusarium isolates were collected and identified based on morphological characters and using species-specific PCR assays. The PCR analysis confirmed morphological identification of F. verticillioides, F. proliferatum and F. subglutinans. High concentrations were found during the maize harvest, loading and corn shelling. Our results showed that the monitoring of F. verticillioides should be performed at a single sampling height.
Acta Agraria Debreceniensis
The mycobiota of the Orchidarium of ELTE Botanical Garden (Budapest) has been studied applying ae... more The mycobiota of the Orchidarium of ELTE Botanical Garden (Budapest) has been studied applying aerobiological methods and isolating of tissue samples taken from 92 individuals of sixty orchid species. Among isolated basidiomycetaceous fungi 13 strains of Rhizoctonia solani were surviving in axenic culture. These symbiotic R. solani strains proved to be pathogenic on 24 cultivated plant species at varying degree. The symptoms of disease caused by R. solani strains isolated from orchids did not differ from that caused by reference strains. Three groups of strains could be separated regardless of their source or aggressivity. The host plants clustered into two groups, and their taxonomic position had no role in this respect. In general, we can assume that orchid associated Rhizoctonia strains are potential plant pathogens, and removed or withdrawn orchid stools should be treated as hazardous waste.
Long-distance pollen transport can substantially raise local pollen levels, but their relative co... more Long-distance pollen transport can substantially raise local pollen levels, but their relative contribution has not yet been quantified temporally or spatially in ragweed infested regions. Using common ragweed (Ambrosia artemisiifolia) pollen accumulation at a ragweed infested area, Szeged, Hungary as a test case, this study attempted to: (1) identify, using cluster analysis, biogeographical regions that contribute to long-range transport of ragweed pollen to Szeged; (2) quantify the relative contribution of ragweed pollen from these regions; (3) Determine the relative contribution of “local” and “transported” pollen for Szeged. Using the HYSPLIT model, three-dimensional backward trajectories were produced daily over a 5-year period, 2009-2013 for ragweed pollen accumulation at Szeged. A k-means clustering algorithm using the Mahalanobis distance was applied in order to develop trajectory types. Nine back-trajectory clusters were identified. Cluster 1 (direction: from the Channel area south of Great Britain) and cluster 5 (direction: from Northern Mediterranean) were found the most relevant potential long-distance sources for Ambrosia pollen transport to Szeged. Potential Source Contribution Function (PSCF) and Concentration Weighted Trajectory (CWT) values indicated additional potential source areas including the central and eastern part of France, the northern part of Italy and the Carpathian Basin. For Szeged on non-rainy days, medium-range transport is important, while on rainy days the two transport ranges have equal weights. Based on the Granger causality, annual pollen amount transported by the atmospheric circulation is 27.8% of the annual total pollen at Szeged. From this quantity, 7.5% is added to (due to transport), while 20.3% is subtracted from (e.g. because of wash-out by frontal rainfalls going towards Szeged) local sources.
The orchid collection of the ELTE Botanical Garden, Budapest, Hungary was monitored for airborne ... more The orchid collection of the ELTE Botanical Garden, Budapest, Hungary was monitored for airborne fungi using viable and non-viable air-sampling methods (Hirst-type and a 3-stage Andersen sampler) with three different culture media. A new culture method was also applied to identify fungal spores from Hirst-type samples. The aim of this study was to determine the diversity, human- and phytopathological potential of the air spora. To find out sources of airborne fungi, samples were collected from the air in an adjacent greenhouse and outdoors, and from necrotic plants. A total of 58 genera were found in the air samples. Cladosporium and Penicillium spp. were common members of the airborne biota. A high proportion (27.5%) of identified genera may be presented as a member of microbial consortium associated with the orchids. Airborne fungi potentially pathogenic to humans were also detected. One species, Zygosporium masonii, was new to Hungary. Statistical analysis indicated that conditions of sampling had significant effects. The principal component analysis elucidated the three principal components representing 75.34% of the total variance; the clusters of variables were related to the three types of culture media. Relative abundance of small-sized spores was high, presumably because of the fungal species composition and accelerated sedimentation of large spores in still air. Apparently, in the studied orchid greenhouse, a specific mycobiota developed due to the climate and hosts (Orchideaceae) grown there.
Tudományos ismeretterjesztés by Magyar Donat
A templom boltívei alatt szokatlan jelenet zajlik: mikrobiológusok egy kis csoportja "űrhajósruhá... more A templom boltívei alatt szokatlan jelenet zajlik: mikrobiológusok egy kis csoportja "űrhajósruhában" topogva várakozik, míg néhány munkás nagy nehezen, fémgyűrűk segítségével megemeli a templom padlójába süllyesztett többmázsás márványlapot. Most feltárul a kripta bejárata, és a régmúlt korok lehelete száll fel belőle. Hányszor lépkedtünk a katedrálisok padlójába illesztett, fényesre koptatott sírköveken, elmosódott felirataikon, míg az üvegablakok színjátékát csodáltuk! Nem sokat gondolkodtunk azon, hogy mi lehet a lábunk alatt. Aki nem fél, tartson velünk a mélybe, az eltemetett mikrobák közé.
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Papers by Magyar Donat
Tudományos ismeretterjesztés by Magyar Donat