Biomedical subjects

J Dutkiewicz

Publications and source records attributed to J Dutkiewicz.

At least 19 recordsLinked to original sources

PubMed2006

TEM and HREM study of Al3Zr precipitates in an Al-Mg-Si-Zr alloy.

The structure of Al(3)Zr precipitates in Al-1.0Mg-0.6Si-0.5Zr (in wt.%) alloy was investigated using conventional transmission electron microscopy (TEM) and high-resolution TEM (HREM). After annealing of the alloy in the temperature range 450-540 degrees C, spherical precipitates of metastable L1(2)-Al(3)Zr phase appeared nearly homogeneously within the matrix, and elongated particles were found at grain boundaries. L1(2)-structured Al(3)Zr were about 20-30 nm in diameter and coherent with the matrix. Inside some of them, planar faults parallel to {100} planes were revealed by use of HREM. Most probably, these faults are an indication of the transition stage of transformation to the stable D0(23)-type Al(3)Zr phase. The elongated precipitates (about 100 nm) were identified as D0(22)-type Al(3)Zr. Energy-dispersive X-ray analysis showed that they contain, apart from Al, mainly Zr with small amounts of Si. The substitution of Al by Si increased the stability of the D0(22)-Al(3)Zr as compared with D0(23)-Al(3)Zr.

Journal Article↗

PubMed2006

Structure studies of ball-milled ZrCuAl, NiTiZrCu and melt-spun ZrNiTiCuAl alloys.

ZrNiTiCu and ZrNiTiCuAl alloys were amorphized using either a melt-spinning or ball-milling process in a high-energy planetary mill. The elemental powders were initially blended to the desired composition (in at.%) of Zr, 65; Cu, 27.5; Al, 7.5 and of Ti, 25; Zr, 17; Cu, 29; Ni, 29, respectively. The composition of alloys was chosen to be the same as for the bulk amorphous ZrCuAl and easy glass-forming ZrNiTiCu alloys. An almost fully amorphous structure was obtained after 80 h of milling in the case of both compositions. Transmission electron microscopy studies of ball-milled powders revealed the presence of nano-crystallites [2-5 nm for ZrCuAl and smaller (1-3 nm) for the ZrTiNiCu alloy]. High-resolution transmission electron microscopy of melt-spun ZrNiTiCuAl ribbons provided evidence of the amorphous structure.

Journal Article↗

PubMed2006

Transmission electron microscopy studies of microstructure of Ti-Nb and Ti-Ta alloys after ball milling and hot consolidation.

Two Ti alloys with compositions Ti-10Ta and Ti-10Nb (at.%) were milled in a high-energy mill for a maximum of 80 h in an argon atmosphere. A nanocrystalline structure of alpha-Ti(X) (X = Ta or Nb) solid solution was formed in both investigated alloys after milling, as shown by X-ray diffraction. Transmission electron microscopy observations of powders milled for 80 h revealed chemical inhomogeneity of particles in nanometre-scale regions and an average crystallite size of about 10 nm. The pulse plasma sintering method was applied for hot consolidation of milled powders. The mean density of pulse plasma sintering compacts of Ti-Nb alloy was about 99.5% of the theoretical value, whereas the density of the Ti-10Ta sample was lower, close to 92% of the theoretical value. Transmission electron microscopy observation of compacted samples showed that the sintering process caused the formation of a two-phase alpha + beta structure in both investigated alloys, with a mean grain size of 220 nm. The chemical inhomogeneity and high degree of deformation in nanometre-scale regions of milled powders led to a martensitic transformation, resulting in formation of a 9R martensite structure.

Journal Article↗

PubMed2001

Occupational airborne contact dermatitis caused by thyme dust.

The aim of the study was to assess occupational hazards to the farmer's skin associated with processing thyme (Thymus vulgaris L.). 46 farmers were studied during the threshing of dried thyme. They were questioned about work-related skin problems and examined before and after work. In all persons, serum thyme-specific IgE was measured. Skin prick tests, the Ouchterlony test and the migration inhibition test were carried out with allergens of airborne bacteria and fungi present in the working environment. Of the 46 farmers studied, 4 showed skin symptoms after 5-30 min of exposure to thyme dust. Thyme-specific IgE was found in 1 person with work-related symptoms, but also in 2 asymptomatic farmers. Therefore, the importance of IgE seems to be questionable in eczema related to thyme dust. Skin and blood tests with microbial allergens also showed no significant differences between the symptomatic and asymptomatic farmers. To our knowledge, this is the 1st description of occupational airborne contact dermatitis caused by thyme dust. The etiology of thyme-related skin symptoms remains obscure, although an irritant mechanism seems probable.

Adult↗

PubMed2001

Work-related skin symptoms and type I allergy among eastern-Polish farmers growing hops and other crops.

UNLABELLED: 73 eastern-Polish farmers growing hops and other crops were examined. They were questioned by a dermatologist and subsequently skin prick-tested with allergens of hops, grain dust, straw dust, hay dust, storage mites, and antigens of microorganisms typical for farm environment. RESULTS: 14 farmers (19.2%) complained of work-related skin symptoms, caused most often by hops (11%), followed by grain (5.6%), hay (5.5%) and straw (4.1%). Five farmers (6.8%) complained of hand dermatitis, four (5.5%) of airborne dermatitis, and eight (11.0%) of pruritus. In two farmers, two skin diseases co-existed. The skin symptoms were mostly mild, however, one case of severe invalidating airborne dermatitis to hops was found. On skin prick tests, 14 farmers (19.2%) showed positive skin reaction to at least one allergen; 5.5% of farmers reacted to grain dust, 5.5% to straw dust, 11% to hay dust, and 8.2% to hops. Tests with storage mites showed positive reactions to Acarus siro in 9.6%, Lepidoglyphus destructor in 17.8%, and to Tyrophagus putrescentiae in 13.7%. Tests with microbial allergens elicited positive reactions to Pantoea agglomerans in 4.1%, Saccharopolyspora rectivirgula in 4.1%, Aspergillus fumigatus in 4.1% and to Streptomyces albus in 1.4% of farmers. Although results of skin prick tests in general did not correlate well with the work- related skin symptoms, in three of 14 farmers with skin symptoms the tests results played a crucial role in identifying the cause of their work-related skin disease.

Adult↗

PubMed2001

Exposure to airborne microorganisms in Polish sawmills.

Microbiological air sampling was performed in four sawmills located in eastern Poland, of which two were processing coniferous wood (pine, fir) and other two deciduous wood (oak, birch). Total concentration of microorganisms (bacteria and fungi) in the air of sawmills processing coniferous wood was on average 20.2 +/- 5.6 x 10(3) cfu/m(3) (mean +/- S.E.) and significantly (p < 0.05) higher compared to those processing deciduous wood where the mean concentration of airborne microorganisms was 9.8 +/- 3.0 x 10(3) cfu/m(3). The greatest concentrations of microorganisms in the sawmills processing coniferous wood were noted at debarking and at first-cut frame sawing of pine logs (42.1 +/- 7.6 x 10(3) cfu/m(3) and 39.8 +/- 7.0 x 10(3) cfu/m(3), respectively). Microflora released into air during debarking consisted mostly of allergenic fungi (mainly Aspergillus fumigatus) and corynebacteria, whereas airborne microflora recovered during first-cut frame sawing constituted mostly of endotoxin-producing Gram- negative bacteria of the genus Rahnella, developing in the sapwood of pine. In the sawmills processing deciduous wood, the largest concentration of microorganisms (30.6 +/- 3.4 x 10(3) cfu/m(3)) was found at sorting of the oak parquet boards and was due to the secondary infection of the boards with moulds Penicillium citrinum during prolonged storing in the open air. Values of the respirable fraction of airborne microflora in the examined sawmills varied within fairly wide limits and were between 22.5 86.6%. Altogether, 34 species or genera of bacteria and 21 species or genera of fungi were identified in the air of sawmills, of which respectively 13 and 9 species or genera were reported as having allergenic and/or immunotoxic properties. The concentrations of airborne bacterial endotoxin which were determined on two sampling sites in the sawmills processing pine and fir, were 0.24 microg/m(3) and 4.00 microg/m(3) respectively, distinctly exceeding the suggested safe level. In conclusion, the workers of Polish sawmills may be exposed on some working stands to airborne microorganisms posing respiratory hazard, of which the greatest risk is represented by allergenic fungi developing on bark of logs or stored wood products and endotoxin-producing Gram-negative bacteria of the genus Rahnella, developing in sapwood of coniferous logs

Air Microbiology↗

PubMed2001

Response of sawmill workers to work-related airborne allergens.

The aim of this work was to determine the reactivity of sawmill workers to biological allergens associated with wood dust. Allergological examinations by skin and precipitin tests were performed in 43 workers employed in a sawmill processing coniferous wood (pine), in 90 workers employed in two sawmills processing deciduous wood (oak), and in 32 healthy urban dwellers not exposed to organic dusts (referents). The skin test was performed by the intradermal method with the saline extracts of wood dust and of the cultures of three microbial species (Rahnella sp., Brevibacterium linens and Penicillium citrinum) isolated from the air polluted with wood dust. Sawdust from pine was used for testing of the pine processing workers and referents while sawdust from oak was used for testing of the oak processing workers. Skin reactions were recorded after 20 minutes, 8 hours and 24 hours. The agar-gel test for the presence of precipitins in serum was performed with the extract of pine wood dust and extracts of 17 microbial isolates. The workers processing pine showed a very high frequency of positive skin reactions to the extract of wood dust at all time intervals, significantly greater compared to the workers processing oak and referents (p < 0.001). The early skin reactions to the extracts of dust-borne bacteria and fungi were very common among sawmills workers and showed a significant relationship with the degree of exposure. The frequency of reactions to Gram-negative bacterium Rahnella sp. was significantly greater in the pine processing workers than in the oak processing workers and referents (p < 0.001). By contrast, the oak processing workers reacted significantly more frequently to Penicillium citrinum, compared to the pine processing workers and referents (p < 0.01). These results conform to the prior study of airborne microflora in which the dominancy of Gram-negative bacteria was stated in the pine processing sawmill while mould fungi were most common in the oak processing sawmills. The antibody response of sawmill workers to work-related antigens was much weaker compared to skin reactions. As many as 41 sawmill workers reported the occurrence of work-related symptoms. A significant relationship was found between the occurrence of symptoms and frequency of allergic reactions, but only with a limited number of antigens. The obtained results suggest that early allergic reactions to coniferous wood and to microorganisms associated with wood dust are common among sawmill workers, posing a potential risk of work-related disease in this occupational group.

Actinomycetales↗

PubMed2001

Exposure to airborne microorganisms in fiberboard and chipboard factories.

Microbiological air sampling was performed in one fiberboard factory and two chipboard factories located in south-eastern Poland. It was found that the levels of bacteria, fungi, dust and bacterial endotoxin in the air of examined facilities were high during initial stages of the production cycle (shredding of waste wood, storing of chips) and then sharply decreased during further stages of this cycle (forming and formatting of the boards). In the fiberboard factory, the concentration of airborne microorganisms at the initial stages of production cycle was 71.8-95.2 x 10(3) cfu/m3 and dropped in further stages to the level of 8.4-17.5 x 10(3) cfu/m3. Fungi (mostly Aspergillus fumigatus and Penicillium spp.) were prevailing microorganisms in the air of the fiberboard factory, forming 46.0-87.3% of the total airborne microflora. The concentrations of microorganisms in the air of the chipboard factories were significantly lower compared to the fiberboard factory (p<0.05). During initial stages of production cycle they were within the range of 12.9-101.5 x 10(3) cfu/m3, while during forming and formatting of boards within the range of 5.3-12.4 x 10(3) cfu/m3. On average, the most common microorganisms in the air of the chipboard factories were corynebacteria (mostly Arthrobacter spp. and Corynebacterium spp.) which formed 24.4-64.6% of the total microflora. The values of the respirable fraction of airborne microflora in the fiberboard and chipboard factories varied within a fairly wide range and were between 20.5-91.1%. Altogether, 38 species or genera of bacteria and 16 species or genera of fungi were identified in the air of examined factories, of which respectively 14 and 9 species or genera were reported as having allergenic and/or immunotoxic properties. The concentration of bacterial endotoxin in the air of examined factories was greatest, similarly to the concentration of microorganisms, during the initial stages of the production cycle: 103.1-1974.0 EU/m3 in the fiberboard factory, and 3.2-217.4 EU/m3 in chipboard factories. In conclusion, the workers of fiberboard and chipboard factories may be exposed during the initial stages of the production cycle (shredding of waste wood, storing of chips) to high levels of airborne microorganisms and endotoxin posing respiratory hazard.

Air Microbiology↗

PubMed2001

Exposure to airborne microorganisms and endotoxin in herb processing plants.

Microbiological air sampling was performed in two herb processing plants located in eastern Poland. Air samples for determination of the levels of bacteria, fungi, dust and endotoxin were collected at 14 sites during cleaning, cutting, grinding, sieving, sorting and packing of 11 kinds of herbs (nettle, caraway, birch, celandine, marjoram, mint, peppermint, sage, St. John's wort, calamus, yarrow), used for production of medications, cosmetics and spices. It was found that processing of herbs was associated with a very high pollution of the air with bacteria, fungi, dust and endotoxin. The numbers of microorganisms (bacteria and fungi) in the air of herb processing plants ranged within 40.6-627.4 x 10(3) cfu/m3 (mean +/- S.D = 231.4 +/- 181.0 x 10(3) cfu/m3). The greatest concentrations were noted at the initial stages of production cycle, during cleaning, cutting and grinding of herbs. The numbers of airborne microorganisms were also significantly (p<0.0001) related to the kind of processed herb, being the greatest at processing marjoram, nettle, yarrow and mint. The values of the respirable fraction of airborne microflora in the examined facilities varied within a fairly wide range and were between 14.7-67.7%. The dominant microorganisms in the air of herb processing plants were mesophilic bacteria, among which endospore-forming bacilli (Bacillus spp.) and actinomycetes of the species Streptomyces albus were most numerous. Among Gram-negative bacteria, the most common was endotoxin-producing species Alcaligenes faecalis. Altogether, 37 species or genera of bacteria and 23 species or genera of fungi were identified in the air of herb processing plants, of these, 11 and 10 species or genera respectively were reported as having allergenic and/or immunotoxic properties. The concentrations of dust and bacterial endotoxin in the air of herb processing plants were large with extremely high levels at some sampling sites. The concentrations of airborne dust ranged within 3.2-946.0 mg/m3 (median 18.1 mg/m3), exceeding at 13 out of 14 sampling sites the Polish OEL value of 4 mg/m3. The concentrations of airborne endotoxin ranged within 0.2-2681.0 microg/m3 (median 16.0 microg/m3), exceeding at all sampling sites the suggested OEL value of 0.1 microg/m3. In conclusion, the workers of herb processing plants could be exposed to large concentrations of airborne microorganisms, dust and endotoxin posing a risk of work-related respiratory disease.

Air Microbiology↗

PubMed2001

Enzymatic activities of Aspergillus fumigatus strains isolated from the air at waste landfills.

Out of 15 Aspergillus fumigatus strains isolated from the air at waste landfills, all revealed cellulolytic and lipolytic activities. Eleven out of 15 strains showed very strong cellulolytic properties, as assessed by the viscosimetric test for endo-1,4-beta-glucanase activity (EGA). None of the examined strains revealed a well-expressed proteolytic activity. The results suggest that Aspergillus fumigatus strains developing in stored wastes produce strong cellulotytic enzymes which need further studies for the potential allergenic and/or immunotoxic effects of these proteins on exposed workers.

Air Microbiology↗

PubMed2001

Young farmers with cellular reactivity to airborne microbes suffer more frequently from work-related skin symptoms and allergic dermatitis.

UNLABELLED: 75 farming students (49 males and 26 females aged 16-23 years) underwent dermatological, laryngological and pulmonary examination, skin prick tests with common and farm allergens, Phadiatop and total IgE measurement. After that, the migration inhibition tests with antigens of airborne microbes typical for farm environment (Saccharopolyspora rectivirgula, Pantoea agglomerans, and Aspergillus fumigatus) were carried out. Possible differences between students with positive results and those non-reactive were sought. RESULTS: 10 students reacted to at least one microbial antigen in the migration inhibition test. There were no significant differences in distribution of atopy, prick test results, total IgE, and Phadiatop between the reactive students and their classmates. Only one case of asthma was found, hence a further statistical analysis was not feasible. Allergic rhinitis has been found in 30% of the reactive and in 9.2% of non-reactive students; the difference, however, was not statistically significant (p=0.06). Significant differences were found with respect to the frequency of allergic skin diseases (40% reactive versus 9.2% non-reactive, p = 0.009); no other triggering factors than microbial antigens could be identified in 2 out of 4 reactive students with dermatitis. Work-related symptoms were present in all reactive students (100% versus 27.7%, p=0.001); 8 out of 10 reactive students did not show any other specific sensitisation. Antigens of airborne microbes are commonly associated with lung diseases. Our results, however, suggest that the skin may be affected as well. Relatively strong association between cellular reactivity to airborne microbes and skin diseases deserves further studies.

Adolescent↗

PubMed2001

Atopy, allergic diseases and work-related symptoms among students of agricultural schools: first results of the Lublin study.

136 eastern-Polish farming students (51 females and 85 males, aged 16-23 years) underwent clinical examination, skin prick tests with common and farm-specific allergens, total IgE measurement and Phadiatop test. Atopy was found in 35.3% (95% CI: 27.3-43.3%) of students. For allergic skin diseases, the point prevalence was 5.9%, the lifetime prevalence 28.7%; for allergic rhinitis 12.7% and 16.4%; for asthma 2.2% and 8.8% respectively. 56 students (41.2%) complained of work-related symptoms; most often of pruritus (30.9%), erythema of the skin (16.9%), sneezing (16.2%), rhinorrhea (15.4%), cough (9.6%) and dyspnea (8.1%). The students reported as causative factors of work-related symptoms: grain dust (71.4% of the 56 symptomatic students), hay dust (57.1%), straw dust (17.9%), green parts of plants (5.4%), fertilisers, diesel fuel and farm animals (3.6% each). Prick tests were positive in 30.9% of students, most frequently to Lepidoglyphus destructor (18.4% of all students), Tyrophagus putrescentiae (15.4%), Dermatophagoides pteronyssinus (14.0%), Acarus siro (13.2%) and weed pollens (5.1%). The only statistically significant difference between males and females found in the study was that in the lifetime prevalence of allergic skin diseases (males 17.6% versus females 47.1%, p<0.001). Students reporting work-related symptoms had significantly more present and past allergic skin diseases and allergic rhinitis (for each feature p<0.01), and past obstructive lung disease (p=0.001). In 12 farming students (8.8%, 95% CI: 4.1-13.6%), employment as a farmer was strongly contraindicated due to health status.

Adolescent↗

PubMed2001

Levels of fungi and mycotoxins in samples of grain and grain dust collected on farms in Eastern Poland.

Ten samples of stored wheat grain and 10 samples of settled grain dust released during machine threshing of wheat grain were collected on 10 farms located in Lublin province (eastern Poland). The samples were examined for the concentration of total microfungi, Fusarium species, fusariotoxins (moniliformin, deoxynivalenol, nivalenol), and ochratoxin. Microfungi able to grow on malt agar were present in 30% of grain samples (median for all examined samples = 0, range 0-227.5 x 10(3) cfu/g) and in all samples of grain dust (median = 977.5 x 10(3) cfu/g, range 115.0-16,700.0 x 10(3) cfu/g). Fusarium species (F. avenaceum) were found only in 10% of grain samples (median = 0, range 0-800.0 x 10(3) cfu/g), but in 90% of grain dust samples (median = 1,150 x 10(3) cfu/g, range 5.5-10,060.0 x 10(3) cfu/g). The species F. avenaceum, F. culmorum, F. graminearum, F. poae and F. sporotrichioides were isolated respectively from 50%, 10%, 20%, 40% and 20% of examined grain dust samples. The presence of the mycotoxins produced by Fusarium (moniliformin, deoxynivalenol, and nivalenol) was found altogether in 70% of wheat grain samples (median = 0.1275 microg/g, range 0-1.480 microg/g) and in 90% of grain dust samples (median = 0.350 microg/g, range 0-1.090 microg/g). Moniliformin (MON), deoxynivalenol (DON), and nivalenol (NIV) were each detected in 40% of grain samples, and respectively in 80%, 40%, and 40% of grain dust samples. Ochratoxin A (OTA) was detected in 60% of grain samples and in 60% of grain dust samples (median in both cases was 0.0005 microg/g). The concentrations of F. poae (p<0.05) and of total Fusarium species (p<0.01) in grain samples, and the concentrations of F. culmorum and F. graminearum (p<0.05) in grain dust samples were significantly correlated with the concentration of deoxynivalenol. The concentrations of F. poae (p<0.05) and of total Fusarium species (p<0.01) in grain dust samples were significantly correlated with the concentration of total fusariotoxins. Moreover, the concentration of total Fusarium species in grain dust samples was significantly correlated with the concentration of nivalenol (p<0.05). In conclusion, the majority of samples of wheat grain and grain threshing dust collected on farms in eastern Poland contained notable quantities of fusaria and/or fusariotoxins. This fact poses a potential risk of mycotoxicoses to agricultural workers exposed to grain dust when handling wheat during threshing, unloading, shuffling, and other farm occupations.

Agricultural Workers' Diseases↗

PubMed2001

Response of herb processing workers to work-related airborne allergens.

A group of 51 herb processing workers employed in a big herb processing facility located in eastern Poland were examined by the skin and precipitin tests with, respectively, 4 and 17 extracts of microorganisms associated with organic dusts. Out of this number, 32 workers were examined by the skin test with 7 extracts of selected herbs processed in the facility. All the subjects were asked about the occurrence of work-related symptoms. 32 healthy office workers were examined with microbial extracts as a reference group. The herb processing workers showed a high proportion of early skin reactions (after 20 min) to the extract of Gram-negative bacterium Alcaligenes faecalis (41.2%), significantly higher compared to the reference group (p<0.01). At all time intervals (20 min, 8 hrs, 24 hrs), the workers responded with a high frequency to the extract of Bacillus subtilis (respectively 72.5%, 64.7%, and 15.7%), significantly greater compared to the reference group (respectively p<0.001, p<0.001, and p<0.05). No significant differences were found between the groups of herb processing workers and referents in skin response to the extracts of Streptomyces albus and Alternaria alternata and, except for the extract of Pantoea agglomerans, in the frequency of positive precipitin reactions to microbial antigens. In the skin test with herb extracts, the highest response among workers were caused by the extracts of chamomile flowers and nettle leaves which evoked 40-65% of positive skin reactions at all time intervals. 39 out of 51 interviewed herb processing workers (76.5%) reported the occurrence of work-related general, respiratory and skin symptoms. The positive skin reactions occurred more frequently among symptomatic workers which suggests that the specific immunologic response might be implicated in etiopathogenesis of work-related symptoms in examined workers. However, in most cases the differences did not attain a significance level which indicates that there is no direct relationship between a positive immunologic response and the appearance of symptoms caused by occupational exposure to herb dust, and that most probably a considerable part of these symptoms might be also due to non-specific immunologic and/or toxic mechanisms.

Adult↗

PubMed2001

Preliminary studies on the relationship between Ixodes ricinus activity and tick-borne infection among occupationally-exposed inhabitants of eastern Poland.

Relative density (activity) of the tick Ixodes ricinus was determined in five districts of the Lublin region (eastern Poland) by vegetation flagging. Tick activity values were compared to the determined by ELISA tests seroprevalence to tick-borne encephalitis virus (TBEV) and Borrelia burgdorferi in forestry workers and farmers from the same areas. A significant correlation between tick activity and seroprevalence to both TBEV and B. burgdorferi antigen was found in farmers and in the total examined population.

Agricultural Workers' Diseases↗

PubMed2000

Occupational contact dermatitis to Phaseolus vulgaris in a farmer - a case report.

A case of occupational contact dermatitis in a farmer is described, caused among others by Phaseolus vulgaris. The patient's history of eczematous and vesicular and bullous skin reactions occurring after exposure to Phaseolus was confirmed by skin tests with native leaves of the plant. To the best of our knowledge, this is the first description of occupational contact dermatitis caused by leaves of Phaseolus plant.

Adult↗

PubMed2000

Aspergillus candidus: a respiratory hazard associated with grain dust.

The concentration of Aspergillus candidus in samples of grain dust and of air polluted with grain dust was found to be large (respectively 3.0 x 10(5) - 3.0 x 10(9) cfu/g and 5.0 x 10(3) - 6.47 x 10(5) cfu/m(3)) and proved to be significantly greater compared to samples of other organic dusts (p<0.001). Rabbits exposed to long-term inhalation of the cell extract of A. candidus revealed a positive cellular and humoral response, demonstrated by the significant (p<0.01) inhibition of leukocyte migration in the presence of specific antigen and by production of precipitins against antigen of the fungus. The inhibition of leukocyte migration was even stronger in another group of rabbits exposed twice to the inhalation of live A. candidus spores. A group of grain workers reacted significantly more frequently to extract of A. candidus in the leukocyte migration inhibition test (p<0.01) and precipitation test (p<0.05), compared to the control group not exposed to organic dusts. It was concluded that Aspergillus candidus, because of its common occurrence and strong immunomodulating properties, poses an important occupational hazard for grain handling workers

Adult↗

PubMed2000

Effects of exposure to flax dust in Polish farmers: work-related symptoms and immunologic response to microbial antigens associated with dust.

Medical examinations were performed in a group of 51 Polish farmers heavily exposed to flax dust during harvesting and scutching (threshing) and in a group of 50 healthy urban dwellers not exposed to organic dusts (controls). The examinations included: interview concerning the occurrence of respiratory disorders and work-related symptoms, physical examination, X-ray examination of chest, lung function tests, oxymetric examinations, determination of the concentration of cytokines (IL-1alpha IL-6, TNFalpha) in blood serum and allergological tests with microbial antigens associated with organic dust, comprising: skin prick test with 4 antigens, agar-gel precipitation test with 12 antigens and test for specific inhibition of leukocyte migration with 4 antigens. As many as 32 farmers (62.7%) reported the occurrence of work-related symptoms during harvesting, transporting and scutching of flax. The most common complaint was general weakness reported by 15 farmers (29.4%), followed by headache reported by 14 (27.5%), blocking of the nose - by 11 (21.6%), dry cough, shivering, and eyes itching - each by 10 (19.8%), chest tightness and hoarseness - each by 9 (17.6%). No control subjects reported these work-related symptoms. The mean spirometric values in the examined group of farmers were within a normal range and did not show a significant post-shift decline. In contrast, a significant post-shift decline of oxymetric values was found among flax farmers. The farmers showed a frequency of the positive early skin reactions to environmental allergens in the range of 0-19.6%, a frequency of positive precipitin reactions in a range of 0-56.9%, and frequency of positive reactions of leukocyte migration inhibition in a range of 7.8-21.6%. The members of the control group responded to the majority of allergens with a significantly lower frequency of positive results compared to the farmers. Elevated concentrations of IL-1alpha and IL-6, but not TNFalpha, were found in blood sera of flax farmers. In conclusion, farmers engaged in harvesting and scutching of flax represent a group of elevated professional risk because of high incidence of work-related symptoms and high frequency of allergic reactions to bacteria and fungi associated with organic dust.

Adult↗