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.

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.

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.

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.

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.

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

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.

[Microflora of the farming work environment as an occupational risk factor]. / Mikoflora rolniczego srodowiska pracy czynnikiem narazenia zawodowego.

The paper presents the results of the studies concerning the air mould fungi concentration in the work environment during grain threshing, flax breaking and thyme cleaning. A high level of fungi was observed in the air at all workplaces with the highest concentrations during grain threshing. Of the total number of 12 farms, in 8 the air mould fungi concentration exceeded the proposed standard of 50,000 CFU/m3. Among the species containing cereals, flax and thyme, mould fungi of Alternaria alternata sp.--an etiologic factor of allergic respiratory diseases--occurred most frequently. During flax breaking, the presence of fungi of Fusarium poae sp., which affect grain husks and cause a great economic loss in agriculture, was observed. Mould fungi of Aspergillus candidus sp. were found during thyme cleaning. These fungi have been reported to be an etiologic factor of organic dust toxic syndrome among secondary school students employed in the grain dust environment polluted with the spores of Aspergillus candidus. The results obtained show that the agricultural work environment is considerably polluted with the spores of mould fungi of allergenic and immunotoxic properties, which cause a high degree of health risk to people employed in agriculture.

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

Occupational biohazards in agricultural dusts from India.

Sixteen samples of settled dusts deposited during handling of various granular plant materials (green gram, red gram, amaranth, rice, pearl millet, sorghum, wheat, maize) in small food storing and processing facilities (godowns) were collected in the region of Aurangabad (Southern India). The samples were examined by the dilution plating method for the concentration and species composition of Gram-positive mesophilic bacteria, Gram-negative mesophilic bacteria, thermophilic actinomycetes and fungi. They were also examined by Limulus test for the concentration of bacterial endotoxin. The total concentration of microorganisms (bacteria + fungi) in examined samples varied within a wide range of 1.4 x 10(5) - 8.45 x 10(8) cfu/g (median 8.36 x 10(6) cfu/g). On average, the most common were Gram-positive bacteria (87.84% of all isolates) followed by Gram-negative bacteria (11.12%). Less common were fungi (1.24%) and thermophilic actinomycetes (0.01%). Among isolated bacteria and fungi, there were many species known as causative agents of allergic alveolitis, asthma and organic dust toxic syndrome. The concentration of bacterial endotoxin in the examined samples ranged between 12.5 - 62500 microg/g (median 781.25 microg/g), being particularly large in the samples of dust from maize (6250 microg/g and 62500 microg/g) and pearl millet (6250 microg/g and 12500 microg/g). The results of the present work indicate that the agricultural dusts from India represent a potential hazard for the workers because of high concentrations of allergenic microorganisms and bacterial endotoxin. The particular risk is associated with handing of maize and pearl millet. Further studies on this subject with the use of aerobiological methods are highly desirable

Allergic alveolitis due to herb dust exposure.

We report an episode of allergic alveolitis in a female farmer due to massive exposure to organic dust contaminated with microorganisms during threshing of herbs (thyme). The patient's medical history, the results of exposure test, inhalation challenge, and bronchoalveolar lavage suggested the diagnosis of allergic alveolitis

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

Medical examinations were performed in a group of 76 Polish farmers heavily exposed to grain dust during harvesting and threshing, and in a group of 63 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, lung function tests, and allergological tests comprising skin prick test with 4 microbial antigens associated with grain dust and agar-gel precipitation test with 12 microbial antigens. As many as 34 farmers (44.7%) reported the occurrence of work-related symptoms during harvesting and threshing. The most common was dry cough reported by 20 individuals (26.3%). Dyspnoea was reported by 15 farmers (19.7%), tiredness by 12 (15.7%), chest tightness by 8 (10.5%), plugging of nose and hoarseness by 5 each (6. 5%). No control subjects reported these work-related symptoms. The mean spirometric values in the examined group of farmers were within the normal range, but a significant post-shift decrease of these values was observed after work with grain. The farmers showed a frequency of the positive early skin reactions to environmental allergens in the range of 10.8 - 45.5%, and a frequency of positive precipitin reactions in range of 3.9 - 40.8%. The control group responded to the majority of allergens with a significantly lower frequency of positive results compared to the farmers. The obtained results showed a high response of grain farmers to inhalant microbial allergens and indicate a potential risk of occupational respiratory diseases (such as allergic alveolitis, asthma, Organic Dust Toxic Syndrome) among this population

[Microflora of the air in sawmills as a potential occupational hazard: concentration and composition of microflora and immunologic reactivity of workers to microbial aeroallergens]. / Mikroflora powietrza tartaków jako potencjalny czynnik zagrozenia zawodowego: stezenie i sklad mikroflory oraz immunologiczna reaktywnosc pracowników na aeroalergeny drobnoustrojowe.

Microbiologial studies of the air and allergological examinations of the workers were performed in two sawmills processing deciduous wood (mainly oak) and in one sawmill processing coniferous wood (mainly pine). The concentration of microorganisms in the air was of the order 10(3)-10(4) cfu/m3. The most common organisms were corynebacteria (Arthrobacter, Corynebacterium, Brevibacterium, Microbacterium), spore-forming bacilli (Bacillus), Gram-negative bacteria (rahnella) and filamentous fungi (Aspergillus, Penicillium). The workers responded to the extract of pine dust with much higher frequency than to the extract of oak dust. The workers processing pine were often sensitized to Rahnella while those processing oak were commonly sensitized to Penicillium. Precipitin reactions were rare and occurred only with the antigen of Rahnella.

[The effect of wood dust on the respiratory system. Medical examination of furniture factory workers]. / Wplyw pylu drzewnego na uklad oddechowy. Badania lekarskie pracowników zakladów meblarskich.

The medical-environmental questionnaire, physical examination and pre-shift and post-shift spirometry have been performed in 48 furniture factory workers. The workers showed the work-related symptoms: cough, shortness of breath, chest pain, headache, general malaise, skin symptoms, eye symptoms, rhinitis. No relationship was found between the spirometry values and the frequency of the symptoms. The exposed workers showed a significant post-shift reduction of the FVC, FEV1, FEV1%VC and PEF (p < 0.001). The higher drops of the spirometric parameters occurred in younger workers. The presented data show that processing of wood may be associated with the work-related respiratory symptoms and diseases in exposed workers.

[Microflora of the in furniture factors as a potential occupational hazard: concentration and composition of microflora and immunologic reactivity of workers to microbial aeroallergens]. / Mikroflora powietrza fabryk mebli jako potencjalny czynnik zagrozenia zawodowego: stezenie i skiad mikroflory oraz immunologiczna reaktywnosc pracowników na aeroalergeny drobnoustrojowe.

Microbiologial studies of the air were performed in two furniture factories. The concentration of microorganisms in the air was low, being of the order 10(3) cfu/m3. The most common organisms were corynebacteria (Arthrobacter, Corynebacterium, Brevibacterium, Microbacterium) and fungi (Aspergillus fumigatus, Rhodotorula rubra). Some of the species found in this environment possess known allergenic properties. Allergological examinations of the workers with environmental aeroallergens have been performed in three departments of one factory. The highest frequency of positive skin reactions were observed among the workers of the varnishing department which may be due to synergistic effects of chemical pollutants. The incidence of precipitin reactions was low among all workers.

[Contamination of archives by filamentous fungi and their evaluation for potential pathogenicity]. / Skazenie ksiegozbiorów archiwum grzybami plesniowymi oraz ocena ich potencjalnej patogennosci.

The results of microbiological examinations of dust samples collected from mortgage registers in the court archives are presented. In the samples examined filamentous fungi of Penicillium genus were observed as well as Cladosporium herbarum, Geotrichum candidum, Cephalosporium glutineum, Mucor racemosus, Trichoderma viride and Aspergillus niger. Filamentous fungi of Penicillium genus occurred in the highest concentration accounting for 350,000 CFU/g. The levels of the remaining fungi were lower--they ranged from 500 CFU/g to 100,000 CFU/g. The concentration of filamentous fungi observed in archives can create health risk for workers.