Mycobiota and mycotoxins in various kinds of vegetables and fruits as potential health risk factors for consumers - summary of a multiyear study.

INTRODUCTION: Between 2015-2020, the concentrations and diversity of filamentous fungi as well as the levels of mycotoxins in 4 classes of vegetables and fruits were studied in samples from farms located in eastern Poland. The short communication summarizes the results with the use of statistical analysis and indicates the potential health hazards associated with the consumption of the produce contaminated with fungi and/or mycotoxins. The concentrations of filamentous fungi in all examined samples were moderate (2.813 - 4.146 log10 CFU g -1). The highest values were noted in root vegetables, whereas the lowest values in fruit vegetables. The mycobiota revealed a marked biodiversity (67 species and 33 genera). Penicillium and Fusarium prevailed in the mycobiota of root vegetables, whereas Cladosporium and Alternaria in the remaining classes. Most of identified species (88.1%) were described as potentially pathogenic. The importance of mycotoxins as a potential health risk factor for vegetable consumers, was confirmed by the detection of a high prevalence (>55%) of total aflatoxin (AFT). The level of AFT in berry fruits was significantly higher than in other classes. The high prevalence (58.5%) of deoxynivalenol was noted in raspberries. CONCLUSIONS: Filamentous fungi present in the examined vegetables and fruits may pose a potential health risk for consumers due to a high prevalence of potentially pathogenic species, mostly those producing mycotoxins.

Mycobiota of berry fruits - levels of filamentous fungi and mycotoxins, composition of fungi, and analysis of potential health risk for consumers.

INTRODUCTION AND OBJECTIVE: The aim of the study was to determine the presence, concentration and generic composition of filamentous fungi. Selected mycotoxins were also determined: total aflatoxins and deoxynivalenol. MATERIAL AND METHODS: In 2017-2018, 40 samples of strawberry fruits and 40 samples of red raspberry fruits were collected. In 2019-2020, 37 samples of fresh strawberry fruits and 41 samples of fresh red raspberry fruits were collected on conventional farms located in eastern Poland and were subjected to mycological examination. The concentration and species composition of filamentous fungi were determined by the method of plate dilutions on malt agar. The isolated strains were identified using macroscopic and microscopic methods. Samples were also analysed for the presence of aflatoxin B1, total aflatoxin and deoxynivalenol using ELISA tests. RESULTS: The median concentrations of fungi were moderate or low: 3.079 and 3.491 log10 CFU g-1 for strawberries and raspberries, respectively. Fungi of the genus Cladosporium prevailed in the mycobiota of berry fruits, accounting for 84.3% of total isolates in raspberries and 34.8% in strawberries. The occurrence of total aflatoxins was detected in the majority of tested samples (73.2% in raspberries and 70.3% in strawberries) but never exceeded the level of 4.0 µg kg-1 assumed as safe. Deoxynivalenol has been detected only in raspberries with the prevalence of 58.5%. Its median concentration was 242.0 µg kg-1 and in 7 out of 41 samples (17.0%) exceeded the level of 750.0 µg kg-1, assumed as safe. CONCLUSIONS: Filamentous fungi and mycotoxins occurred in the examined berries at levels that mostly do not represent a health risk for immunocompetent people, but might pose such risk for immuno-compromised and/or atopic consumers.

Levels of filamentous fungi and selected mycotoxins in leafy and fruit vegetables and analysis of their potential health risk for consumers.

INTRODUCTION AND OBJECTIVE: The aim of the study was to determine the presence, concentration and generic composition of filamentous fungi. Considering the significant role of mycotoxins in the pathogenicity of fungal contaminants of vegetables, the scope of the study was extended by determination of aflatoxins and deoxynivalenol. MATERIAL AND METHODS: In the years 2019-2020, samples of vegetables (lettuce, spinach, tomato, red pepper) collected on conventional farms located in eastern Poland were subjected to mycological examination. The concentration and species composition of filamentous fungi were determined by the method of plate dilutions on malt agar. The isolated strains were identified with the use of macroscopic and microscopic methods. Samples were also analyzed for the presence of aflatoxin B1 (AFB1), total aflatoxin (AFT) and deoxynivalenol (DON) using the immunoenzymatic ELISA method. RESULTS: The median concentrations of filamentous fungi ranged from 2.778-3.204 log10 CFU g -1. Overall, 40 fungal species were identified in the examined vegetables, of which 38 are classified as potentially pathogenic for humans. The mean prevalence values for AFB1 and AFT were moderate or high (16.0-60.0% and 57.8-75.6%, respectively) and very low for DON (0-2.2%). The median concentrations of filamentous fungi, AFB1 and AFT were distinctly greater in leafy vegetables than on non-leafy tomato and pepper fruits, and the differences were highly significant (P<0.001). CONCLUSIONS: The levels of filamentous fungi and mycotoxins in Polish vegetables could be classified as moderate or low. The abundant presence of species with various pathogenic abilities may pose a risk for some categories of people consuming raw vegetables, mostly for immuno-compromised persons or atopics susceptible to food allergy caused by ingested moulds.

The effect of fruit on the extracellular enzyme profiles of fungi.

INTRODUCTION: In recent years, the number of diseases caused by fungal pathogens has increased significantly. Many species of fungi are pathogenic for plants, causing a threat to food production and to humans, and are among the causes of chronic diseases. OBJECTIVE: The aim of the study is to determine the enzyme profiles of fungi, depending on the different types of fruit with which they have contact, and to determine the differences in these profiles in relation to the substrate on which they are grown. MATERIAL AND METHODS: Six strains of fungi identified as Cladosporium sphaerospermum, Fusarium poae, Alternaria alternata, Penicillium expansum, Penicillium verucosum and Acremonium strictum, isolated from fruits, were selected and analyzed for enzymatic profiles. The enzymatic activity was assessed using the API ZYM test (bioMerieux, France). RESULTS: In the majority of the 6 fungal strains isolated from fruits, enzymes belonging to glycol-hydrolases were the most active. The exception was Acremonium strictum, where phosphatases dominated. Among most fungal isolates, the enzymes ß- glucosidase and N-acetyl-ß-glucosaminidase showed the highest activity. The highest ß-glucosidase activities were found in Cladosporium sphaerospermum and Penicillium expansum. On the other hand, lipase, α-fucosidase and α-chymotrypsin showed the least activity. The least activity of these enzymes or their complete absence was observed in Fusarium poae, Alternaria alternata, Penicillium expansum and Acremonium strictum. CONCLUSIONS: The activity of hydrolytic enzymes in the isolated fungi depended on the addition of fruit and the type of medium. Individual fruits can increase or decrease the activity of the enzymes. Fungi present in fruit have pathogenic properties and can be possible risk factors for fungal infections.

Acute hypersensitivity pneumonitis in woodworkers caused by inhalation of birch dust contaminated with Pantoea agglomerans and Microbacterium barkeri.

CASE DESCRIPTION: Five workers (2 males and 3 females) employed in a furniture factory located in eastern Poland developed hypersensitivity pneumonitis (HP) after the pine wood used for furniture production was replaced by birch wood. All of them reported onset of respiratory and general symptoms (cough, shortness of breath, general malaise) after inhalation exposure to birch dust, showed crackles at auscultation, ground-glass attenuations in HRCT examination, and lymphocytosis in the BAL examination. The diagnosis of acute HP was set in 4 persons and the diagnosis of subacute HP in one. IDENTIFICATION OF SPECIFIC ALLERGEN: Samples of birch wood associated with evoking disease symptoms were subjected to microbiological analysis with the conventional and molecular methods. Two bacterial isolates were found to occur in large quantities (of the order 108 CFU/g) in examined samples: Gram-negative bacterium of the species Pantoea agglomerans and a non-filamentous Gram-positive actinobacterium of the species Microbacterium barkeri. In the test for inhibition of leukocyte migration, 4 out of 5 examined patients showed a positive reaction in the presence of P. agglomerans and 2 in the presence of M. barkeri. Only one person showed the presence of precipitins to P. agglomerans and none to M. barkeri. In the inhalation challenge, which is the most relevant allergological test in the HP diagnostics, all patients reacted positively to P. agglomerans and only one to M. barkeri. The results indicate that P. agglomerans developing in birch wood was the main agent causing HP in the workers exposed to the inhalation of dust from this wood, while the etiologic role of M. barkeri is probably secondary. CONCLUSION: The results demonstrate that apart from fungi and filamentous actinobacteria, regarded until recently as causative agents of HP in woodworkers, Gram-negative bacteria and non-filamentous actinobacteria may also elicit disease symptoms in the workers processing wood infected with large amounts of these microorganisms. The results obtained also seem to indicate that cellular-mediated reactions are more significant for causing disease symptoms compared to those that are precipitin-mediated.

Fungal diversity of root vegetables and soil rhizosphere collected from organic and conventional farms in Eastern Poland.

OBJECTIVE: Determination of the concentration and species composition of filamentous fungi in root vegetables (carrots and red beetroots), and the adjacent rhizosphere soil, collected on organic and conventional farms in Eastern Poland. MATERIAL AND METHODS: During the period 2015-2016, a total number of 80 samples of vegetables and 40 samples of soil were examined. From each type of farm, 20 samples of vegetables and 20 samples of the adjacent soil were examined. In addition, the study included 20 samples of vegetables from organic farms and 20 samples of vegetables from conventional farms purchased on the markets in the city of Lublin in Eastern Poland. In order to determine the concentration and species composition of filamentous fungi, both in vegetables and soil, the method of plate dilutions on Malt Agar medium (Difco) with chloramphenicol was used. The study was conducted in two parallel repetitions. Inoculated media were incubated at the temperature of 30° C for 72 hours, then at room temperature for 72 hours. The species composition of fungal flora was determined using macroscopic and microscopic methods, with the help of keys and atlases. RESULTS: It was found that the mean concentration of fungi was higher in vegetables and soil from conventional farms than in those from organic farms. In the case of carrots and soil from conventional farms, this concentration was 4.93 and 5.10 log10 CFU g-1, respectively, whereas from organic farms - respectively, 3.81 and 4.20 log10 CFU g-1. In the case of beetroots and soil from conventional farms, the mean concentrations were also higher compared to organic farms - 5.09 vs. 3.93 and 4.95 vs. 4.23 log10 CFU g-1. In the examined vegetables and rhizosphere soil, 61 species of filamentous fungi were found, of which 12 belonged to the genus Penicillium, 4 to the genus Fusarium, and 2 species each to the genera: Aspergillus, Cladosporium and Trichoderma. As many as 28 (45.9%) fungal species that occurred in vegetables and soil are regarded as pathogenic for humans.

Microbiological characterization of vegetables and their rhizosphere soil in Eastern Poland.

The aim of this study was to investigate the bacteriological quality of 5 kinds of vegetables (lettuce, dill, radish, beetroot, carrot) and their rhizosphere soil, originating from conventional farms located in the Lublin Province of Eastern Poland. A total number of 35 samples of fresh vegetables (FV) taken immediately from soil, 35 samples of soil from rhizosphere of these vegetables (SR) and 35 samples of vegetables sold at retail in the markets in Lublin (VR) were examined. The samples were analysed for the content of: aerobic mesophilic bacteria (AMB) grown at 30°C and 37°C, Gram-negative bacteria of Enterobacteriaceae family, faecal coliform (FC) bacteria, Salmonella spp., and Clostridium perfringens. Median AMB values determined at 30°C for FV, SR and VR were 5.27, 5.00, and 5.00 log10 CFU g-1 , respectively, being significantly greater compared to those recorded at 37°C. The exceeding of the threshold value of 6.0 log10 CFU g-1 proposed by Gelosa (1998) was noted only in 5 FV samples grown at 30°C (14.3%), and in 3 FV samples grown at 37°C (8.6%). The threshold value was never exceeded in SR and VR samples. Median concentrations of Enterobacteriaceae determined for FV, SR and VR were 4.03, 3.87, and 3.04 log10 CFU g-1, respectively. Eleven species of Enterobacteriaceae were identified in the FV, SR and VR samples. The percent of samples containing Escherichia coli was greatest for VR (22.9%), smaller for FV (17.1%) and smallest for SR (5.7%). The median concentrations of the faecal coliform bacteria (FC), determined by culture at 44°C, were low, amounting to 1.000 log10 CFU g-1 for FV and SR and 0.00 for VR. All examined vegetable and soil samples tested negative for the presence of Salmonella. The median concentrations of Clostridium perfringens were low, amounting to 0.00 log10 CFU g-1 for all categories of samples. This bacterium was relatively common in soil samples with the prevalence of 40.0%, but very rare in vegetable samples (occurring in 5.7% of FV and in none of VR samples). In conclusion, the results of the present study generally indicate that the microbiological quality of Polish vegetables grown on conventional farms is satisfactory and safe for consumers.

Enzymatic activity of fungi isolated from crops.

AIM: To detect and assess the activity of extracellular hydrolytic enzymes and to find differences in enzymograms between fungi isolated from wheat and rye samples and grown on Czapek-Dox Broth and Sabouraud Dextrose Broth enriched with cereal (wheat or rye). Isolated strains were also classified in the scale of biosafety levels (BSL). MATERIAL AND METHODS: The study used 23 strains of fungi cultured from samples of wheat and rye (grain, grain dust obtained during threshing and soil) collected in the Lublin region (eastern Poland). API ZYM test (bioMérieux) was carried out according to the manufacturer's instructions. Classification of BSL (Biosafety levels) was based on the current literature. RESULTS: High enzymatic activity was found in strains cultured in media containing 1% of wheat grain (Bipolaris holmi, Penicillium decumbens) and with an addition of 1% of rye grain (Cladosporium herbarum, Aspergillus versicolor, Alternaria alternata). The total number of enzymes varied depending on the type of media, and in most cases it was higher in the culture where an addition of cereal grains was used. CONCLUSIONS: Isolated strains of fungi reveal differences in the profiles of the enzyme assay. It can be assumed that the substrate enriched in grains stimulate the higher activity of mold enzymes.

Age influence on mice lung tissue response to Aspergillus fumigatus chronic exposure.

INTRODUCTION AND OBJECTIVE: Exposure to conidia of Aspergillus fumigatus was described as a causative factor of a number of the respiratory system diseases, including asthma, chronic eosinophilic pneumonia, hypersensitivity pneumonitis and bronchopulmonary aspergillosis. The study investigates the effects of the repeated exposure to A. fumigatus in mice pulmonary compartment. Our work tackles two, so far insufficiently addressed, important aspects of interaction between affected organism and A. fumigatus: 1) recurrent character of exposure (characteristic for pathomechanism of the abovementioned disease states) and 2) impact of aging, potentially important for the differentiation response to an antigen. MATERIALS AND METHODS: In order to dissect alterations of the immune system involved with both aging and chronic exposure to A. fumigatus, we used 3- and 18-month-old C57BL/6J mice exposed to repeated A. fumigatus inhalations for 7 and 28 days. Changes in lung tissue were monitored by histological and biochemical evaluation. Concentration of pro- and anti-inflammatory cytokines in lung homogenates was assessed by ELISA tests. RESULTS AND CONCLUSIONS: Our study demonstrated that chronic inflammation in pulmonary compartment, characterized by the significant increase of proinflammatory cytokines (IL1, IL6, IL10) levels, was the dominant feature of mice response to repeated A. fumigatus inhalations. The pattern of cytokines' profile in the course of exposure was similar in both age groups, however in old mice the growth of the cytokines' levels was more pronounced (especially in case of IL1).

Prevalence of antibodies against selected zoonotic agents in forestry workers from eastern and southern Poland.

INTRODUCTION AND OBJECTIVE: Due to the nature of their work, foresters are exposed to many infectious pathogens from the wildlife reservoir. The primary aim of this study was to assess their contact with these pathogens. MATERIAL AND METHODS: Sera and antibodies, mainly of IgG class against selected infectious factors, collected from a group of 216 employees of National Forests from eastern and southern Poland, were investigated. RESULTS: Antibodies to Anaplasma phagocytophilum were detected in 64 sera (29.6%), to Bartonella spp. in 133 sera (61.6%), to Babesia microti in 50 sera (23.1%), and to Coxiella burnetii in 14 sera (6.4%); 7 sera (3.2%) were positive to Francisella tularensis. In studies of diseases not carried by ticks positive results were found in 28 sera (12.9%) to Toxocara canis, 13 sera (6.0 %) to Trichinella spiralis, and in 7 sera (3.2%) to Echinococcus granulosus. Antibodies to Hanta viruses were detected with antigens from Puumala and Dobrava/Hantaan strains in both IgM and IgG class. In 9 foresters, positive results were found, including one positive result to 2 antigens, 5 to Dobrava/Hantaan antigen and 3 to Puumala antigen. CONCLUSION: Frequently higher percentages of positive results were found in people working utdoors, and in men when compared with women.

Allergy to selected cosmetic ingredients.

In an era in which cosmetics are commonly used, their often prolonged contact with the human body should determine the safety of their use. Often cosmetics are the cause of many side effects, mainly hypersensitivity reactions. Common groups of cosmetic components responsible for side effects are fragrances, preservatives and dyes. This paper focuses on the most allergenic components.

Assessment of microbiological cleanness of selected medicinal herbs in relations to the level of resource fragmentation.

Herbs are commonly used in the food and pharmaceutical industries. Their vast use is connected with their antibacterial or antioxidising properties, as well as numerous pro-health properties. The aim of the presented research was assessment of the quantitative and qualitative composition of moulds which contaminate samples of dried herbs: Sage (Salvia officinalis L.), Camomile (Matricaria chamomilla L.) and Melissa (Mellisa officinalis L.) with different degrees of resource fragmentation. The dried herbs investigated had a characteristic mould content below 1•10(6) CFU/g according to the recommendations of the European Herbal Infusions Association (EHIA). The most contaminated resource turned out to be Camomile, the least--Melissa. The most often isolated moulds were: Aspergillus, Penicillium, Ulocladium, Alternaria. Moreover, it was observed that more fragmented dried herbs were characteristic of lower--by approx. 40-55% microbiological contamination--depending on the type of tested herb, which might be connected with the time of dried herbs' processing, higher aeration, moisture changes or mechanical damaging of fungi's fragments in the case of a resource with higher fragmentation. High contamination of a herbal resource might be harmful for a consumer, and moulds and their metabolites in the form of mitotoxins might constitute a threat for human health. To keep all the sensory features and activity of herbs' active substances, it is extremely important to secure their high microbiological quality.

Age influence on hypersensitivity pneumonitis induced in mice by exposure to Pantoea agglomerans.

Hypersensitivity pneumonitis (HP) represents the immunologically mediated lung disease induced by repeated inhalations of a wide variety of certain finely dispersed organic antigens. In susceptible subjects, these inhalations provoke a hypersensitivity reaction characterized by intense inflammation of the terminal bronchioles, the interstitium and the alveolar tree. The inflammation often organizes into granulomas and may progress to pulmonary fibrosis. Our previous work indicated that cell extract of gram-negative bacteria Pantoea agglomerans (SE-PA) causes, in young C57BL/6J mice, pulmonary changes that are very similar to the clinical manifestations of HP in men. The purpose of presented studies was to describe the response of mice immune system while exposed to SE-PA. Particular attention was paid to examine the age influence on SE-PA induced inflammation and fibrosis in lung tissue. We used 3- and 18-month-old C57BL/6J mice. Lung samples were collected from untreated mice and animals exposed to harmful agent for 7 and 28 days. HP development was monitored by histological and biochemical evaluation. Using ELISA tests, we examined concentration of pro- and anti-inflammatory cytokines in lung homogenates. Our study demonstrated again that SE-PA provokes in mice changes typical for the clinical picture of HP, and that successive stages of disease (acute, subacute and chronic) might be obtained by modulation of time exposure. Furthermore, we found that animals' age at the time of sensitization influences the nature of observed changes (cytokine expression pattern) and the final outcome (reaction intensity and scale of fibrosis).

Grain dust originating from organic and conventional farming as a potential source of biological agents causing respiratory diseases in farmers.

INTRODUCTION: Agricultural producers are exposed to a number of different health risks associated with their work environment. AIM: The objective of the study was to assess the degree of colonization by fungi in terms of quantity and in terms of variety of species the samples taken from the settled dust from combine threshing of rye cultivation from organic and conventional farms in the Province of Lublin. MATERIAL AND METHODS: This paper is a preliminary quantitative assessment of the species of fungi colonizing the samples of settled dust collected during combine threshing from organic and conventional farms in the Province of Lublin. One of the stages of the project was the classification of biosafety BSL (biosafety level) of selected isolates and API ZYM tests to evaluate the potential ability of isolates to cause adverse health effects. To determine the concentration and composition of fungi in collected samples plate dilution method was used with two media: Malt Agar and Potato Dextrose Agar. RESULTS: MOST COMMONLY ISOLATED FUNGI IN SETTLED DUST SAMPLES COLLECTED DURING COMBINE THRESHING FROM ORGANIC FARMS, ON PDA MEDIUM WERE: Alternaria alternata and Aureobasidium pullulans. Cultures on MA medium were dominated by Alternaria alternata, Mycelia sterilia and Fusarium poae. In samples of dust from conventional crops, the predominant species was Alternaria alternata on PDA medium and on MA medium. CONCLUSIONS: The obtained results show a potential risk of people involved in agricultural work.

Rye grains and the soil derived from under the organic and conventional rye crops as a potential source of biological agents causing respiratory diseases in farmers.

INTRODUCTION: Due to the specific work environment, farmers are exposed to various biological occupational hazard. Among these factors significant are fungi present in the grain and also in the soil. The fungi may be the cause of human diseases including skin infections, asthma, allergic rhinitis and many others. AIM: The aim of this study was to quantify and identify species of fungi colonizing rye grain samples and the soil under cultivation. MATERIAL AND METHODS: THE MATERIAL CONSISTED OF GRAIN AND SOIL SAMPLES FROM TWO AGRICULTURAL SYSTEMS: organic and conventional. To determine the concentration and composition of fungi in collected samples, two media: Malt Agar (MA, Becton, Dickinson and Company) and Potato Dextrose Agar (PDA, Becton, Dickinson and Company) were used. The composition of species in fungal flora was determined using macroscopic and microscopic methods. The isolates of fungi were ranked in the appropriate classes of biosafety BSL. RESULTS: THE MOST FREQUENTLY ISOLATED FUNGI FROM ORGANIC RYE GRAIN, REGARDLESS OF THE MEDIA USED, WERE SPECIES: Aureobasidium pullulans and Alternaria alternata. In conventional farms, most species isolated from rye grain were: Aureobasidium pullulans, Cladosporium oxysporum, Alternaria alternata and yeast-like fungi. Most often species isolated from the soil was Penicillium citreo-viride. CONCLUSIONS: All the results of the research demonstrate the potential hazard to the health of people working in agriculture. Significant exposure of this professional group is associated with the presence of harmful biological agents present in the grain and soil from its cultivation.

Mouse model of hypersensitivity pneumonitis after inhalation exposure to different microbial antigens associated with organic dusts.

The aim of this study was to reproduce in laboratory conditions hypersensitivity pneumonitis (HP) pathogenesis in a new animal model predictive of the human response, and to select the microbial antigen associated with organic dust that exerts the strongest pathogenic effect on the respiratory organ. To achieve this goal, mice of the strain C57BL/6J prone to fibrosis were exposed for 1 hour daily up to 28 days to the inhalation of aerosols of each of the 5 microbial components of organic dusts whose conjunction with the occurrence of HP has been confirmed by numerous authors: Pantoea agglomerans saline extract (SE), P. agglomerans microvesicle-bound endotoxin, Saccharopolyspora rectivirgula SE, Aspergillus fumigatus SE, saline extract of dust from a grain sample overgrown with S. rectivirgula and Thermoactinomyces vulgaris, and a saline solvent (PBS) was used as a control. Exposure of the animals to organic dust components was conducted using a novel inhalation challenge set. Lung samples were collected from untreated mice and from mice exposed for 7 and 28 days, and examined by digitalized histopathology and biochemistry for the presence of inflammatory changes and fibrosis. P. agglomerans SE appeared to be the sole antigen which evoked a statistically significant fibrosis and a significant increase of hydroxyproline in the lungs of mice exposed for 28 days to this extract, both compared to the mice untreated and to those exposed to the solvent. P. agglomerans SE also evoked the strongest and statistically significant inflammatory response in the lungs of the mice, both after 7 and 28 days of exposure. After 7 days, significant inflammatory changes were also found in mice exposed to A. fumigatus SE, and after 28 days in mice exposed to all antigens. In conclusion, our results allow us to define a useful animal model of HP which can be a supplement for now commonly used bleomycin model. This model should comprise: present set of instruments for inhalation, mice of the line C57BL/6J and the saline extract of P. agglomerans as the antigen. For a better understanding of the presented results, a detailed study covering immunological investigations, focused on the mechanism of antigen action, are needed.

Occupational exposure to organic dust, microorganisms, endotoxin and peptidoglycan among plants processing workers in Poland.

The objective of present work was to determine and compare the components of bioaerosol in several sectors of plant processing industries. The study was conducted in 10 facilities engaged in herb and grain processing, flax threshing, grain storing, baking, and cereals production. The air samples were taken on glass fibre filters with an AS-50 sampler. We determined the concentrations of airborne microorganisms, dust, endotoxin and peptidoglycan. Total concentrations of viable airborne microorganisms ranged from 0.18-861.4 x 10(3) cfu/m(3). The highest levels of microbial contamination of the air were observed at flax farms, in grain elevators and in a herb processing plant. Gram-positive bacteria and fungi were detected at all sampling sites and their median concentrations were respectively 18.1 x 10(3) cfu/m(3) and 0.66 x 10(3) cfu/m(3). The concentration of Gram-negative bacteria ranged from 0.0-168.0 x 10(3) cfu/m(3). The concentration of thermophilic actinomycetes ranged from 0.0-1.45 x 10(3) cfu/m(3). Qualitatively, Gram-positive bacteria constituted 23-93% of the total microbial count. The most common species were: Staphylococcus spp., Curtobacterium pusillum, Rhodococcus fascians, Aureobacterium testaceum, Sanguibacter keddieii, Microbacterium spp., and Bacillus spp. Gram-negative bacteria formed 0-48% of the total count. The species Pantoea agglomerans dominated in all examined air samples. Fungi constituted 2.5-76.9% of the total microbial count. Among them, Penicillium spp., Mucor spp., Alternaria spp., Aspergillus niger, and Aspergillus spp. were found. The dust concentration ranged from 0.18-86.9 mg/m(3). The concentration of endotoxin was large and ranged from 0.0041-1562.6 microg/m(3). Muramic acid, the chemical marker of peptidoglycan, was detected in 9 out of 13 (69.2%) collected samples. The concentration of peptidoglycan ranged from 1.93-416 ng/m(3). A highly significant correlation was found between the individual components of bioaerosol determined in this study. The concentration of endotoxin was correlated with the concentration of Gram-negative bacteria, total microorganisms, and peptidoglycan (R>0.9, p<0.001). The concentration of peptidoglycan was correlated with the concentration of Gram-positive bacteria, Gram-negative bacteria, and total microorganisms (R>0.9, p<0.001).

Respiratory disorders in two workers of customs depositories occupationally exposed to mouldy tobacco.

Work-related respiratory symptoms, including dyspnoea, cough, fever, tiredness and malaise, were recorded in two customs officers employed in 2 depositories of confiscated cigarettes, of which one showed signs of dampness. Microbiological sampling of the air and the cigarettes stored in a damp depository revealed the presence of potentially pathogenic fungi and bacteria and the biochemical markers of bacterial lipopolysaccharide and fungal biomass. The Penicillium species (P. simplicissimum, P. inflatum, P. commune) dominated in the damp depository, while in the other one Aspergillus fumigatus was prevalent. The patients under study did not show a specific sensitization to microbial allergens in the precipitin test, the test for inhibition of leukocyte migration and the bronchial provocation challenge, except for a weak reaction to fungal allergens in the test for inhibition of leukocyte migration. Moreover, one patient responded with subjective symptoms after exposure to inhalation of increased doses of Penicillium simplicissimum antigen. Both cases were diagnosed as a specific form of organic dust toxic syndrome (ODTS). It is hypothesized that the symptoms were evoked most probably by the non-specific action of low molecular fungal metabolites, such as mycotoxins or VOCs (volatile organic compounds), with the possible contribution of bacterial endotoxin. However, as there is no a direct proof to support this presumption, and the effects of nicotine and other tobacco constituents cannot be excluded, further studies are needed to elucidate etiopathogenesis of the disorders associated with the exposure to stored tobacco.

Efficacy of a novel biofilter in hatchery sanitation: I. Removal of airborne bacteria, dust and endotoxin.

A novel biofilter containing organic, bentonite and halloysite media was applied for elimination of microbial pollutants from the air of an industrial hatchery. The concentrations of total mesophilic bacteria, Gram-negative bacteria, thermophilic actinomycetes, dust and bacterial endotoxin were determined in the air of hatchery during 2 months before installation of the biofilter, and during 6 months after installation of the biofilter, at the inlet and outlet ducts from each medium. Before installation of the biofilter, the concentrations of total mesophilic bacteria, Gram-negative bacteria, thermophilic actinomycetes, dust and endotoxin in the air were within the ranges of 0.97-131.2x10(3) cfu/m3, 0.0-34.4x10(3) cfu/m3, 0.0-0.02x10(3) cfu/m3, 0.37-4.53 mg/m3, and 50.9-520,450.4 ng/m3, respectively. Enterococcus faecalis and Gram-negative bacteria (Acinetobacter spp., Escherichia coli, Enterobacter cloacae, and other species) prevailed among bacterial species recovered from the air of the hatchery. A total of 56 species or genera of bacteria were identified in the air samples taken in the examined hatchery; of these, 11, 11 and 6 species or genera respectively were reported as having allergenic, immunotoxic and/or infectious properties The concentrations of total mesophilic bacteria, Gram-negative bacteria, Enterococcus faecalis and endotoxin found at the inlet duct of the biofilter after its installation were significantly smaller compared to those recorded before its installation (p<0.05). The concentrations of Gram-negative bacteria, Enterococcus faecalis and dust found at the outlet ducts of biofilter after its installation were significantly smaller compared to those recorded at the inlet duct of the biofilter (p<0.01). The concentrations of total meso-philic bacteria were also smaller at the outlet ducts of the biofilter compared to that at the inlet duct; however, the difference was not significant because of the massive growth of Streptomyces species in the biofilter's media which contaminated the outcoming air. In conclusion, the applied biofilter proved to be effective in the elimination of potentially pathogenic bacteria, dust and endotoxin from the air of the hatchery. The efficacy of the biofilter could be improved by the inhibition of the Streptomyces growth in the media of the biofilter.

Efficacy of a novel biofilter in hatchery sanitation: II. Removal of odorogenous pollutants.

The present research assessed the treatment efficiency of odorogenous pollutants in air from a hatchery hall vented on organic and organic-mineral beds of an enclosed-container biofilter. In this study, the following media were used: organic medium containing compost and peat (OM); organic-mineral medium containing bentonite, compost and peat (BM); organic-mineral medium containing halloysite, compost and peat (HM). The concentration of odorogenous gaseous pollutants (sulfur compounds and amines) in the hatching room air and in the air after biotreatment were determined by gas chromatography. In the hatchery hall among the typical odorogenous pollutants, there were determined 2 amines: 2-butanamine and 2-pentanamine, hydrogen sulfide, sulfur dioxide, carbon disulfide, sulfides and mercaptans. Ethyl mercaptan showed the highest levels as its mean concentration in the hatchery hall air exceeded 60 microg/m3 and in single samples even 800 microg/m3. A mean concentration of 2-butanamine and sulfur dioxide in the examined air also appeared to be relatively high--21.405 microg/m3 and 15.279 microg/m3, respectively. In each filter material, the air treatment process ran in a different mode. As the comparison reveals, the mean reduction of odorogenous contaminants recorded in the hall and subjected to biotreatment was satisfying as it surpassed 60% for most established pollutants. These high removal values were confirmed statistically only for single compounds. However, a low removal level was reported for hydrogen sulfide and sulfur dioxide. No reduction was recorded in the bentonite supplemented medium (BM) for sulfur dioxide and methyl mercaptan. In the organic medium (OM) no concentration fall was noted for dipropyl sulfide either. In all the media investigated, the highest removal rate (100%), not confirmed statistically, was observed for carbon disulfide. Very good results were obtained in the medium with a bentonite additive (BM) for both identified amines, whose mean elimination rate exceeded 60% (p