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The aim of this study was to establish whether the air-conditioning system in buses constitutes an additional source of indoor air contamination with fungi, and whether or not the fungi concentration depends on the period from the last disinfection of the system, combined with replacement of the cabin dust particle filter. The air samples to fungi analysis using impact method were taken in 30 buses (20 with an air-conditioning system, ACS; 10 with a ventilation system, VS) in two series: 1 and 22 weeks after cabin filter replacement and disinfection of the air-conditioning system. During one test in each bus were taken two samples: before the air-conditioning or ventilation system switched on and 6 min after operating of these systems. The atmospheric air was the external background (EB). After 1 week of use of the system, the fungi concentrations before starting of the ACS and VS system were 527.8 and 1053.0 cfu/m 3 , respectively, and after 22 weeks the concentrations were 351.9 and 1069.6 cfu/m 3 , respectively. While in the sample after 6 min of ACS and VS system operating, the fungi concentration after 1 week of use was 127.6 and 233.7 cfu/m 3 , respectively, and after 22 weeks it was 113.3 and 324.9 cfu/m 3 , respectively. Results do not provide strong evidence that air-conditioning system is an additional source of indoor air contamination with fungi. A longer operation of the system promoted increase of fungi concentration in air-conditioned buses only.

Introduction: The study aimed at determination of the usefulness of the subjective assessment of selected signs of fungi growth in flats and microclimate parameters to indicate the actual air contamination with culturable fungi, (1→3)-β-D-glucans and fungal spores., Material and Methods: This analysis covered 22 flats, the inhabitants of which declared in a questionnaire interview the presence of the developed mycelium on solid surfaces in the flat. Air samples for determination of the culturable fungi, (1→3)-β-D-glucans and (viable and non-viable) fungal spores concentrations indoor and outdoor the flats during the heating period were collected. During bioaerosol sampling microclimate parameters were measured. Predictive models for concentrations of the tested biological agents with regard to various ways to assess fungal contamination of air in a flat (on the basis of a questionnaire or a questionnaire and microclimate measurements) were built., Results: The arithmetic means of temperature, relative humidity, CO2 concentration and air flow velocity in the flats were respectively: 20.5°C, 53%, 1431.6 ppm and 0 m/s. The geometric mean concentrations of airborne fungi, (1→3)-β-D-glucans and fungal spores in these premises amounted to 2.9×102 cfu/m3, 1.6 ng/m3 and 5.7×103 spores/m3, respectively. The subjective assessment of fungi growth signs and microclimate characteristics were moderately useful for evaluation of the actual airborne fungi and (1→3)-β-D-glucan concentrations (maximum percent of explained variance (VE) = 61% and 67%, respectively), and less useful in evaluation of the actual fungal spore concentrations (VE < 29%). In the case of fungi, higher usefulness was indicated of the questionnaire evaluation supported by microclimate measurements (VE = 61.2%), as compared to the evaluation only by means of a questionnaire (VE = 46.9%)., Conclusions: Subjective evaluation of fungi growth signs in flats, separately or combined with microclimate measurements, appeared to be moderately useful for quantitative evaluation of the actual air contamination with fungi and their derivatives, but more extensive studies are needed to strengthen those findings., (This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.)

The aim of the paper was to discuss the problems related to the classification of B. subtilis and B. thuringiensis bacteria to the 2nd risk group under the 2005 decree of the Ministry of Health on hazardous biological agents (Law Gazette No. 81, item 716 with later amendments). The decree is a Polish implementation of the Directive 2000/54/EC generally consistent with its recommendations, but in the case of certain microorganisms a separate decision has been taken and having in mind the health of workers, changes in the list of hazardous agents existing in Poland have been made. The paper presents in detail the legal situation in this field, as well as current knowledge about the biology of these microorganisms, their use in the biotechnology industry and related production of allergenic proteins, and their effect on the human health. Placement ofB. subtilis and B. thuringiensis in the 2nd risk group resulted in the interpretative difficulties encountered by employers who use products containing these bacteria, institutions involved in such products trade and inspectorates supervising working conditions. Based on the literature review it is suggested to initiate actions leading to the development of hygiene norms for certain enzymes/bioinsecticides present in the air, the more that the tests to assess air concentrations of some of them are available. This solution would permit to remove B. subtilis and B. thuringiensis bacteria from the 2nd risk group without the risk for the care of workers' health.

Background: The aim of this study was to assess fungal air contamination in the processes associated with poultry breeding depending on the season. The evaluation was based on the determined concentrations of fungi and qualitative identification of isolated microorganisms., Materials and Methods: The study covered 2 hatcheries and 3 hen buildings. The air was sampled in spring, summer and autumn directly onto a filter using air aspirator. For the quantitative analysis of fungi, the medium MEA with chloramphenicol and streptomycin was used. The qualitative identification of fungi was carried out based on macro- and microscopic analysis., Results: The concentrations of total airborne mesophilic fungi in breeding facilities ranged from 1.22 x 10(3) to 5.87 x 10(5) cfu/m3 with the arithmetic mean value 1.60 x 10(5) cfu/m5. In 45% of the taken samples, these levels exceeded the reference value recommended in Poland for occupational environment exposure. The fungi concentration in the air of poultry houses was significantly modified by season (p = 0.04). A higher concentration of fungi occurred in autumn (p = 0.05). The dominant fungal microflora in the air was composed of molds (88%), with the most prevalent genus Acremonium. Yeasts constituted another 10% of bioaerosol and were mainly represented by genus Candida. The fungal aerosol contained two species qualified to the 2 group of risk--Aspergillus fumigatus and Candida tropicalis., Conclusions: Facilities of poultry farms are contaminated with high concentrations of fungal aerosols, especially in a colder season, often exceeding the recommended limits. Among the fungi, there are also present pathogenic microorganisms that may pose a risk to farm workers' health.

Background: In this paper the exposure assessment to airborne biohazards (organic dust, microorganisms, endotoxins and ((1 --> 3)-beta-D-glucans) as well as to ammonia and hydrogen sulfide among CAFO (swine farms) workers is presented., Materials and Methods: Occupational exposure assessment was carried out on 30 swine farms. Personal dosimetry was carried out among 90 swine farm workers to assess the exposure to organic dust, endotoxins and glucans. Concentrations of ammonia and hydrogen sulfide were measured using Draeger pipes. Endotoxins were assayed with the LAL test in a kinetic, chromogenic version and ((1 --> 3)-beta-D-glucans with the Glucatell test in a kinetic version., Results: Concentrations of inhalable dust ranged from 0.16 to 37.2 mg/m3, with AM = 3.65 mg/m3, whereas AM for respirable fraction was 0.39 mg/m3 with the range from zero to 4.28 mg/m3. Mean concentration of culturable bacteria was 4.79 x 10 (5) jtk/m3, and fungi concentration was ten times lower - 1.55 x 10(4) jtk/m3. Exposure to endotoxins with high degree of differentiation ranged from 95 to 147 885 EU/m3 in inhalable and from 5.5 to 18 708 EU/m3 in respirable fractions. Glucan concentrations ranged from 6 to > 5200 ng/m3 in unhalable and from 1 to 800 ng/m3 in respirable fraction. Ammonia concentrations in the workplace air ranged from 1.78 mg/m3 (2.50 ppm) to 30.1 mg/m3 (42.4 ppm). Hydrogen sulfide did not exceed the level of 4.1 mg/m3., Conclusion: Work conditions found in CAFOs may induce adverse effects on workers' respiratory system and should be considered as an important harmful agent. The protection of workers respiratory airways should be recommended.

Background: The aim of the study was to assess the occupational exposure to mesophilic microorganisms associated with commercial processing of compost for mushroom production., Materials and Methods: The air samples for microbiological analysis were collected directly on Petri dishes with Malt Extract Agar medium using Burkard Air Sampler. The quantitative and qualitative identification of mesophilic bacteria and mesophilic fungi were performed using the standard microbiological procedures., Results: Considerable variation in exposure to bioaerosols within the sectors of compost production were observed. The highest level of mesophilic bacteria in the air (4.17 x 10(4) cfu/m3) was measured during the mixing of raw materials with water and loading of the final compost piles to the pasteurization tunnels (3.54 x 10(4) cfu/m3). The highest concentration of mesophilic fungi was found in the air samples collected during the manual unrolling of straw (1.62 x 10(4) cfu/m3) and dosing of mycelium to the compost (1.15 x 10(4) cfu/m3). Among 33 identified bacteria and fungi species, Pasteurella sp, Proteus mirabilis, Streptomyces sp, Corynebacterium sp and Aspergillusfumigatus create the potential risk for health of exposed workers., Conclusions: The presence of microorganisms found in the air creats the potential risk for human health, therefore the use of personal equipment, protecting the respiratory tract and skin of exposed workers is strongly recommended.

Background: The quantitative assessment and qualitative identification of moulds at workplaces in wastewater treatment plants were the aim of the study., Materials and Methods: The study was carried out in four wastewater treatment plants, where 15 stationary points were selected according to mechanical, biological and sewage sludge treatment processes. In addition, background level samples from the city area were also collected. Bioaerosols were sampled with use of a Burkard Aerosol Sampler and directly put on Malt Extract Agar plates. Identification of moulds was based on morphological properties described in the professional literature., Results: The identified concentrations of moulds were low and ranged between 0.11 and 16.75 x 10(2) cfu/m3. The highest mean levels of fungal microflora were found during sewage sludge treatment processes. In total, there were 65 fungal isolates, of which 80% were found in wastewater treatment plants. In bioaerosol samples of the occupational origin, the highest (40%) amount of isolates originated from sewage sludge treatment processes and the lowest (25%) from biological treatment stages. In wastewater treatment plants, moulds of Aspergillus genus predominated and represented nearly 35% of all identified fungi. Comparing to background levels, the content of this genus was almost 4.5 times higher. Pathogenic Aspergillus fumigatus was found at all stages of wastewater treatment and Trichophyton genus at the stage of mechanical treatment. Moreover, there were numerous moulds of Mucor, Penicillium and Alternaria genera. In background samples moulds of Penicillium genus predominated and no pathogenic species were found., Conclusions: The obtained results reveal that the sewage sludge is the main source of mould emission into the air at workplaces in wastewater treatment plants. On account of the presence of moulds with the evidenced infectious and allergic activity it is suggested that personal protective equipment should be used by employees.

Mycotoxins are a quite numerous group of substances released as metabolites by molds, which badly affect human and animal health. Their impact on organisms resulting from alimentary exposure is well recognized, but the mechanisms by which they exert their health effects after inhalation exposure are still poorly investigated. The aim of this work was to review the literature concerning the outcomes of occupational exposure to mycotoxins present in the work environment. The author discusses the major mycotoxin classes, their chemical structure, some physicochemical properties and biological activity properties. This paper summarizes the results of investigations on the impact of occupational exposure to molds present in the workplace air in various branches of industry. Problems of identifying the mechanism of health effects exerted due inhalation exposure to mycotoxins are also discussed. This review shows that there is lack of good hygiene standards and legislation regulating the presence of these compounds in the workplace air. These is due to insufficient number of analyses aimed at estimating short-term inhalation exposure to mycotoxins and lack of monitoring of long-term exposure and its health effects. The authors concludes that occupational exposure to mycotoxins and their role in the development of pathological changes in the respiratory system require further investigations.

In metalworking, the temperature of the cutting edge can reach 700 degrees C, which can adversely affect either the surface of the metal processed or the cutting edge itself. To reduce the heat and friction, the metalworking fluids and coolants are used. The most common are the oil-in-water emulsions, which are a mixture of concentrated mineral oils, different additives, and water. The presence of water and organic substrates generates conditions for microbial growth. Bacterial endotoxins can also be frequently detected in metalworking fluids. Rapid rotation of the metalworking tools makes various biological agents to be released as droplet bioaerosols that can be inhaled by the workers, thus producing adverse health effects, mainly on the respiratory system. More than 130 species of bacteria (including pathogens), moulds and yeasts have so far been found in the metalworking fluids and coolants. This paper summarizes the outcomes of projects on the impact of biological agents present in metalworking fluids. Exposure to oil mist, bacteria and endotoxins as well as the variety of health effects resulting from that exposure have been discussed. The findings indicate that the most frequent symptoms reported by the workers include cough with phlegm, wheezing breath, chest tightness and throat irritation. The most common among the diagnosed diseases are chronic allergic bronchitis, asthma, hypersensitivity pneumonitis and acute respiratory dysfunction indicated by decreased FEV1 values. The main skin diseases include oil acne, bacterial infections, dermatomycosis and allergic reactions. The review made the authors conclude that the problem of occupational exposure to biological agents released with coolants during metalworking has not been well recognized in Poland.

Background: The purpose of the study was to evaluate exposure to biological and chemical agents in a sewage treatment plant., Materials and Methods: Sampling was carried out in the summer and wintertime at the morning workshift. Ninety-nine sewage workers taking part in the study were divided into four occupational subgroups: mechanical treatment, biological treatment, sewage sludge treatment, and operation control workers. Exposure to: H2S, SO2, Pb, Cd, Cr3+, Cr6+, endotoxins, (1 --> 3)-beta-D glucans, and microorganisms was evaluated with special identification of Gram-negative rods., Results: The concentrations of dust containing heavy metals and concentrations of gases from all stations did not exceed MAC values. Concentrations of endotoxins ranged from 0.08 to 223 ng/m3, and glucans from 0.00 to 163 ng/m3. The highest concentrations were found among sewage sludge treatment workers, in the summertime (geometric mean value = 37 ng/m3). In the winter, concentrations were almost ten times lower. Over sixty percent of all results exceeded the proposed reference value for airborne endotoxins (10 ng/m3). Concentrations of airborne bacteria in the sewage plant were at low level (10(2)( cfu/m3), except the sludge lagoon and sludge concentration building, where the results exceeded the proposed reference value for mesophilic bacteria (10(5) cfu/m3) "Environmental" bacteria (Pseudomonas, Burkholderia, Shewanella) predominated in the samples. There were also found enterobacteria genus (Enterococcus, family Enterobacteriaceae)--good indicators of hygienic cleanliness of the air., Conclusions: The study proved that the exposure varied and depended on the stage of sewage treatment. The sewage sludge treatment process was characterized by the highest emission of bioaerosols. All microorganisms found in the sewage plant belong to the second occupational risk group, under the ordinance of the Ministry of Health.