Asthma, allergies and respiratory symptoms in different activity groups of swimmers exercising in swimming halls.

BACKGROUND: Respiratory symptoms are common in competitive swimmers. However, among these and in swimmers at other activity levels the swimming distance, the total spent time in swimming halls and their medical background varies. Our objectives were, first, to assess their medical histories and the associations with respiratory symptoms among swimmers in different activity groups and then second, to study the pulmonary function findings and related medications in competitive swimmers who exercise in swimming hall environments the most. METHODS: First, 1118 participants consisting of 133 competitive-, 734 fitness- and 251 occasional swimmers answered questionnaires concerning their medical background, their respiratory symptoms in connection to swimming distance and their amount of time spent in swimming halls. Secondly, in 130 competitive swimmers, pulmonary function was tested by spirometry and a specific questionnaire was used to assess respiratory symptoms, medical histories and prescribed medication. RESULTS: Respiratory symptoms were reported by 18% of the studied swimmers. Competitive swimmers had significantly more symptoms than fitness- and occasional swimmers. Naturally competitive swimmers swum more than 2000 m and stayed by the pool more than 90 min, longer than the other activity groups of swimmers. Spirometry testing showed airway obstruction in 15 swimmers, which was 12% of the 130 competitive swimmers. 21 of them, had physician-diagnosed asthma and 16 of these individuals had prescribed medication for it. CONCLUSIONS: Competitive swimmers had the highest swimming hall exposure and reported significantly more respiratory symptoms. A high prevalence of airway obstruction findings in competitive swimmers with asthma and allergies suggests a need for future recommendations for regular testing and special medical care for competitive swimmers.

The suitability of the IOM foam sampler for bioaerosol sampling in Occupational Environments.

Concurrent samples were collected with Andersen and IOM foam samplers to determine whether if the IOM foam sampler can be applied to collect culturable microorganisms. Two different kinds of aerosols were studied: peat dust in a power plant and mist from coolant fluid aerosolized during grinding of blades and rollers in a paper mill. In the power plant, the concentrations of fungi were 2-3 times higher in the IOM samples than in the Andersen samples. However, more fungal genera were identified in the latter case. The methods yielded similar concentrations of bacteria and actinobacteria in the power plant. On the other hand, the performance of the IOM foam sampler was very poor in the paper mill, where stress-sensitive gram-negative bacteria dominated; low concentration of bacteria was detected in only one IOM sample even though the concentration of bacteria often exceeded even the upper detection limit in the Andersen impactor samples. It could be concluded that the IOM foam sampler performs quite well for collecting inhalable fungi and actinobacteria. However, the Andersen sampler provides better information on fungal genera and concentrations of gram-negative bacteria. Personal sampling with the IOM foam sampler provided an important benefit in the power plant, where the concentration ratio of personal to stationary samples was much higher for bacteria than for inhalable or respirable dust.

Respiratory and dermal exposure to organophosphorus flame retardants and tetrabromobisphenol A at five work environments.

Organophosphorus compounds (OPs) and tetrabromobisphenol A (TBBPA) are widely utilized as flame retardants (FRs) in plastics, textiles, rubbers, and building materials. Eight OPs and TBBPA were quantified by GC/MS from air samples collected from a furniture workshop, a circuit board factory, two electronics dismantling facilities, a computer classroom, and offices and social premises. In addition, dermal exposure was assessed with patch and hand wash samples at some workplaces. Triphenyl phosphate, tris(2-chloroethyl) phosphate, and tris(2-chloroisopropyl) phosphate were typical contaminants of the workplaces, whereas TBBPA, tricresyl phosphate, tri-n-butyl phosphate, and tris(2-ethylhexyl) phosphate were rather site-specific. The highest geometric mean of total FRs in the air samples was measured in personal samples atthe electronics dismantling facilities (2.9 and 3.8 microg/m3), whereas the stationary sample results from the other environments ranged between 90 and 720 ng/m3. Stationary samplings underestimated the personal exposure at three out of four work places where comparisons were made. Dermal exposure was shown for the first time at these occupational settings. The geometric mean of totalFR levels in patch samples ranged between 1.5 and 24 ng/cm2 and in hand wash samples between 3.5 and 34 microg/ two hands. The health effects of the measured FR levels remain unknown.

Laboratory and field testing of sampling methods for inhalable and respirable dust.

The performance of four sampling devices for inhalable dust and three devices for respirable dust was tested with different kinds of dusts in the laboratory and in the field. The IOM sampler was chosen as the reference method for inhalable dust, and the IOM sampler provided with the porous plastic foam media was used as the reference method for respirable dust. The other tested instruments were the Button sampler, the optical Grimm aerosol monitor, and the Dekati two-stage cascade impactor with cutoff sizes of 10 and 4 mu m. The study confirmed the applicability of the IOM and Button samplers. The new foam product followed the respirable criteria well. However, the foam sampler was unstable for measuring inhalable dust, probably due to its moisture absorption. In addition, high dust loads should be avoided with the foam sampler due to increase in filtering efficiency. The concentrations of inhalable dust measured with the Button sampler, the Grimm monitor, and the impactor sampler were usually close to those measured with the reference sampler. On the other hand, impactor sampling yielded higher respirable dust concentrations than the reference method in the field, which may have been caused by particle bounce; high dust loads should be avoided while using the impactor. The results also showed that the Grimm monitor enables real-time dust concentration determinations that are accurate enough for routine monitoring of occupational exposure and for testing efficiency of control measures in workplaces.

Controlling occupational allergies in the workplace.

OBJECTIVES: In recent years, the prevalence of work-related asthma has increased. Therefore, more attention needs to be paid to occupational allergens and their avoidance and control in workplaces. However, risk assessment of occupational allergen exposure is difficult because the relationship between exposure concentration, sensitization, and symptoms has not been fully established. This paper introduces a systematic and comprehensive approach to assessing and managing allergen risks at workplaces. MATERIALS AND METHODS: This approach relies on the cooperation and active communication during the whole process between management, employees, and health care personnel, with the assistance of experts when needed. In addition to gathering background information, including allergic symptoms, through questionnaires addressed to the management and employees, hazard identification is also processed in the workplace through observations and measurements. The methods generally recommended to reduce allergen exposure are compared with those used in the workplace. The process is to be carefully planned and documented to allow later follow-up and re-evaluation. RESULTS: The multi-faceted approach encompasses several risk assessment techniques, and reveals the prevalence of work-related allergic symptoms. The process effectively focuses on the potential means for controlling allergen exposure. CONCLUSION: Based on this approach, the synopsis on the critical points that require implementation of effective control measures can be presented.

Exposure to refractory ceramic fibres in the metal industry.

Refractory ceramic fibres (RCF) are used in thermal isolation in the metal industry where high temperatures are regularly employed. Asbestos materials were earlier commonly used for these purposes. In this work, two Finnish steel plants, three foundries and a repair shop were studied for the ceramic fibre exposure of their workers under normal production and during the replacement of oven insulation. Personal and stationary sampling was used together with a novel nasal lavage sampling for the evaluation of personal exposure. Fibres were counted with optical and electron microscopy and they were identified using an energy-dispersive X-ray analyser. Ceramic fibres were found in most production phases [range <0.01-0.29 fibres per cubic centimetre (f cm(-3))]. Considerably higher fibre counts were obtained during the maintenance work (range <0.01-14.2 f cm(-3)). Nasal sampling was found to correlate with the airborne fibre concentrations at the group level. The mean fibre concentrations varied from 34 to 6680 f ml(-1) of lavage liquid. Use of personal respiratory protectors diminished the exposure on the average as analysed in the lavage specimens, but the effect of respirator use did not appear clearly in the results. Because of the heat conditions, the workers used the respirators for a strict minimum period. A considerable exposure to RCF occurs in the studied plants. Its risk should be evaluated and managed more closely in view that the material is carcinogenic. Use of personal respiratory protectors should be encouraged. Their effective use could be verified by the nasal sampling for fibres after the work shift.

Effects of moisture damage and renovation on microbial conditions and pupils' health in two schools--a longitudinal analysis of five years.

Airborne microbes and pupils' symptoms were monitored in a moisture-damaged (index) school and a reference school for five consecutive years. These surveys were carried out in two separate years before the renovation of the index school, during the renovation, and one and two years after the renovation. Microbial concentrations were higher in the index school than those in the reference school before and during renovation, but afterwards, the levels decreased to the level of the reference school. The effect of remediation was seen as an altered mycobiota in the index school. Year-to-year variation of microbial concentrations, probably due to climatic factors, caused a peak in both schools but their difference remained. Several symptoms were more prevalent in the moisture-damaged school than in the reference school, but the differences disappeared during the renovations. These results emphasize the importance of using a reference building in assessing the microbial conditions of a moisture damaged building. Furthermore, microbial concentrations reflected well the technical condition of the construction, but the reported symptoms of the occupants did not strictly follow the timely fluctuation in microbial conditions.

Evaluation of the use of low flow passive sampling technique in offset printing plants.

OBJECTIVES: The aim of this study was to evaluate the suitability and applicability of low-flow passive tubes for sampling of organic solvents in occupational environment. MATERIALS AND METHODS: Laboratory and field studies were conducted to continue the evaluation of low-flow diffusive sampling combined with thermal desorption and gas chromatographic/mass spectrometric analysis in occupational hygiene surveys. Passive sampler tubes with Tenax GR adsorbent were employed to assess exposures to organic solvents in 10 small sheet-fed offset printing plants in Finland. The retention of the solvent compounds in the samplers was investigated using laboratory chamber studies. Active sampling with activated carbon tubes served as the control method. RESULTS: The laboratory tests showed that passive tubes had good retention, stability and reproducibility for the solvent compounds. Parallel passive and active sampling in both breathing zone and area monitoring in the printing plants yielded similar measurements though passive sampling tended to give slightly higher concentrations (by 5 to 12%). The suitability of passive sampling to be done by workers was also confirmed. The study also shows that exposure to organic solvents can be effectively reduced by the use of vegetable oil-based cleaning fluids. Especially, since ventilation and other protective measures are often inadequate in small facilities, the use of toxic cleaning solutions should be avoided. CONCLUSIONS: Passive sampling tubes with capillary orifice analyzed with thermal desorption GC-MS are well suited for measuring occupational solvent exposure. Method is well suited for sampling done by workers.

Microbial exposure, symptoms and inflammatory mediators in nasal lavage fluid of kitchen and clerical personnel in schools.

OBJECTIVES: The aim of this study was to investigate how the microbial conditions of kitchen facilities differ from those in other school facilities. The health status of the personnel was also studied. MATERIALS AND METHODS: The microbial investigations were conducted in six moisture-damaged schools and two reference schools. The symptoms of the kitchen personnel were surveyed with questionnaires and inflammatory responses in nasal lavage (NAL) fluid were measured. RESULTS: The total concentrations of airborne microbes were lower in kitchens than in other facilities of the schools. However, the occurrence of moisture damage increased the airborne microbial concentrations both in kitchens, and in other facilities. Bacterial concentrations were high on surfaces in the damaged kitchens. Gram-negative bacteria predominated, but also thermophilic bacteria and mycobacteria were detected. Respiratory and general symptoms were prevalent both among kitchen workers and clerical personnel in the moisture-damaged environments. Reported allergies and repeated respiratory infections were connected with high IL-4 concentrations in NAL fluid. Median concentrations of studied inflammatory mediators (NO, IL-4, IL-6 and TNF-alpha) were slightly higher in NAL samples of kitchen workers than among the clerical personnel. CONCLUSIONS: Kitchen facilites differ from other facilities of the school building for their moisture conditions and microbial contamination. Thus, they represent a specific type of environment that may affect the health status of the personnel.

Dermal exposure to polycyclic aromatic hydrocarbons among road pavers.

OBJECTIVES: Dermal exposure to polycyclic aromatic hydrocarbons (PAHs) and the role of an industrial by-product, coal fly ash, on workers' PAH exposure were investigated during stone mastic asphalt (SMA) paving and remixing. METHODS: PAH exposure was measured at eight sites during the laying of SMA containing coal fly ash or limestone (conventional SMA) as the filler. Six of the surveys were carried out during SMA paving and two during remixing of SMA (hot recycling at the paving site). Dermal PAH exposure was measured by hand washing (using sunflower oil and wiping with Kleenex tissues) before and after the work shift, and by placing exposure pads on the workers' wrists during the work shift. The analyses included 15 native PAHs from the hand-washing samples determined using high-performance liquid chromatography equipped with a two-channel fluorescence detector and 16 native PAHs and four methylated PAHs from the exposure pads using gas chromatography with mass-selective detection. RESULTS: The PAH results obtained using the pad and hand-washing methods (concentrations after the work shift) were equivalent and showed a strong correlation (r = 0.757, P < 0.001, N = 23 for total PAHs). There was a statistically significant difference between pre- and post-shift samples as measured by hand washing. The skin contamination by PAHs was significantly higher (P < 0.01) during remixing than during SMA paving. The variation in PAH contamination on the skin explained more of the variation in the excretion of urinary 1-hydroxypyrene and phenanthrols than the variation in the respiratory PAH concentrations. CONCLUSIONS: The industrial by-product investigated in asphalt, coal fly ash, had no statistically significant effect on the workers' dermal PAH exposure. The dermal exposure of paving workers to PAHs was higher during remixing than during SMA paving.

Potentially pathogenic, slow-growing mycobacteria released into workplace air during the remediation of buildings.

Construction workers' exposure to airborne viable mycobacteria was studied during the remediation of three moldy and two nonmoldy buildings. Furthermore, the concentrations of airborne fungal and actinobacterial spores were determined. The samples for the microbial analyses were collected using a six-stage impactor and an all-glass impinger sampler, and by filter sampling. Specific mycobacteria media and nonselective media were used for the cultures. The samples were cultured for the total numbers of rapidly growing and slow-growing mycobacteria, and the isolates obtained were identified to the genus or species level. Mycobacteria were recovered from the air during the remediation of two of the moldy buildings and one nondamaged building. Concentrations of mycobacteria up to 160 cfu/m3 were detected. A total of 43 mycobacterial isolates was recovered. Most of the isolates were slow-growers, only two rapid-growing strains being detected. The 38 identified isolates belonged to potentially pathogenic species, including Mycobacterium avium complex, M. scrofulaceum, and M. fortuitum, and to saprophytic species, including M. nonchromogenicum and M. terrae. Mycobacteria were the most often detected in samples taken with a six-stage impactor. They were found in buildings with both high and low concentrations of fungi. In conclusion, mycobacteria, both potentially pathogenic and saprophytic species, may be released into the indoor air during the remediation of buildings.

Evaluation of exposure to man-made vitreous fibers by nasal lavage.

The objectives of this study were to develop a biomonitoring method for the assessment of exposure to man-made vitreous fibers (MMVF), to examine the level of exposure to MMVF in the prefabricated house industry, and to study nasal inflammatory reactions and respiratory symptoms associated with MMVF among workers. Nasal lavage was performed on workers from two factories, and concentrations of MMVF were measured by electron microscopy. Cytokines (IL-6, IL-8, TNF-alpha, and IFN-gamma) were also assayed and inflammatory cells (lymphocytes, eosinophils, neutrophils, and macrophages) were counted microscopically. Concentrations of airborne fibers (longer than 5 microm) were measured for comparison. Moreover, the exposure to MMVF and the related symptoms were studied with a structured questionnaire. In nasal lavage samples, the mean concentration of MMVF (length >1.5 microm) was 3260 f/ mL in Factory 1, 1680 f/mL in Factory 2, and below 500 f/mL in the control group. About 52% of the retained fibers were longer than 100 microm. The group-specific mean concentrations of MMVF in nasal lavage samples correlated with production rates and airborne fiber levels in both plants. The airborne concentrations of MMVF both in the breathing zone and fixed-point samples were low (below 0.1 f/cm(3)). No significant differences in the biological response (inflammatory cells, cytokines) were found between the groups exposed and the control group. The workers complained of some irritation of the skin, eyes, and upper respiratory tract, which could be reduced by appropriate protective equipment. It is concluded that nasal lavage can be used as a biomonitoring method in the assessment of MMVF exposure.

Detection of mouse and rat urinary aeroallergens with an improved ELISA.

BACKGROUND: Risk analysis of laboratory animal work presupposes allergen monitoring with sensitive methods. Commercial ELISA kits have recently become available for the detection of mouse (Mus m 1) and rat (Rat n 1) urinary allergen from settled dust samples and air samples with high allergen levels. OBJECTIVE: Our aims were to enhance the sensitivities of the commercial ELISA kits for low aeroallergen levels (less than 1 ng/m(3)) and to test these methods with air samples collected from an animal facility. METHODS: Personal and stationary air samples were collected from an animal facility during various tasks of laboratory animal work and from various premises of the animal facility. RESULTS: The sensitivities of the ELISA assays were improved with a careful choice of analysis parameters and reagents. The detection limits of 0.1 ng/m(3) for Mus m 1 and 0.8 ng/m(3) for Rat n 1 were established. The sensitized assays enabled detection of mouse and rat aeroallergens also from premises in which animals or dirty cages were not present during sampling. CONCLUSION: These sensitive assays will help to perform risk assessment in laboratory animal work. However, there remains a lack of standardized analytic procedures and occupational exposure limits for laboratory animal allergens.

Laboratory and field testing of particle size-selective sampling methods for mineral dusts.

The performances of eight sampling devices were tested with mineral dusts in the laboratory and in a talc production plant. The IOM sampler was chosen as the reference method for inhalable dust, and the IOM samplers provided with the porous plastic foam media were used as the reference methods for both the thoracic and respirable aerosols. The other size-selective instruments tested included the Respicon virtual impactor, the optical GRIMM aerosol monitor, and a two-stage cascade impactor with cut points of 10 and 4 microm. The 37-mm cassettes were also included both as open- and closed-face versions. The study confirmed the usability of the IOM samplers for mineral dust, not only in its original version for the inhalable fraction but also its modified versions for the thoracic and respirable fractions. A high correlation with the two-stage impactor results is an indication of good reproducibility. The results increased the evidence that the 37-mm cassette is a poor indicator of inhalable aerosol. The concentrations obtained with both cassette methods were not only systematically too low but also showed large collection efficiency variability. Therefore, the results cannot be corrected by using correction factors. The concentrations of inhalable aerosol measured with the Respicon were generally low, but its performances for the thoracic and respirable fractions were closer to those for the reference samplers. The results also indicate that the GRIMM monitor is well-suited for such mineral dust determinations when very good accuracy is not required, but the immediate availability of the result is more important.

Firefighting efforts may lead to massive fungal growth and exposure within one week. A case report.

A case study on extensive fungal growth that occurred in an apartment building after firefighting efforts is described in this paper. Exposure to airborne microorganisms (both viable and total) was investigated by filter sampling in three periods before and during remedial actions after the fire. Material samples were also analyzed. Extensive mold growth was observed on the building materials as soon as eight days after the fire. High concentrations of fungal spores, 10(7) cfu/g, were found when material samples were analyzed. Concentrations of airborne fungal spores (10(4) spores/m3) were also high and increased by two orders of magnitude during the demolition of moldy building materials and during the clean-up after the demolition. The proportions of airborne viable fungi in comparison with the total spore concentrations were 28-83% immediately after the fire, but they had decreased to <1% two months after the fire during the reconstruction phase. Paecilomyces was the main fungal genus in the indoor air before and during the demolition, while Penicillium dominated during the reconstruction. Paecilomyces was not detected in the outdoor air. Paecilomyces and Penicillium were also found in the material samples. The results show that fast and extensive mold growth in a building may take place also in subarctic climates, at least during summer. High concentrations of fungal spores are released to the air during the demolition of moldy building materials and the following clean-up. Therefore, personal protection is necessary during such work.

Low-flow active and passive sampling of VOCs using thermal desorption tubes: theory and application at an offset printing facility.

While air sampling techniques using adsorbent-based collection, thermal desorption and chromatographic analysis have found a niche in ambient air sampling, occupational applications have been more limited. This paper evaluates the use of thermal desorption techniques for low flow active and passive sampling configurations which allow conveniently long duration sampling in occupational settings and other high concentration environments. The use of an orifice enables flows as low as 0.5 ml min(-1) and sampling periods up to several days without significant biases. A model is used to predict sampling rates of a passive sampler encompassing an orifice, a void space, glass wool, and the adsorbent. Laboratory and field tests conducted at a commercial offset printing facility, which contained a variety of volatile organic compounds (primarily aromatic but also a few chlorinated and terpene compounds at levels from 1 to 67,000 microg m(-3)), are used to evaluate the approach. Tenax GR and Carbosieve SIII, both singly and together, were employed as adsorbents. Side-by-side tests comparing high flow, low flow and passive samplers show excellent agreement and high linearity (r = 0.95) for concentrations spanning nearly five orders of magnitude. Active samplers were tested at flows as low as 0.5 ml min(-1), compared to typical flows up to 40 ml min(-1). Passive samplers demonstrated a linear range and agreement with predictions for adsorbate loadings from approximately 1 ng to nearly 10 microg. Using a chemical mass balance receptor model, concentrations in the facility were apportioned to solvents, inks and other indoor and outdoor sources. Overall, the use of low flow active and passive sampling approaches employing thermal desorption techniques provides good performance and tremendous flexibility that facilitates use in many applications, including workplace settings.

Diffusive uptake in passive and active adsorbent sampling using thermal desorption tubes.

Low flow active sampling techniques collecting vapors and gases using thermally desorbable adsorbents are now feasible and desirable in many applications as they permit long integration times, the potential for miniaturized sampling configurations, and other advantages. At very low air flow rates (< 1 ml min(-1)), diffusive uptake on adsorbents in conventional sorbent tubes may equal or exceed the active (pumped) uptake rate, and even at low flow rates (1-4 ml min(-1)), diffusive uptake may significantly bias measurements. Thus, corrections to account for the diffusive flux or means to limit the diffusive uptake are needed in low flow applications. This paper presents (1) a theoretical analysis of the role of diffusive and advective uptake for several sampling geometries of tube-type samplers; (2) experimental confirmation using both laboratory and field studies; (3) estimates of the tortuosity and porosity of the glass wool packing used to retain the adsorbent, parameters needed to estimate diffusive fluxes in passive and active sampling; (4) a demonstration that orifice-equipped low flow active samplers can reduce diffusive uptake and improve precision, and (5) a model predicting the saturated adsorbent layer that helps to account for the gradual decline in uptake rates seen in passive sampling. Diffusive uptake will depend on the tube configuration and diffusion coefficient of the substance of interest, but for conventional sampling tubes (0.4-0.5 cm id, 1.5 cm air gap), sample flow rates should be maintained above 1 to 4 ml min(-1) to keep errors below 5%. Laboratory experiments showed close agreement with theoretical calculations, and the field study using 1 to 4 d sampling periods and 0.3 ml min(-1) flows demonstrated that the orifice-equipped samplers essentially eliminated diffusive uptake. No significant practical difficulties are encountered using orifices, e.g., pressure drop is minimal. Experimental estimates of tortuosity (0.79 +/- 0.02) and porosity (0.92 +/- 0.10) of the glass wool packing (0.3 cm length) represent relatively little resistance to diffusion; however, variation in the packing and adsorbent placement can degrade the precision achievable by passive samplers. Diffusion barriers, consisting most simply of an orifice, may be used to lower the diffusive uptake. A needle-type orifice permits flows below 0.1 ml min(-1) and is suitable for sampling periods as long as several weeks, and it provided greater precision than conventional open-ended sampling tubes (8% compared to 13%). Finally, the gradual decrease in diffusive fluxes often seen in passive sampling is attributed to additional resistance posed by a saturated adsorbent layer, in agreement with a simple model based on total VOCs and specific adsorptivity of the adsorbent.