[Effect of peat and certain farctions of peat on the respiratory processes in isolated skin].
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Baths↗
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[Spa treatment of degenerative spinal diseases with natural peat or the so-called peat paste].
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Age Factors↗
Copper and zinc adsorption onto poorly humified Sphagnum and Carex peat.
Peat generally has a high adsorption capacity and has been suggested as an adsorbent for metals in polluted waters. However, the adsorption potential of peat can be expected to be strongly dependent on the chemical properties of the water. In this study, the effect of pH, ionic strength (CaCl2 and NaCl concentrations), and metal concentration on Cu and Zn adsorption onto poorly humified Sphagnum and Carex peat was investigated in batch experiments using a fractional factorial experimental design. The pH value was varied between 4 and 8, the CaCl2 and NaCl concentrations between 1.2-6.2 and 0.4-43 mM, respectively, and the Cu and Zn concentrations between 0.05 and 0.5 mM. The amount of Zn adsorbed increased more with increasing pH than the amount of Cu adsorbed. The effect of NaCl/CaCl2 concentration was minor. It was found that Zn adsorption in particular, but also Cu adsorption, increased more with pH onto Carex peat than onto Sphagnum peat. In the pH interval 4-8, the removal of Zn from the solution increased from 0% to 80% using Carex peat and from 10% to 65% using Sphagnum peat as the adsorbent. The Carex peat sample decreased the Cu concentration by 80% at pH 4 and by 95% at pH 8 and for Sphagnum peat a decrease of 85% was maintained in the pH range investigated. The differences between Sphagnum and Carex peat were attributed to the habitat conditions at the time of peat formation. Carex peat has higher ash, nitrogen and sulphur concentrations, while Sphagnum peat contains a higher amount of uronic acid. In treating polluted waters with peat, a higher degree of metal removal can be expected at high pH values than at low. The removal of Cu, which has a high affinity to the peat surface, was less dependent on pH than Zn removal. Poorly humified Carex peat should be chosen in treating wastewaters high in pH.
Adsorption↗
An analytical protocol for the determination of total mercury concentrations in solid peat samples.
Traditional peat sample preparation methods such as drying at high temperatures and milling may be unsuitable for Hg concentration determination in peats due to the possible presence of volatile Hg species, which could be lost during drying. Here, the effects of sample preparation and natural variation on measured Hg concentrations are investigated. Slight increases in mercury concentrations were observed in samples dried at room temperature and at 30 degrees C (6.7 and 2.48 ng kg(-1) h(-1), respectively), and slight decreases were observed in samples dried at 60, 90 and 105 degrees C (2.36, 3.12 and 8.52 ng kg(-1) h(-1), respectively). Fertilising the peat slightly increased Hg loss (3.08 ng kg(-1) h(-1) in NPK-fertilised peat compared to 0.28 ng kg(-1) h(-1) in unfertilised peat, when averaged over all temperatures used). Homogenising samples by grinding in a machine also caused a loss of Hg. A comparison of two Hg profiles from an Arctic peat core, measured in frozen samples and in air-dried samples, revealed that no Hg losses occurred upon air-drying. A comparison of Hg concentrations in several plant species that make up peat, showed that some species (Pinus mugo, Sphagnum recurvum and Pseudevernia furfuracea) are particularly efficient Hg retainers. The disproportionally high Hg concentrations in these species can cause considerable variation in Hg concentrations within a peat slice. The variation of water content (1.6% throughout 17-cm core, 0.97% in a 10 x 10 cm slice), bulk density (40% throughout 17-cm core, 15.6% in a 10 x 10 cm slice) and Hg concentration (20% in a 10 x 10 cm slice) in ombrotrophic peat were quantified in order to determine their relative importance as sources of analytical error. Experiments were carried out to determine a suitable peat analysis program using the Leco AMA 254, capable of determining mercury concentrations in solid samples. Finally, an analytical protocol for the determination of Hg concentrations in solid peat samples is proposed. This method allows correction for variation in factors such as vegetation type, bulk density, water content and Hg concentration in individual peat slices. Several subsamples from each peat slice are air dried, combined and measured for Hg using the AMA254, using a program of 30 s (drying), 125 s (decomposition) and 45 s (waiting). Bulk density and water content measurements are performed on every slice using separate subsamples.
Environmental Monitoring↗
The effect of peat components on endocrine and immunological parameters and on trace elements--results of two pilot studies.
Peat and different peat preparations are successfully used in clinical therapies for different indications (as, for instance, in the field of gynecology). New studies show the biochemical effects of peat components which they have aside from their physical-thermal effects. This is of extraordinary interest with regard to the medical use of peat, because considerable concentrations of trace elements and heavy metals have been found in different kinds of peat. By means of atomic spectrometry it was investigated in 17 female patients with irritable bladder whether and how variations of the concentration of special trace elements and heavy metals (lead, cadmium, copper, manganese) could be measured within 24-hour urine after vaginal peat-mush treatments had been applied serially. Additionally, the effect of peat-mush baths compared to the effect of water baths (n=6) - both of which were applied to 17 female patients with degenerative diseases - was examined with regard to their special endocrinological parameters. The results concerning safety did not show any changes of the concentration of the trace-elements or heavy metals within the 24-hour urine. These results can be explained by the chelating features of the peat components, which are the reason for the absorption of the trace elements. Examinations done to compare the effects of peat-mush baths and water baths have shown that peat components - independent from their thermal effects - are the reason for the occurrence of special effects. This applies in particular to the parameter soluble interleukin-2-receptor. As regards estradiol, a significant increase could be measured after peat-mush baths had been applied to 17 postmenopausal female patients (n=11). Comparing these results with those of the group of patients treated with water baths, we noticed that the increase of estradiol was remarkably lower and not significant. The effect of the peat components is thought to be the reason for this.
Administration, Intravaginal↗
[The influence of the initial humidity of balneological peat on its pharmacological features].
The viscosity of balneological peat got special meaning according to its thermical features. Until now, there has been no answer on the question in how far balneological peat, which is prepared with different degrees of humidity, can vary the pharmacological character. Aim of this work was, on the one hand, to examine which initial degree of peat-humidity is necessary to get the wished viscosity in therapy when diluted with water. On the other hand, how far the pharmacological character of balneological is influenced by the initial degree of humidity. From peat, with initial different degrees of humidity, balneological peat is prepared, fulfilling the demands of the Quentin-Test and therefore the necessary consistence for therapy. Here in this work the in-vitro effect of aqueous peat extract (APE) on the spontaneous contractile activity of the smooth muscle fibres of guinea-pig stomachs was examined. The APE used got initial different degrees of humidity. It was found out, that the ability of peat according to a new water-uptake, with a initial humidity under 60%, was clearly reduced. Because of the reduced water content of balneological peat its thermical features were deteriorated. This goes for peat with a humidity factor < 60%. First, with the Quentin-Test, showing the optimal viscosity of peat before medical use, you can also make statements according its ability of maximum uptake of water, meaning the ability taking up water until it becomes gel-like. Second, the results show that the initial humidity of peat got no influence on the pharmacological features.
Animals↗
Variety in dustiness and hygiene quality of peat bedding.
Respiratory exposure to organic dust induces chronic pulmonary diseases both in farmers and horses. The aim of this study was to examine the variation of dustiness and hygiene quality of peat moss bedding. Materials studied were weakly decomposed sphagnum peat (A), weakly decomposed sphagnum peat warmed up in storage (> 30 degrees C) (B) and two more decomposed few-flowered sedge peats (C and D). The geometric mean of mesophilic fungi, thermotolerant fungi and thermophilic actinomycetes were determined from the material. Samples of inhalable dust and endotoxins were collected with IOM samplers and respirable dust with 10M foam samplers when the peat was rotated in a cylinder. The number of particles was detected with an optical particle counter. An LAL assay was used for analysing endotoxins from the filter samples. There were differences in the hygiene quality and dustiness between peat materials (p < 0.01). The geometric mean of fungi was smallest in material A. Warming-up increased the number of fungi in sphagnum peat, but on the other hand, it decreased the content of endotoxin (p < 0.01). Few-flowered peat materials contained thermophilic actinomycetes and material D also contained Aspergillus fumigatus. The concentrations of inhalable dust, respirable dust and the number of particles were smaller in the few-flowered peats (C-D) than in the sphagnum peats (A-B). It is concluded that there are differences in the dustiness and hygiene quality of peat bedding.
Air Microbiology↗
Evaluation of the permeation of peat substances through human skin in vitro.
Peat and various peat extracts have been successfully applied for a variety of clinical indications. Quite apart from the physico-thermal effects, new studies point towards the so-called "chemical effects" of peat containing substances. These effects include a stimulatory response of the spontaneous contractile activity (SCA) of smooth muscle (SM) tissue. The effects are, however, dependent on the possible permeability of pharmacologically active substances as naturally occurring ingredients of peat. Since peat is a mixture of various products it is necessary to examine the various peat types based upon their biological activity on SM tissue. In order to unequivocally prove the pharmacological activity of cutaneous peat treatment, in vitro permeation measurements of these actives across excised human skin can be used.HPLC analysis revealed that aqueous peat extracts contain up to 18 fractions of water-soluble compounds of fulvic and ulmic acids. These compounds have been found to have a stimulatory response on the contractile activity of SM tissue. In vitro diffusion studies showed that the permeability of these substances across human full thickness skin (thickness: 200 um(-1)) is highly selective and the resulting stimulatory activity is dependent on the permeated fraction. Especially, the HPLC fractions 7-11 and 14 are able to permeate human skin. Fractions 7-11 show a moderate stimulatory effect of SCA on SM for more than 90 min whereas fraction 14 shows the strongest stimulatory effect which was, however, suppressed after 87 min. These results show that the cutaneous therapy with peat treatment results in transcutaneaous permeation of biologically active fulvic and ulmic acid derivatives explaining the additional "chemical" effect of peat treatment in clinical practice.
Benzopyrans↗
Retention of nitrogen and phosphorous from liquid swine and poultry manures using highly characterized peats.
This paper reports on research designed to test the hypothesis that differences in peat composition will cause differences in amounts of N and P retained during contact with liquid swine manure (LSM) and liquid poultry manure (LPM). Peat types representing a wide range of properties were tested in order to establish which chemical and physical properties might be most indicative of their capacities to retain N and P from LSM and LPM. Eight-percent slurries (peat/LSM and peat/LPM) were measured for total nitrogen (TKN) and total phosphorous (TP) after 6, 24 and 96 hours. Tests were done to determine the TKN and TP contents of these peats, the LSM, and the LPM, both before and after they were mixed together. The N and P retention results revealed that most peats worked reasonably well at retaining N and P from either LSM or LPM. However, some peats were more effective than others. These peats also decreased the N and P levels in the liquid portion of the LSM. Peats with higher N retention capacities tended to have lower ash contents, but higher macroporosities and total cellulose contents. Peats with higher P retention capacities tended to have lower bulk densities, ash contents, total guaiacyl lignins contents, fulvic acids contents, but higher microporosities, macroporosities, H contents, and total cellulose contents. Peats with higher N and P retention capacities also had humic acid contents between 5-7%. The results of this study suggest that if these peats are used to reduce odors and N and P contamination, possible byproducts could be the production of odorless fertilizers.
Animals↗
Temperature and microbial activity effects on trace element leaching from metalliferous peats.
Due to geochemical processes, peat soils often have elevated concentrations of trace elements, which are gradually released following drainage for agriculture. Our objectives were to use incubation temperatures to vary microbial activity in two metalliferous peats (M7 acidic peat and M3 neutral peat) from the Elba, New York region, and to use periodic leaching to assess the extent of trace element release from these soils. Dried soils were mixed with glass beads to maintain aeration, moistened, and incubated at 4, 16, 28, and 37 degrees C in 10-cm-diameter x 8-cm-tall columns. Five incubation-leaching cycles were performed, each consisting of 7.3 d of incubation (28 d for the final cycle) followed by 16 h of leaching with synthetic acid rain at 2.5 mm h(-1). Microbial activity was determined initially and after the final leaching by measuring C mineralization following glucose stimulation. Cumulative respiration results were ranked 28 > 16 > 4 > 37 degrees C, with M7 acidic peat respiration values greater than M3 neutral peat at each temperature. Initial leachate pH levels were between 2 and 4, with acidification less pronounced and shorter-lived for the M3 peat. Leachate S, dissolved organic carbon (DOC), NO3-N, and trace elements declined with successive leachings (rebounding slightly in the final M3 leachate), with concentrations typically greater in the M7 leachate. Elemental losses followed the same general ranking (28 > 16 > 4 > 37 degrees C); losses at 28 degrees C were 15 to 22% for As, Cd, Ni, and Zn from the M7 peat; losses from M3 were comparable only for Cu (1%) and Ni (19%). The correlation of respiration with S, DOC, and trace elements losses indicates that microbial processes mediated the release of trace elements in both peat soils. Neutral M3 peat pH levels limited losses of most analytes.
Agriculture↗
Use of peat as a bedding material and dietary component for tom turkeys.
In a study of turkeys over the period 0 to 3 wk of age, body weights of birds fed 5 or 15% dietary peat or carrier-type feed byproducts (rice hulls, sunflower hulls, peanut hulls, soybean mill feed. wood flour, and corn cobs) were compared to those of turkeys fed a diet composed primarily of corn and soybean meal. Turkeys fed 15% dietary peat or carriers showed a greater growth depression than those fed the diluents at the 5% dietary level. At the 5% peat or carrier level, growth was not significantly (P greater than .05) depressed when birds were fed rice hulls (body weight was 98.5% of control), peat (97.1%), sunflower hulls (96.9%), and peanut hulls (95.8%); growth was significantly depressed (P less than .05) when birds were fed corn cobs (93.1%), soybean mill feed (92.9%), and wood flour (92.8%). Peat, when used as a drying agent for liquid agricultural byproducts, would account for 2 to 4% of the diet. Results of this study suggest that peat as a carrier fed at the 5% level would minimally affect growth. In a market study male turkeys were raised on floor pens containing peat or wood shavings and fed 0, 5, or 10% reed-sedge peat as a diluent of a typical corn-soybean meal mash diet. Body weights of turkeys fed 5 or 10% dietary peat showed a slight growth depression on both litter materials, compared with control. Higher body weights (nonsignificant) were observed for turkeys on wood shavings compared with those on peat litter after 12 wk of age.(ABSTRACT TRUNCATED AT 250 WORDS)
Animal Feed↗
HPLC determination of phenolic acids and antioxidant activity in concentrated peat extract--a natural immunomodulator.
The aim of this study was to devise a method for identification and quantification of phenolic acids in concentrated peat extract samples. The simple reversed-phase HPLC method for simultaneous determination of several phenolic acids was developed. The method was validated and it was suitable for the analysis of phenolic acids in peat extracts. This method allowed identifying eight phenolic acids in peat extracts. Phenolic profiles of two samples of peat extract obtained from different medicinal peats were similar, although variations in amounts of individual phenolic acids were observed. Also, slight variations in total phenolic content were detected. The antioxidant activity of peat extracts was evaluated with spectrophotometric ABTS assay. Differences in antioxidant activity were observed for two samples of peat extract produced from different peat varieties. This differences probably reflected phenolic composition of peat extracts.
Antioxidants↗
Poorly humified peat as an adsorbent for metals in wastewater.
Metal adsorption and surface charge determinations were performed previously on well-characterised Sphagnum and Carex peat samples. The aim of this investigation was to determine metal adsorption from complex wastewaters onto these peat samples and compare it to the adsorption onto peat granules, clinoptilolite, glauconite and a flue dust from steel production. A sulphide mine leachate, a landfill leachate and a laundry wastewater were chosen, giving a variation in pH, ionic strength, total organic carbon and concentrations of metals. Metal adsorption was determined in batch and column experiments. The wastewater composition was of great importance for metal removal efficiency, mainly due to the difference in dominating metal species. In the sulphide mine leachate, containing free metal ions, a high metal adsorption was observed onto both peat and inorganic adsorbents. In the landfill leachate the metals formed carbonate and organic complexes and a low metal removal was achieved. Contrary to the leachates, the laundry wastewater contained suspended particles. The high amount of metals removed, 80% of the Cu and 30-60% of the Zn concentration, was probably withdrawn bound to the particle fraction. The highest removal of metal ions was obtained in the sulphide mine leachate with Carex peat, removing 97-99% of the Zn and 85-100% of the Cu content. The Sphagnum peat sample removed 37-77% of the Zn and 80-100% of the Cu content. The differences found between Sphagnum and Carex peat were attributed to the original chemistry of the plant material and the habitat conditions at the time of peat formation. Generally, the combination of glauconite or clinoptilolite with the peat samples in column experiments gave a minor improvement in metal removal.
Adsorption↗
Predicting the release of metals from ombrotrophic peat due to drought-induced acidification.
Ombrotrophic peats in northern England and Scotland, close to industrial areas, have substantial contents of potentially toxic metals (Al, Ni, Cu, Zn, Cd and Pb) and of pollutant sulphur, all derived from atmospheric deposition. The peat sulphur, ordinarily in reduced form, may be converted to sulphuric acid under drought conditions, due to the entry of oxygen into the peats. The consequent lowering of soil solution pH is predicted to cause the release of metals held on ligand sites of the peat organic matter. The purpose of the present study was to explore, by simulation modelling, the extent of the metal response. Chemical variables (elemental composition, pH, metal contents) were measured for samples of ombrotrophic peats from three locations. Water extracts of the peats, and samples of local surface water, were also analysed, for pH, dissolved organic carbon (DOC) and metals. Metal release from peats due to acidification was demonstrated experimentally, and could be accounted for reasonably well using a speciation code (WHAM/Model VI). These data, together with information on metal and S deposition, and meteorology, were used to construct a simple description of peat hydrochemistry, based on WHAM/Model VI, that takes into account ion-binding by humic substances (assumed to be the "active" constituents of the peat with respect to ion-binding). The model was used to simulate steady state situations that approximated the observed soil pH, metal pools and dissolved metal concentrations. Then, drought conditions were imposed, to generate increased concentrations of H2SO4, in line with those observed during the drought of 1995. The model calculations suggest that the pH will decrease from the initial steady state value of 4.3 to 3.3-3.6 during rewetting periods following droughts, depending upon assumptions about the amount of potentially mobile soil S. The pH decreases will be accompanied by increases in concentrations of dissolved metals (Mg, Al, Ca, Ni, Cu, Zn, Cd, Pb) of an order of magnitude or more, depending upon assumptions about the replenishment of soil metal pools by deposition. In the most realistic scenario for present conditions, the severity of pH depressions will gradually decline due to the relatively slow depletion of the soil S pool by droughts. However, the magnitudes of heavy metal pulses will decline quite rapidly (over two or three droughts) because current and future metal deposition is unable to compensate for leaching losses from the soil pools.
Disasters↗
Atmospheric deposition of silver and thallium since 12 370 14C years BP recorded by a Swiss peat bog profile, and comparison with lead and cadmium.
A peat core from an ombrotrophic bog in Switzerland provides the first complete, long-term record (14 500 years) of atmospheric Ag and Tl deposition. The lack of enrichment of Ag and Tl in the basal peat layer shows that mineral dissolution in the underlying sediments has not contributed measurably to the Ag and Tl inventories in the peat column, and that Ag and Tl were supplied exclusively by atmospheric deposition. The temporal and spatial distribution of modern peaks in Ag and Tl concentrations are similar to those of Pb which is known to be immobile in peat profiles. Silver and Tl, therefore, are effectively immobile in the peat bog also, allowing an atmospheric deposition chronology to be reconstructed. Silver concentrations vary by up to 114x and Tl up to 241x. While Holocene climate change and land use history can explain the variation in metal concentrations and enrichment factors (EF) in ancient peats (i.e. pre-dating the Roman Period), anthropogenic sources have to be invoked to explain the very high EF values (up to 123 in the case of Ag and 12 in the case of Tl) in peat samples since the middle of the 19th Century. The "natural background" EF of Tl in ancient peats is remarkably close to unity, indicating a lack of significant enrichment of this element in atmospheric aerosols due to chemical weathering of crustal rocks. Silver, on the other hand, shows a pronounced enrichment from 8030 to 5230 (14)C years BP (12x compared to crustal rocks); this may be due to weathering phenomena or biological processes, both of which are driven by climate. Even compared to the natural enrichment of Ag during the mid-Holocene, however, the enrichments of Ag and Tl in modern peats from the Industrial Period are at least an order of magnitude greater. The Pb/Ag and Tl/Ag ratios show that Pb and Tl are preferentially released, compared to Ag, during smelting of argentiferous Pb ores mined during the Roman and Medieval Periods.
Air Pollutants↗
Seasonal variation in rates of methane production from peat of various botanical origins: effects of temperature and substrate quality.
The methane produced in peat soils can vary over the growing season due to variations in the supply of available substrate, the activity of the microbial community or changes in temperature. Our aim was to study how these factors regulate the methane production over the season from five different peat types of different botanical origin. Peat samples were collected on seven occasions between June and September. After each sampling, the peat soils were incubated at five different temperatures (7, 10, 15, 20 and 25 degrees C) without added substrate, or at 20 degrees C with added substrate (glucose, or H(2)/CO(2), or starch). Rates of methane production averaged over the season differed significantly (P<0.05, R(2)=0.76) among the five peat types, the minerotrophic lawn producing the highest rates, and the hummock peat producing the lowest. The seasonal average Q(10) values for each plant community varied between 4.6 and 9.2, the highest value being associated with the ombrotrophic lawn and the lowest value with the mud-bottom plant community. For the unamended peat samples, the rates of methane production from each plant community varied significantly (P<0.05) over the season. This implies that the quality of organic matter, in combination with changes in temperature, explains the seasonal variation in methane production. However, addition of saturating amounts of glucose, H(2)/CO(2) or starch at 20 degrees C significantly reduced the seasonal variation (P<0.05) in methane production in peat from the minerotrophic lawn, wet carpet and mud-bottom plant communities. This suggests that substrate supply (e.g. root exudates) for the micro-organisms also varied over the season at these sites. Seasonal variation in methane production rates was apparent in peat from the hummock and ombrotrophic lawn plant communities even after addition of substrates, suggesting that the active biomass of the anaerobic microbial populations at these sites was regulated by other factors than the ones studied.
Journal Article↗
Temperature-driven adaptation of the bacterial community in peat measured by using thymidine and leucine incorporation.
The temperature-driven adaptation of the bacterial community in peat was studied, by altering temperature to simulate self-heating and a subsequent return to mesophilic conditions. The technique used consisted of extracting the bacterial community from peat using homogenization-centrifugation and measuring the rates of thymidine (TdR) or leucine (Leu) incorporation by the extracted bacterial community at different temperatures. Increasing the peat incubation temperature from 25 degrees C to 35, 45, or 55 degrees C resulted in a selection of bacterial communities whose optimum temperatures for activity correlated to the peat incubation temperatures. Although TdR and Leu incorporations were significantly correlated, the Leu/TdR incorporation ratios were affected by temperature. Higher Leu/TdR incorporation ratios were found at higher temperatures of incubation of the extracted bacterial community. Higher Leu/TdR incorporation ratios were also found for bacteria in peat samples incubated at higher temperatures. The reappearance of the mesophilic community and disappearance of the thermophilic community when the incubation temperature of the peat was shifted down were monitored by measuring TdR incorporation at 55 degrees C (thermophilic activity) and 25 degrees C (mesophilic activity). Shifting the peat incubation temperature from 55 to 25 degrees C resulted in a recovery of the mesophilic activity, with a subsequent disappearance of the thermophilic activity. The availability of substrate for bacterial growth varied over time and among different peat samples. To avoid confounding effects of substrate availability, a temperature adaptation index was calculated. This index consisted of the log(10) ratio of TdR incorporation at 55 and 25 degrees C. The temperature index decreased linearly with time, indicating that no thermophilic activity would be detected by the TdR technique 1 month after the temperature downshift. There were no differences between the slopes of the temperature adaptation indices over time for peat samples incubated at 55 degrees C 3 or 11 days before incubation at 25 degrees C. Thus, different levels of bacterial activity did not affect the temperature-driven adaptation of the bacterial community.
Adaptation, Physiological↗
Exposure to peat dust: acute effects on lung function and content of bronchoalveolar lavage fluid.
Mechanised production of peat for fuel consumption is associated with high concentrations of organic dust, which is inhaled by the peat workers. In the present study 17 workers at two peat bogs in northern Sweden were examined. Personal sampling of total dust and the respirable fraction was performed during several workshifts. Dynamic spirometry was carried out before and at the end of shifts. Bronchoscopy with bronchoalveolar lavage (BAL) was performed in six subjects at the end of the working season and the results were compared with unexposed reference subjects. Peat workers using modern machines with ventilated cabins containing air filters were found to be exposed to low concentrations of peat dust. The recorded dust concentrations were below the threshold limit value for organic dust (5 mg/m3 air) in all but one worker. The respirable fraction of peat dust recorded in the breathing zone of the workers correlated significantly with a decrease in forced expiratory volume in one second (FEV1). The effect on lung function in non-asthmatic peat workers was, however, small. The concentration of lysozyme positive alveolar macrophages in BAL fluid was significantly lower in the peat workers compared with reference subjects. An inverse correlation was found between the mentioned cells and exposure to the respirable fraction of the peat dust. Furthermore, one particularly dust exposed worker had pronounced increases in alveolar macrophages, fibronectin concentration, and mast cells in BAL fluid.
Adolescent↗