Mechanical damage to rabbit tracheal epithelium from inhaling inert pyrite dust of needle-like structure. Part II.

The ultrastructure of rabbit tracheal epithelium was studied 2, 8 and 26 hours after termination of 8-hour inhalation of ground pyrite dust. Pyrite particles persist in the cytoplasm of ciliated cells throughout the interval followed up. Only through degeneration and elimination of these cells from the epithelium is the inhaled dust gradually removed from the mucous membrane. Goblet cells discharge pyrite-containing mucus into the ciliary border region for a period of 26 hours after cessation of inhalation thus inducing further damage to the ciliary border and the apical regions of the cells even after termination of inhalation. The morphological appearance of the ciliary border, especially in the first phase after termination of inhalation, suggests a disturbance of the self-cleaning function of the eipithelium of respiratory passages. The inhalation of aerosol of needle-like structure causes mechanical damage to tracheal epithelium. Substantial retardation of the onset of epithelial regeneration and slow rate of elimination of the inhaled aerosol from the tracheal mucosa was noted.     

Trichothecene mycotoxins in aerosolized conidia of Stachybotrys atra.

Stachybotrys atra is the etiologic agent of stachybotryotoxicosis, and this fungus and its trichothecene mycotoxins were recently implicated in an outbreak of unexplained illness in homes. S. atra was grown on sterile rice, autoclaved, dried, and then aerosolized by acoustic vibration. The distribution of particles (mass and number) was monitored on an aerodynamic particle sizer interfaced with a computer. Dust was collected on preweighed glass-fiber filters and extracted with 90% aqueous methanol. Extracts were tested for the ability to inhibit protein synthesis in rat alveolar macrophages, the ability to inhibit the proliferation of mouse thymocytes, and the presence of specific trichothecene mycotoxins. Virtually all of the particles were less than 15 micron in aerodynamic diameter, and the mass median diameter was 5 micron. Thus, most of the particles were respirable. Microscopic analysis of the generated dust revealed that ca. 85% of the dust particles were conidia of S. atra, another 6% were hyphal fragments, and the remainder of the particles were unidentifiable. Thus, greater than 90% of the particles were of fungal origin. The extracts strongly inhibited protein synthesis and thymocyte proliferation. Purified satratoxin H was also highly toxic in the same systems. Each of the individual filters contained satratoxin H (average, 9.5 ng/mg of dust). Satratoxin G and trichoverrols A and B were found in lesser amounts in some, but not all, of the filters. The limit of analysis is ca. 50 ng. These results establish that the conidia of S. atra contain trichothecene mycotoxins. In view of the potent toxicity of the trichothecenes, the inhalation of aerosols containing high concentrations of these conidia could be a potential hazard to health.     

An environmental nuisance: odor concentrated and transported by dust

Intensive swine production generates odorous emissions which flow from the buildings housing the animals. High ventilation rates bring in fresh air, remove heat and moisture and enhance pork productivity. Numerous compounds contribute to the uniquely offensive odors from swine facilities, including fatty acids, amines, aromatics and sulfur compounds. Dust particles, which originate predominantly from feces and feed, can adsorb and concentrate odorants in swine facilities. In addition, organic particles can decay and generate odorous compounds. Odorants can exist in much higher concentrations in the dust particles than in equivalent volumes of air. Thus, inhalation of odorous dust and deposition of the dust particles in the mucus overlying the olfactory mucosa are likely responsible for some odor-related complaints by swine farm neighbors. Accurate prediction of odor transport and dispersion downwind from swine farms may require models of dust dispersion and correlation between dust and odorant levels. Unfortunately, many approaches to estimating odor impact currently incorporate filtering of air to remove particulate matter before sensing by humans or electronic sensors. Accelerated progress in understanding this and other 'real world' odor control problems will require methodological innovations that allow quantification of odor in response to air streams containing vapor and particulate phases.     

Role of macrophage destruction products in the alveolar phagocytosis reaction]

Peritoneal macrophages (PM) of Wistar rats harvested after the intraperitoneal injection of paraffin oil were destroyed by repeated freezing-thawing. When injected intratracheally to control rats or to those after 4 daily exposured to TiO2 dust, these macrophage destruction products (MDP) caused a significant rise of both the alveolar macrophages (AM) and the neutrophilic leukocytes (NL) counts in the pulmonary washing-outs; the mean NL/AM ratio increased several times as compared to rats injected with normal saline intratracheally. Thus, the response to the inert dust particles plus the exogenous MDP became similar to the one observed after the cytotoxic (for instance silica) particles inhalation. Enhancing the NL contribution to the inhaled particles phagocytosis, the MDP led to a significant decrease of the mean "Dust load" of a single AM, although the total number of the engulfed particles increased. The predominant attraction of granulocytes and particularly of the NL as compared to the peritoneal macrophages was also found in the peritoneal exudates of rats injected with the MDP or silica suspension intraperitoneally, while the alveolar phagocytosis was not influenced. In vitro the MDP was shown to stimulate the NL migration and to facilitate the O2 consumption by PM. A possible role of the MDP as a multipotent controlling factor of phagocytosis response is briefly discussed.     

Biomonitoring of industrial dusts on animals. I. Bioaccumulation of dust components

The bioaccumulation of industrial dust components in laboratory animals exposed by inhalation was studied under environmental conditions. Three types of industrial emissions were investigated: magnesite emissions, wastes from nickel refinery and cement emissions, respectively. The findings revealed that the chemical components of the industrial dust particles inhaled by animals are accumulated not only in the lungs, but also in the other organs, bone and hair of the exposed animals. In addition, the dust components were found in the organs of the F1 generation as well. This suggests a new aspect for the assessment of the biohazard of industrial dust particles in the environment.     

Trichothecene mycotoxins in aerosolized conidia of Stachybotrys atra

Stachybotrys atra is the etiologic agent of stachybotryotoxicosis, and this fungus and its trichothecene mycotoxins were recently implicated in an outbreak of unexplained illness in homes. S. atra was grown on sterile rice, autoclaved, dried, and then aerosolized by acoustic vibration. The distribution of particles (mass and number) was monitored on an aerodynamic particle sizer interfaced with a computer. Dust was collected on preweighed glass-fiber filters and extracted with 90% aqueous methanol. Extracts were tested for the ability to inhibit protein synthesis in rat alveolar macrophages, the ability to inhibit the proliferation of mouse thymocytes, and the presence of specific trichothecene mycotoxins. Virtually all of the particles were less than 15 micron in aerodynamic diameter, and the mass median diameter was 5 micron. Thus, most of the particles were respirable. Microscopic analysis of the generated dust revealed that ca. 85% of the dust particles were conidia of S. atra, another 6% were hyphal fragments, and the remainder of the particles were unidentifiable. Thus, greater than 90% of the particles were of fungal origin. The extracts strongly inhibited protein synthesis and thymocyte proliferation. Purified satratoxin H was also highly toxic in the same systems. Each of the individual filters contained satratoxin H (average, 9.5 ng/mg of dust). Satratoxin G and trichoverrols A and B were found in lesser amounts in some, but not all, of the filters. The limit of analysis is ca. 50 ng. These results establish that the conidia of S. atra contain trichothecene mycotoxins. In view of the potent toxicity of the trichothecenes, the inhalation of aerosols containing high concentrations of these conidia could be a potential hazard to health.     

Anti-Inflammatory and Anti-Remodelling Potential of Ethanol Extract Rhodomyrtus Tomentosa in Combination of Asthma and Coal Dust Models

Background:Combination of asthma and coal dust is a chronic and recurring airway disease related to inflammation cell activation. The Rhodomyrtus tomentosa flowering plants native to South Kalimantan exhibit a broad therapeutic potential, like anti-inflammatory and anti-remodelling properties. This study aims to analyze the effect of ethanol extract of R. tomentosa leaves (EERTL) nebulizer on the number of inflammatory cells and histomorphometry of lung tissue in a mice-like model of a combination of asthma and coal dust.Methods:The 24 BALB/c mice were divided into four treatment groups (n= 6 per group), were sensitized with normal saline (K), OVA + coal dust (P1), OVA + coal dust + salbutamol (P2), and OVA + coal dust + EERTL (P3). Eosinophil cells, neutrophils, lymphocytes, epithelial thickness, smooth muscle, fibrosis subepithelial bronchioles, and the number of goblet cells as indicators of anti-inflammatory and anti-remodelling airways.Results:The number of eosinophils, neutrophils, and lymphocytes cells are given salbutamol or EERTL was significantly lower than the OVA-sensitized and coal dust exposure group only. There are meaningful differences in the average thickness of the epithelium, smooth muscle, and subepithelial fibrosis of bronchiolus. The histopathology picture of goblet cells showed an increase in the number and size (hyperplasia) in OVA-sensitized and coal dust exposure compared to another group.Conclusion:It was concluded that the EERTL nebulizer could reduce inflammatory cells and remodelling process from bronchoalveolar lavage in the mice combination of asthma and coal dust models.Key Words: Anti-Inflammatory, Anti-Remodelling, Asthma, Coal Dust, Rhodomyrtus tomentosa     

Microbial aerosols and actinomycetes in etiological considerations of mushroom workers' lungs.

Spent steamed compost, phase II compost, and dust emanating from spent compost during dumping of stationary-bed mushroom houses were examined bacteriologically. The total count for spent compost was 16 X 10(8) microorganisms per g. The total count for dust was 333 microorganisms per liter of air. Actinomycetes belonging to the genus Streptomyces often constituted 90% or more of isolates from dust, whereas mold spores constituted approximately 5%. Dust weight averaged 3.4 mg/liter of air and contained approximately 33% inanimate and 67% animate (microbial) particles. Spent compost and casing contained approximately 60% moisture; the average pH of compost was 6.93, and that of casing was 7.70. Ouchterlony precipitin results with antisera from workers afflicted with either farmer's or mushroom worker's lung were positive for Bacillus licheniformis, Micropolyspora faeni, Thermoactinomyces vulgaris, Aspergillus fumigatus, Humicola grisea var. thermoidea, spent compost, and phase II compost. Their usefulness in determining the etiology of this and related forms of allergic alveolitis is questioned and discussed. The relationship of dust particle size; microbial species, prevalence and antigenicity; and compost antigenicity to the etiology of mushroom worker's lung is discussed. The microbial ecology of mushroom compost and moldy hay associated with farmer's lung is compared.     

Antigen inhalation induces mast cells and eosinophils infiltration in the guinea pig esophageal epithelium involving histamine-mediated pathway

Antigen challenge in sensitized guinea pig esophagus in vitro induces mast cell degranulation and histamine release. This study tests the hypothesis that antigen inhalation in vivo induces infiltration of the esophageal epithelium by mast cells and eosinophils via a histamine pathway. Actively sensitized guinea pigs were exposed to inhaled 0.1% ovalbumin. One or 24 h after inhalation exposure, the esophagus was processed for immunofluorescent staining of mast cell tryptase and eosinophil major basic protein (MBP). Additional animals were pretreated with thioperamide, a histamine H4/H3 receptor antagonist. Total tryptase- and MBP-labeled cells and percent of positive cells in the epithelial layer were counted. The total number of mast cells was unchanged after inhalation challenge, but the percentage in the epithelium increased 1 h after challenge. The total number of eosinophils increased 1 h after challenge, and the percentage migrating to the epithelium increased by 24 h after challenge. Mast cell migration into the mucosal epithelium preceded that of eosinophils. Thioperamide inhibited mast cell and eosinophil migration. In conclusion, antigen inhalation in sensitized animals induces mast cells and eosinophils to infiltrate in the esophageal epithelium via histamine-mediated mechanism.     

Effect of ultrasonically nebulized distilled water on airway epithelial cell swelling in guinea pigs.

To investigate the pathogenesis of ultrasonically nebulized distilled water-induced airway narrowing, we studied the role of airway epithelial cells during a distilled water-inhalation challenge in an animal model of airway inflammation. Guinea pigs were divided into four groups: 1) a sham/saline (S/S) group: sham ozone followed by saline inhalation; 2) a sham/water (S/W) group: sham ozone followed by water inhalation; 3) an ozone/saline (O/S) group: ozone followed by saline inhalation; and 4) an ozone/water (O/W) group: ozone followed by water inhalation. After exposure to either 3.0 parts/million ozone or air at the same flow rate for 2 h, guinea pigs were anesthetized and tracheostomized, and then lung resistance (RL) was measured. For morphometric assessment, tissues were fixed with formaldehyde, stained with hematoxylin and eosin, and cut into transverse sections. Airway dimensions were either measured directly or calculated from the internal perimeter, the external perimeter, and airway wall area. There were no statistical differences in the values of RL before distilled water inhalation between the sham groups and the ozone groups. RL increased significantly after 10 min of distilled water inhalation in both the S/W group and the O/W group. In the S/W group, epithelial cells were swollen, and intercellular spaces were wider, resulting in significant increase in epithelial wall thickness, but there was no significant infiltration by inflammatory cells. In the O/S group, the epithelium showed infiltration by inflammatory cells without change in cell volume. In the O/W group, the epithelium showed both infiltration and a greater increase in epithelial wall thickness compared with the S/W group. These results suggest that airway epithelial cell swelling, induced by inhaled distilled water, increases with RL in guinea pigs and that this reaction may be accelerated by airway inflammation.     

Comparison of aerosol and bioaerosol collection on air filters

Air filters efficiency is usually determined by non-biological test aerosols, such as potassium chloride particles, Arizona dust or di-ethyl-hexyl-sebacate (DEHS) oily liquid. This research was undertaken to asses, if application of non-biological aerosols reflects air filters capacity to collect particles of biological origin. The collection efficiency for non-biological aerosol was tested with the PALAS set and ISO Fine Test Dust. Flow rate during the filtration process was 720 l/h, and particles size ranged 0.246–17.165 μm. The upstream and downstream concentration of the aerosol was measured with a laser particle counter PCS-2010. Tested bioaerosol contained 4 bacterial strains of different shape and size: Micrococcus luteus, Micrococcus varians, Pseudomonas putida and Bacillus subtilis. Number of the biological particles was estimated with a culture-based method. Results obtained with bioaerosol did not confirmed 100% filters efficiency noted for the mineral test dust of the same aerodynamic diameter. Maximum efficiency tested with bacterial cells was 99.8%. Additionally, cells reemission from filters into air was also studied. Bioaerosol contained 3 bacterial strains: Micrococcus varians, Pseudomonas putida and Bacillus subtilis. It was proved that the highest intensity of the reemission process was during the first 5 min. and reached maximum 0.63% of total number of bacteria retained in filters. Spherical cells adhered stronger to the filter fibres than cylindrical ones. It was concluded that non-biological aerosol containing particles of the same shape and surface characteristics (like DEHS spherical particles) can not give representative results for all particles present in the filtered air.     

盐城地区未成年过敏性疾病患者吸入性过敏原IgE检测结果分析

摘要 目的：通过研究分析盐城地区未成年过敏性疾病患者吸入性过敏原特异性IgE检测结果分布变化特点,为过敏性疾病预防和临床诊疗提供科学依据。方法：自2020年1月至2021年3月期间,选择430例未成年(<18岁)过敏性疾病患者,血清检测方法采用欧蒙公司生产的过敏原特异性IgE检测试剂盒。结果：430例患者中,血清过敏原IgE阳性166例(38.60%),其中尘螨和屋尘是主要的吸入性过敏原。血清IgE阳性率男性39%,女性36% (P>0.05),中学组女性阳性率（61.11 %）高于男性（45.83 %）（P<0.05）。不同年龄组间IgE阳性率有统计学差异（P<0.05）,蟑螂、尘螨、霉菌、豚草、屋尘和年龄组间有统计学差异（P<0.05）。不同临床症状与IgE阳性率有统计学差异(P<0.05),其中呼吸道过敏症状组IgE阳性率最高（48.30 %）,不同症状组间主要过敏原都是尘螨。屋尘阳性患者均合并尘螨阳性,其中70.93 %的患者表现出了呼吸道过敏症状。结论：尘螨、屋尘是盐城地区未成年过敏性疾病患者最主要的吸入性过敏原,研究血清过敏原分布,对未成年人过敏性疾病的预防、诊疗具有重要意义。     

The effect of asbestos cement, UICC asbestos samples and quartz on the peritoneum of the mouse.]

Aqueous suspensions of asbestos cement powder injected experimentally into the peritoneal cavity of mice act as a fibrogenic agent, as do chrysotile asbestos or chrysotile asbestos-containing soil samples. The fibrotic nodules caused by the dust resemble morphologically silicosis granulomas. In addition, asbestos cement has a characteristically strong cytotoxic effect during the first 2 weeks of the experiment. It is suggested that this is due to the chrysotile asbestos and/or the calcite component of the powder. Amosite and crocidolite, on the other hand, induce a diffuse peritoneal fibrosis with the appearance of numerous foreign body giant cells and asbestos bodies. Dust particles displaced to the regional lymph nodes are frequent in the animals treated with quartz, asbestos cement and asbestos-containing soil samples. A spindle cell type sarcoma arising from the visceral peritoneum is observed in animals injected with crocidolite or asbestos cement. In addition, dusts containing chrysotile asbestos induce considerable amyloidosis of the liver and spleen.     

Transport of microorganisms to Israel during Saharan dust events

Dust storms are serious meteorological events that affect the East Mediterranean region, primarily during the spring season. The physical and chemical nature of dust storms, their origin, and the meteorological conditions leading to the generation of storms have been fully documented, but knowledge on their biological content is almost nonexistent. Four dust events that occurred in the period 2004–2005 were sampled in Haifa, Israel, an urban area on the East Mediterranean coast, for biological characterization. Samples were taken before or after (depending on the meteorological conditions) as well as during the dust events. Dust particles were collected as two size fractions using a dichotomous sampler, and their elemental content was determined using X-ray fluorescence analyses. Airborne bacteria and fungi were collected with the Six Stage Andersen Viable Impactor. Fungi were identified by optical microscopy. Compared to adjacent clear days, there was an increase in the concentration of both atmospheric particles and elements of geological and marine origin during the dust events. The concentration of airborne microorganisms during the dust events was also higher, and the fungal population content was affected. On a winter clear day the abundant airborne fungi were Paecilomyces variotii, Penicillium glabrum, and Alternaria alternata. On a spring clear day, the persisting airborne fungi were Alternaria alternata, Geotrichum candidum, Penicillium chrysogenum, and P. glabrum. However, during two dust events the fungal population was dominated by Alternaria alternata, Aspergillus fumigatus, A. niger, A. thomii, Cladosporium cladosporioides, Penicillium chrysogenum, and P. griseoroseum. This study suggests that Saharan and other desert dust events in the East Mediterranean have a significant effect on the airborne microbial populations, which might impact on health, agriculture, and ecology.     

Ochratoxin A in airborne dust and fungal conidia

Farm workers are often exposed to high concentrations of airborne organic dust and fungal conidia, especially when working with plant materials. The purpose of this investigation was to study the possibility of exposure to the mycotoxin ochratoxin A (OTA) through inhalation of organic dust and conidia. Dust and aerosol samples were collected from three local cowsheds. Aerosol samples for determination of total conidia and dust concentrations were collected by stationary sampling on polycarbonate filters. Total dust was analysed by gravimetry, and conidia were counted using scanning electron microscopy. A method was developed for extraction and determination of OTA in small samples of settled dust. OTA was extracted with a mixture of methanol, chloroform, HCI, and water, purified on immunoaffinity column, and analysed by ion-pair HPLC with fluorescence detection. Recovery of OTA from spiked dust samples (0.9–1.0 μg/kg) was 74% (quantitation limit 0.150 μg/kg). OTA was found in 6 out of 14 settled dust samples (0.2–70 μg/kg). The total concentration of airborne conidia ranged from < 1.1 × 10⁴ to 3.9 × 15⁵ per m³, and the airborne dust concentration ranged from 0.08 to 0.21 mg/m³. Conidia collected from cultures of Penicillium verrucosum and Aspergillus ochraceus contained 0.4–0.7 and 0.02–0.06 pg OTA per conidium, respectively. Testing of conidial extracts from these fungi in a Bacillus subtilis bioassay indicated the presence of toxic compounds in addition to OTA. The results show that airborne dust and fungal conidia can be sources of OTA. Peak exposures to airborne OTA may be significant, e.g., in agricultural environments. This revised version was published online in August 2006 with corrections to the Cover Date.     

SLPI prevents cytokine release in mite protease-exposed conjunctival epithelial cells

House dust mites are a major source of allergens associated with allergic diseases including allergic conjunctivitis. Here, we demonstrate that mite-derived serine protease activity induces the release of cytokines from human ocular conjunctival epithelial cells in vitro and innate antiproteases, secretory leukocyte protease inhibitor (SLPI) and α1-antitrypsin, can inhibit the response. An extract prepared from a whole-mite culture induced the release of IL-6 and IL-8 and upregulated their gene expression in the human conjunctival epithelial cell line Chang, responses which were inhibited not only by a synthetic serine protease-specific inhibitor, AEBSF, but also by SLPI and α1-antitrypsin at a physiologically relevant concentration. The findings suggest a homeostatic role for SLPI and α1-antitrypsin against the proteases contained in allergen sources in the ocular conjunctiva and that exposure to house dust particles containing mite-derived serine protease activity could be involved in the initiation of sensitization through the ocular conjunctival epithelium and/or exacerbation of allergic conjunctivitis.     

Analysis of micronuclei, histopathological changes and cell proliferation in nasal epithelium cells of rats after exposure to formaldehyde by inhalation

The frequencies of micronuclei (MN), histopathological changes and cell proliferation were determined in the nasal epithelium of male Fischer-344 rats after exposure to formaldehyde (FA) by whole-body inhalation for four weeks (6h/day, 5 days/week). Groups of 12 rats each were exposed to the target concentrations of 0, 0.5, 1, 2, 6, 10 and 15ppm. The micronucleus test (MNT) was performed with nasal epithelial cells prepared from six animals per group. Two thousand cells per animal were analysed for the presence of MN. The other six rats per group were subcutaneously implanted with osmotic pumps containing 5-bromo-2'-deoxyuridine (BrdUrd), three days prior to necropsy. Paraffin sections were made from the nasal cavity (four levels) of these animals for histopathology and cell-proliferation measurements. The frequency of cells with MN was not increased in any of the groups. However, there was also no induction of MN in nasal cells of rats exposed to a single dose of cyclophosphamide (CP, 20mg/kg) by gavage and analysed 3, 7, 14 or 28 days after the treatment. In contrast, nasal epithelial cells from rats exposed to 10 or 15ppm FA vapour showed clear site-specific pathological changes (focal epithelial degeneration, inflammation and squamous metaplasia) in a decreasing gradient (anterior to posterior). Analysis of slides after anti-BrdUrd antibody staining clearly indicated increased cell proliferation (unit length labelling indices, ULLI) after exposure to 6ppm and higher. No treatment-related effects were measured after exposure to 0.5, 1 and 2ppm. When comparing the cell-proliferation rate of normal epithelium with that of directly adjacent metaplastic epithelium, no consistent pattern was found: depending on the location, cell proliferation of normal epithelia was either higher or lower. Our results support previous findings demonstrating local cytotoxic effects in the nose of rats after inhalation of FA. However, induction of MN in the nasal epithelium as an indicator of a mutagenic effect was not seen. Because only limited experience exists for the MNT with rat nasal epithelial cells, this result has to be interpreted with great care. The contribution of mutagenicity to FA's carcinogenicity in rat nasal epithelium remains unclear.     

Bronchial hyperreactivity is associated with enhanced grain dust-induced airflow obstruction.

Bronchial hyperreactivity (BHR) is associated with the presence of airway inflammation in asthma and is seen in individuals occupationally exposed to grain dust. To better understand the relationship between BHR and pulmonary inflammation after grain dust exposure, we carried out an inhalation challenge to corn dust extract (CDE) on seven subjects with BHR [a 20% or greater decrease in forced expiratory volume in 1 s (FEV(1)) compared with diluent FEV(1) with a cumulative dose of histamine 相似文献   

In vitro exposure of nasal epithelial cells to atmospheric dust

Dust storms are common phenomena in many parts of the world, and significantly increase the level of atmospheric particulate matter (PM). The soil-derived dust is a mixture of organic and inorganic particles and even remnants of pesticides from agricultural areas nearby. The risk of human exposure to atmospheric dust is well documented, but very little is known on the impact of inhaled PM on the biological lining of the nasal cavity, which is the natural filter between the external environment and the respiratory tract. We developed a new system and methodology for in vitro exposure of cultured nasal epithelial cells (NEC) to atmospheric soil-dust pollutants under realistic and controlled laboratory simulations that mimic nasal breathing. We exposed cultured NEC to clean and dust-polluted airflows that mimic physiological conditions. The results revealed that the secretion of mucin and IL-8 from the NEC exposed to clean and dust-polluted airflows was less than the secretion at static conditions under clean air. The secretion of IL-8 from NEC exposed to dust-polluted air was larger than that of clean air, but not larger than in the static case. The experiments with dust air pollution that also contained agricultural pesticides did not reveal differences in the secretion of mucin and IL-8 as compared to the same pollution without pesticides.     

城市绿化树种的滞尘效应——以哈尔滨市为例

提出以植物材料的滞尘功能作为城市绿地设计中重要依据 ,对哈尔滨市 2 8个树种进行滞尘测定和叶表电镜扫描 ,结果表明 ,不同的树种滞尘量差异显著 ,树种之间的滞尘能力可相差 2～ 3倍以上 .常绿针叶树种中 ,红皮云杉、杜松是优良的滞尘树种 ,4周后滞尘分别达到 5 .7和 4.4g·m-2 .落叶阔叶树种中 ,银中杨、金银忍冬、山桃稠李是优良的阔叶滞尘树种 ,两周后滞尘分别达到 1.9、2 .0和 2 .45 g·m-2 .电镜观察发现 ,叶表皮具沟状组织、密集纤毛的树种滞尘能力强 ,叶表皮具瘤状或疣状突起的树种滞尘能力差 ,并结合滞尘测定对滞尘方式进行了讨论 .