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The immunological effects of environmental and/or occupational exposure to S02 in air as polluting gas have been examined in a group of 21 exposed men. The determination of S02 concentrations in ambient air in the work enviroment as well as in ambient air in residential areas of these men was performed, always using Amaya-Sugiura passive sampling and ion spectrophotometry. Mean concentration of S02 in ambient air in residential areas was 0.5792 mg • m-3 ± 0.2871 (0.22 to 1.52). Mean concentration of S02 in ambient air in the work enviroment was 2.2612 ± 2.1477 mg • m-3 (0.47 to 9.57). For the determination of T-cells and (CD19+)B-cell populations Behring monoclonal antibodies were used in indirect immunofluorescence tests. The serum levels of immunoglobulins: G, A, M, E; C3c and C4 complement components; total circulating immune complexes (CIC) as well as acute phase proteins: C-reactive protein (CRP), haptoglobin, ceruloplasmin and transferrin were determined by nephelometry. The mean number of total lymphocytes in men exposed to S02 was increased by 43% (p < 0.001). The stimulation T-cell line exposed to S02 was evidenced by increased number of (CD3+)T-cells, by about twice (p < 0.001) increased number of (CD4+)T-helper cells and by 68% (p < 0.001) increased number of (CD8+)T-suppressor cells. The higher increase of (CD4+)T-helper cells compared to (CD8+)T-suppressor cells caused the increased value of the (CD4+)T-helper/(CD8+)T-suppressor ratio by about 25% (p < 0.01) in the subjects exposed to S02. In contrast, a decreased number of (CD16+)NK cells by about 38% (p < 0.001) in men exposed to S02 was also observed. No changes were observed in the number of (CD19+)B-cells, as well as in the (CD3+)T/(CD8+)T-suppressor ratio. In the group exposed to S02, elevation of IgG serum levels by 23.3% (p < 0.001) was evidenced, as well as a decrease of C3c by 15.6% (p < 0.001) and C4 by 30% (p < 0.001), whereas total CIC in the serum was elevateds in same conditions by about 74% (p < 0.001). No changes were observed in the serum levels of IgA, IgM, IgE, CRP, haptoglobin, ceruloplasmin and transferrin. Significant positive correlations Irl (0.51 to 0.57) were only between S02 concentrations in air and serum concentrations of total CIC. Moreover, significant negative correlations Irl between S02 concentrations in air and leucocytes (WBC), and the determined T-cells populations and (CD19+)B-cells also were observed. In conclusion, environmental exposure to S02 can enhance proinflammatory processes in degree of exposure dependent manner and also can change some parameters of cell-mediated immunity.
Bitumens are produced and commonly used in paving, roofing and flooring operations, as well as corrosion-protective materials in Polish industry. During these processes bitumens, heated to the temperature range from 140°C to 200°C, emit multicomponent mixtures of toxic substances into the workplace air. Assessment of workers’ exposure to polycyclic aromatic hydrocarbons (PAHs) during road paving and production of roofing papers, asphalt-rubber blend and lute was the aim of this study. The results indicated that PAHs were detected in the breathing zone of all workers. Especially dangerous to human health was the process of roofing paper production. Exposure factors for PAHs (benzo [a] pyrene, benzo [a] anthracene, anthracene, dibenzo [a, h,] antracene, benzo [b] fluoranthene, benzo [k] fluoranthene, indeno [1,2,3-c, d] pyrene, chrysene, benzo [g, h, i] perylene) went up to 20.88 μg/m3.
The immunological effects of the environmental and/or occupational exposure to NO2 and NO in air as polluting gases have been examined in groups of 16 men. The determina-tion of NO2 and NO concentrations in ambient air in the work enviroment as well as in ambient air in residential areas of these men was performed, always by use of an Amaya-Sugiura passive sampling spectrophotometric method. Mean concentration of NO2 in ambient air in residential areas was 0.0210 mg x m-3 (0.0070 to 0.0470). NO2and NO mean concentrations in ambient air in the work enviroment were 0.0867 mg x m-3 (0.0165 to 0.1960) and 0.0614 mg x m-3 (0.0220 to 0.1090) respectively. For the determination of T-cell and (CD19+)B-cells populations Behring monoclonal antibodies were used in indirect immuno-fluores-cence tests. The serum levels of immunoglobulins: G, A, M, E; C3c and C4 complement components; total circulating immunological complexes (CIC) as well as acute phase proteins: C-reactive protein (CRP), haptoglobin, ceruloplasmin and transferrin were determined by nephelometry. Stimulation T-cell line in exposed to NO2 and NO was evidenced by in-creased number of (CD3+)T-cells, by about twice (p<0.001) increased number of (CD4+)T-helper cells and by increased number of (CD8+)T-suppressor cells. The higher increase in count of (CD4+)T-helper cells than (CD8+)T-suppressor cells population caused the increased value of the (CD+4)T-helper/(CD8+)T-suppressor ratio by about 25% (p<0.01) in the men exposed to NO2 and NO. No changes were observed in the number of (CD19+)B-cells as well as in the (CD3+)T/(CD8+)T-suppressor ratio. In men of exposed to NO2 and NO elevation of IgG serum concentration by a 17.7% (p<0.01) was evidenced as well as decreased of C3c by 18.6% (p<0.001) and C4 by 35% (p<0.001), whereas total CIC in serum was elevated by about twice (p<0.001). Significant positive correlations between concentrations of NO2 in air and numbers of total lymphocytes, (CD3+)-cells, (CD4+)T-helper, (CD8+)T-suppressor cells or IgG (/r/ from 0.31 to 0.71) as well as significant negative correlations between concentrations in air of NO2 and IgE, C3c, CRP or haptoglobin (/r/ from -0.49 to -0.31) were calculated. Moreover, significant positive correlation between NO concentrations in air in work place and counts of (CD3+)T-, (CD8+)T-suppressor, (CD19+)B-cells and levels in serum of C4, haptoglobin and ceruloplasmin (/r/ from 0.33 to 0.63) as well as significant negative correlations between NO concentrations in air in work place and serum levels of IgG, IgA and IgM (/r/ from -0.67 to -0.47) were also observed. In conclusion, environmental exposure to NO2 and NO can modificate in the peripheral blood of humans the parameters of cell-mediated and/or humoral immunity.
Knowledge of stable strontium did not advance significantly until extensive studies were undertaken on the effects of radioactive strontium. It is an element naturally occurring in the food chain and is applied in various areas of technology. However, diet and water are the main sources of human exposure to strontium. Consequently, the levels in drinking water and foodstuffs are of great interest from the toxicological and nutritional points of view. Worldwide, the strontium intake of adults varies between 0.1 and 4 mg/day which is normal and without any risk for the population. Occupational exposure to strontium or its compounds is rare and negligible. A review of worldwide alimentary strontium intake is given. In summa, strontium is a very inconspicuous element in scientific research, whether in toxicology, nutrition or environmental science.
Objective. The present study was carried out to investigate the effects of occupational lead exposure on the hematological and biochemical parameters in occupationally exposed and non exposed inhabitants of Karachi. Material and methods. In 100 lead exposed subjects recruited from automobile workshops, lead battery repair and recycling units located in Karachi and in 100 control subjects the general health status, hematological parameters and exposure markers for lead were measured. Results. Results indicated that the mean values of blood lead level and δ-aminolevulinic acid were significantly higher (P<0.05) while the activity of δ-aminolevulinic acid dehydratase were significantly decreased (P<0.05) among battery repair and recycling workers as compared to controls. The abnormalities in the blood lead level, δ-aminolevulinic acid and δ-aminolevulinic acid dehydratase were more frequent in lead exposed battery repair workers when compared with control subjects. The blood lead levels and δ-aminolevulinic acid were positively correlated while δ-aminolevulinic acid dehydratase was found to be negatively correlated with age, years of exposure and years of employment. Blood lead level was positively correlated with hemoglobin and RBC count while δ-aminolevulinic acid dehydratase was negatively correlated with hemoglobin concentration. The work related symptoms, droopiness, nasal symptoms and muscular pain were more frequent among battery repair workers as compared to control group. The findings of present study confirmed that occupational exposure to lead is associated with deviation in important hematological parameters and biological markers of exposure to lead among lead exposed workers, and also confirms the impact of lead exposure in the development of adverse effects among lead exposed workers. Conclusions. The study provides the data for risk assessment in lead battery repair workers of Karachi and suggests the need for preventive measures for battery repair workers and improvements to reduce occupational lead exposures to protect them from lead toxicity. It is suggested that hematological and physical examinations of lead exposed workers should be carried out periodically to prevent future health hazards.
A group of 150 persons living in the Lublin province of eastern Poland and occupationally exposed to tick bite were examined by the immunoenzymatic ELISA test for the presence of antibodies against tick-borne Spotted Fever Group (SFG) rickettsiae. The group consisted of 75 forestry workers employed in 3 forest inspectorates and 75 agricultural workers living in 2 villages. As a control group, 43 urban dwellers living in the city of Lublin and not occupationally exposed to tick bite were examined. Among 150 persons occupationally exposed to tick bite, the presence of antibodies against SFG rickettsiae was found in 54 (36.0% of the total). In the control group, the frequency of positive findings was only 4.7%, being significantly smaller compared to the exposed group (p=0.0001). Within the exposed group, the percentage of positive results in forestry workers (50.7%) was greater than in agricultural workers (21.3%); the difference was statistically significant (p=0.0002). Also within this group, the frequency of positive findings in males(46.5%) was significantly greater than in females (21.9%) (p=0.0029). In the exposed group, the positive results tended to increase with the age of the examined persons. However, a significant relationship between age and positive findings was found only in forestry workers (c2=14.207, p=0.00264), but not in agricultural workers and total exposed workers. The frequencies of positive results in forestry workers varied significantly depending on place of work (c2=11.271, p=0.00357). Similarly, the difference between the positive reactions in agricultural workers living in 2 villages proved to be significant (34.2% vs. 8.1%; p=0.0074). The obtained results indicate that people occupationally exposed to tick bite and living in the area of eastern Poland where over half of Dermacentor reticulatus ticks harbour SFG rickettsiae, are under significantly increased risk of infection with these rickettsiae.
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