OBJECTIVETo study the early effects of coal dust on lung function in new underground coal miners.

METHODSTwo hundred and eighty-seven male miners were selected from new employees at the Xuzhou Mining Group Company as study group, and 132 male students at a mining technical school were selected as control. Data collection included: individual demographic parameters, family medical history, occupational history, and smoking history, measurement of dust concentrations in work areas, and lung function tests. This prospective cohort study took place over 3 years during which time total dust and respirable dust concentrations in the new coal miners' work areas were measured twice each month. For both miner and student groups, FVC and FEV(1) were tested initially before dust exposure, and then 15 times over the 3 years.

RESULTSThe average total dust and respirable dust concentrations in the miners' work areas were 23.8 mg/m(3) and 8.9 mg/m(3) respectively, which greatly exceeded national health criteria. During the first year of dust exposure, the miners's average FVC was higher than that of the controls (5.19 L vs 4.92 L, P < 0.01). During the 2nd and 3rd year the difference in average FVC between miners and control group was not significant (5.14 L vs 5.12 L, P > 0.05). Before dust exposure, the miners' FEV(1) was significantly higher than that of the control group (4.48 L vs 4.28 L). In the miners group, FEV(1) declined rapidly during the first year following dust exposure (from 4.48 L to 4.25 L), and in the 2nd and the 3rd year the average FEV(1) of the miners was significantly lower than that of controls (4.34 L vs 4.56 L, P < 0.01), although there were some fluctuations during the follow-up period. Overall, the average FEV(1) of miners group showed a significant decline during the study. There were significant correlations between FVC or FEV(1) and age, height, weight, and smoking. The three-year total loss of FVC and FEV(1) in smoking miners (154 ml, 184 ml) were greater than in non-smoking miners (83 ml, 91 ml).

CONCLUSIONThere are apparent effects of coal dust on lung function in new underground coal miners, with FEV(1) being more impacted than FVC. Smoking may aggravate the effect of dust exposure on reducing lung function.

Adolescent ; Adult ; Coal Mining ; Cohort Studies ; Dust ; analysis ; Forced Expiratory Volume ; Humans ; Inhalation Exposure ; adverse effects ; Male ; Occupational Exposure ; adverse effects ; Prospective Studies ; Pulmonary Ventilation ; physiology ; Smoking ; physiopathology

OBJECTIVETo investigate whether inhalable particulate matters can cause the damage of chromosome or mitotic apparatus to produce micronucleus, and to evaluate genetic toxicology of moxa smoke on chromosome.

METHODSBy MTT method, the 24 h half maximal inhibitory concentration (IC50) of moxa smoke condensation (MSC) on Chinese hamster ovary (CHO) cells was 0.087 mg/mL. CHO cells, which were cultured in vitro, were divided into a solvent control group, a positive control group (cyclophosphamide as solvent), a low concentration group, a moderate concentration group and a high concentration group. The low concentration group, moderate concentration group and high concentration group were set approximately 1/8, 1/4, 1/2 of IC50, respectively. Whether micronucleus had dose-effect response induced by the damage of chromosome or mitotic apparatus was observed after CHO cells were contaminated by MSC in the low concentration group, moderate concentration group and high concentration group.

RESULTSThe rate of micronucleus induced by MSC in the low concentration group, moderate concentration group and high concentration group was higher than that in the solvent control group (all P < 0.05), which presented dosage-effect response. The experiment was repeated 3 times, indicating it was repeatable with statistical significance.

CONCLUSIONHigh concentration of MSC shows toxicity to induce chromosome damage, which disappears at low concentration. The genetic toxicology is also dependent on concentration, and the concentration of moxa smoke is essential. In clinical treatment, it is noted to control the level of moxa smoke, while the clinical safety standard of moxa smoke concentration is in need of further study.

Air Pollutants ; adverse effects ; Animals ; CHO Cells ; Cell Nucleus ; drug effects ; genetics ; Cricetinae ; Cricetulus ; Inhalation Exposure ; adverse effects ; analysis ; Micronucleus Tests ; Moxibustion ; adverse effects ; Particulate Matter ; adverse effects ; Smoke ; adverse effects ; analysis

Air Pollutants, Occupational ; adverse effects ; analysis ; Dust ; analysis ; Environmental Monitoring ; instrumentation ; methods ; Humans ; Industry ; Inhalation Exposure ; statistics & numerical data ; Maximum Allowable Concentration ; Occupational Exposure ; statistics & numerical data ; Quartz

OBJECTIVES: Nitrogen dioxide (NO2) has been inconsistently associated with gradual decreases in lung function. Here, we studied the effects of NO2 exposure in asthmatics by examining the association between changes in lung function and concentrations of NO2 which were personally measured. METHODS: Peak expiratory flow (PEF) and daily personal exposures to NO2 were recorded on 28 patients with asthma (confirmed by methacholine provocation test) over 4 weeks. We used generalized estimating equations to assess the relationship between personal NO2 exposure and PEF, adjusting for potential confounders such as age, gender, outdoor particulate matter, temperature, humidity, and exposure to environmental tobacco smoke. RESULTS: The personal NO2 exposures were higher than the corresponding ambient levels. The mean personal: ambient ratio for NO2 was 1.48. The personal NO2 exposures were not associated with the morning PEF, evening PEF, or the diurnal PEF variability. However, environmental tobacco smoke was negatively associated with both the morning and evening PEF. CONCLUSIONS: Among the asthmatic adults who participated in this study, we found no apparent impact of personal NO2 exposures on the peak expiratory flow.
Tobacco Smoke Pollution/adverse effects/analysis ; Time Factors ; Peak Expiratory Flow Rate/*drug effects ; Nitrogen Dioxide/*adverse effects ; Male ; Lung/*drug effects/physiology ; Korea/epidemiology ; Inhalation Exposure/*adverse effects/analysis ; Humans ; Female ; Asthma/epidemiology/*physiopathology ; Air Pollution, Indoor/adverse effects/analysis