[Early change of pulmonary ventilation in new coal miners].
OBJECTIVE
To study the early effects of coal dust on lung function in new underground coal miners.


METHODS
Two 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.


RESULTS
The 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).


CONCLUSIONS
There 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.
Peng
Kai-Liang
KL
Department of Occupational Health and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province 430030, China.
Wang
Mei-Lin
ML
Du
Qing-Guo
QG
Li
Ya-Dong
YD
Attfield
Michael D
MD
Han
Gui-Hai
GH
Petsonk
Edward L
EL
Li
Shao-Kui
SK
Wu
Zhi-en
ZE
D000293:Adolescent; D000328:Adult; D003032:Coal Mining; D015331:Cohort Studies; D004391:Dust / Q000032:analysis; D005541:Forced Expiratory Volume; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects; D008297:Male; D016273:Occupational Exposure / Q000009:adverse effects*; D011446:Prospective Studies; D012123:Pulmonary Ventilation / Q000502:physiology*; D012907:Smoking / Q000503:physiopathology
D004391:Dust