Table 2

Prevalence of respiratory symptoms and lung function parameters by survey, exposure status and job tasks

First survey (2012)Second survey (2014)
Exposed (n=588)Unexposed (n=497)
p Value
Exposed (n=205)Unexposed (n=177)
p Value
Respiratory symptomsnPer centnPer centnPer centnPer cent
Chronic cough366.0122.40<0.05**2612.6073.90<0.05**
Chronic phlegm91.541.000.28125.8042.200.07
Shortness of breath355.871.40<0.05***5828.202212.20<0.05**
Exposed applicators (n=103)†Unexposed (n=102)†
Lung function (male)MeanSDMeanSDMeanSDMeanSDp Value
FVC (L)4.250.634.310.590.47
FEV1 (L)3.510.563.670.50<0.05*
FEF 25%–75% (L/s)3.941.264.521.17<0.05***
nPer centnPer cent
FEV1/FVC <0.83830.1698.04<0.05***
Lung function (female)Exposed re-entry workers (n=56)Unexposed (n=55)p Value
FVC (L)3.150.493.270.430.22
FEV1 (L)2.630.452.790.37<0.05*
FEF 25%–75% (L/s)3.060.893.560.89<0.05**
nPer centnPer cent
  • *p<0.05, **p<0.01, ***p<0.001.

  • †Fewer individuals entered in the lung function analyses than for respiratory symptoms in stage 2 due to stringent quality control of the spirometric data.

  • FEF, forced expiratory flow.