Abstract:

Studies on the health effects of occupational exposure to dust on the respiratory function of the gold miners in Orkney gold minefields in South Africa are reportedly scarce.

This study was aimed at revealing the physiological effect(s) of exposure to dust, in the underground mine on respiratory functions such as the forced vital capacity (FVC), the forced expiratory volume in one second (FEV1), and the peak expiratory flow (PEF); and compare this with non-miners.

A case-control study was conducted with the participants matched as close as possible. The gold miners were the case while the non-miners were the control.

The major instrument that was used to assess the respiratory function was the CONTEC SP10 digital spirometer. For the secondary effects, sphygmomanometer, digital weight scale, digital heart rate monitor were used.

Data Analysis was carried out using the Statistical Package for Social Sciences (SPSS) version 20 and the paired sample t-test.

There were statistically significant differences in all the 3 respiratory functions assessed between the gold miners and non-miners. The forced expiratory volume for the gold miners and non-gold miner are weakly and positively correlated (r = 0.289, p < 0.000). There was a significant mean difference between the FVC for gold miners and non-gold miners in Orkney (t221 = 8.135, p < 0.000) .Urgent steps at reducing the amount of occupational exposure to dust with possible resultant silicosis are needed to curb these observed variations.

Keywords: Dust exposure, respiratory functions, silicosis, underground mine workers.

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