Abstract:
The annual distribution, distribution by place of work and by occupational group of all the silicotic cases recorded at Gold Fields Ghana Limited (GGL) Hospital, Tarkwa from 1973 to 1996 were analysed. The trends of annual incidence rates of silicosis among GGL workers as a whole and separately among GGL underground workers and GGL surface workers were also analysed for the period. Data was obtained from GGL Hospital periodic reports and GGL Personnel Department records. Safety measures in place at the GGL mine against dust generation and inhalation were also observed and described. One hundred and sixty (160) cases of silicotic cases were recorded at the hospital during the study period. Of these, 133 (83.1%) were underground workers of GGL; 19 (11.9%) were surface workers of GGL and 8 (5%) were small-scale miners in the Tarkwa area. All the cases were males. The annual incidence rate of silicosis among GGL workers fell gradually from 6.1 cases per 1000 per year in 1993 to 0.4 cases per 1000 in 1993 and to 0 case per 1000 per year from 1994 to 1996. For the study period, the highest mean annual incidence rate of silicosis among GGL workers was observed among the mill crushers (13.4 cases /1000/year). The second and third highest rates were found among the drillers (11.1 cases/1000/year) and the blastmen (7.7 cases/1000/year) respectively. Considering the underground workers as one group and the surface workers as another group, it was observed that the mean annual incidence rate of silicosis among the underground workers of the mine was 5.3 times higher than among the surface workers (3.7 and 0.7 cases/1000/year respectively). However, when among the surface workers, one considers only the vulnerable occupational groups (exposed to large quantities of dust) of mill crushers and other mill workers, then the mean annual incidence rates are almost the same for both the underground and the vulnerable surface workers (3.7 and 3.6 cases/1000/year respectively). The safety measures in place at the GGL mine against dust generation and inhalation are good ventilation, exhaust ventilation systems, wet methods of drilling, water blasts to allay dust and use of respirators. Good supervision and continual education of workers about the hazards of mining are other ways of minimising the exposure of the workers to dust. It is recommended dust sampling should be re-introduced at the mine for protective and research purposes. Regular supply of appropriate respirators to workers as well as emphasis on the attention to the environmental working conditions of the drillers is also recommended.
