Table 1
Sociodemographic characteristics of study participants (n = 112).
| Variable | Frequency | % |
|---|---|---|
| n | % | |
| Age in group (years) | ||
| 21–30 | 18 | 16.1 |
| 31–40 | 58 | 51.8 |
| 41–50 | 34 | 30.4 |
| 51–60 | 2 | 1.8 |
| Sex | ||
| Male | 107 | 95.5 |
| Female | 5 | 4.5 |
| Education Level | ||
| Primary Education | 27 | 24.1 |
| Secondary Education | 78 | 69.6 |
| Tertiary Education | 7 | 6.2 |
| Duration of Employment | ||
| 1–5 years | 78 | 69.6 |
| Above 5 years | 34 | 30.4 |
| Current smokers | 14 | 12.5 |
| Ever smokers | 6 | 5.4 |
| Ever worked in a dusty job before | 73 | 65.2 |
| Ever exposed to gas or chemical fumes in previous job | 4 | 3.6 |
Table 2
Personal respirable dust exposure levels among similar exposure groups—Underground.
| Similar Exposure Groups | Type of Activities | No. Samples | Mean Concentrations(mg/m3) | Range | ||
|---|---|---|---|---|---|---|
| AM(SD) | GM(GSD) | Median | ||||
| Truck Operators | Haulage | 19 | 0.38(0.24) | 0.29(0.37) | 0.45 | 0.08–0.80 |
| Jumbo/Long Hole Drill Operators | Drilling | 15 | 0.39(0.18) | 0.36(0.20) | 0.35 | 0.17–0.75 |
| Bogger Operators | Loading materials | 18 | 0.65(0.49) | 0.53(0.28) | 0.44 | 0.17–2.11 |
| Offsiders | Assisting Jumbo | 18 | 0.56(0.17) | 0.52(0.15) | 0.52 | 0.23–0.82 |
Table 3
Comparison of personal respirable dust exposure levels between similar exposure groups among underground gold miners.
| Similar Exposure Groups | No. Samples | GM(GSD) | Range | 95%CI of the difference | P-Value | |
|---|---|---|---|---|---|---|
| Truck Operators | 19 | 0.29(0.37) | 0.08–0.80 | Reference | ||
| Jumbo/Long Hole Drill Operators | 15 | 0.36(0.20) | 0.17–0.75 | –0.29–0.11 | 0.37 | |
| Bogger Operators | 18 | 0.53(0.28) | 0.17–2.11 | –0.47–0.04 | 0.019 | * |
| Offsiders | 18 | 0.52(0.15) | 0.23–0.82 | –0.45–0.07 | 0.009 | * |
Table 4
Personal respirable dust exposure levels among similar exposure groups—Open pit.
| Observational group | Type of Activities | No. Samples | Mean Concentrations(mg/m3) | Range | ||
|---|---|---|---|---|---|---|
| AM(SD) | GM(GSD) | Median | ||||
| Truck Operators | Haulage | 27 | 0.14(0.06) | 0.13(0.15) | 0.11 | 0.09–0.27 |
| Excavator Operators | Loading materials | 16 | 0.18(0.09) | 0.16(0.21) | 0.14 | 0.10–0.33 |
| Dozer Operators | Clearance and pushing materials | 18 | 0.17(0.08) | 0.16(0.18) | 0.16 | 0.10–0.32 |
| Quality Controller | Measuring depth of holes | 9 | 0.41(0.15) | 0.39(0.18) | 0.46 | 0.21–0.61 |
Table 5
Comparison of personal respirable dust exposure levels between similar exposure groups among open pit gold miners.
| Similar Exposure Groups | No. Samples | GM(GSD) | Range | 95%CI of the difference | P-Value | |
|---|---|---|---|---|---|---|
| Truck Operators | 27 | 0.13(0.15) | 0.09–0.27 | Reference | ||
| Excavator Operators | 16 | 0.16(0.21) | 0.10–0.33 | –0.20–0.45 | 0.21 | |
| Dozer Operators | 18 | 0.16(0.18) | 0.10–0.32 | –0.19–0.02 | 0.12 | |
| Quality Controller | 9 | 0.39(0.18) | 0.21–0.61 | –0.59–0.34 | p < 0.001 | * |
Figure 1
Prevalence of respiratory symptoms among Gold miners.
Table 6
Comparison of prevalence of respiratory symptoms between underground and open pit miners.
| Respiratory Symptom | Working Section | x2 | P value | ||
|---|---|---|---|---|---|
| Underground | Open pit | ||||
| Cough | 0.010 | 0.922 | |||
| Yes | 18(36.0) | 24(38.7) | |||
| No | 32(64.0) | 38(61.3) | |||
| Phlegm | 5.112 | 0.024 | * | ||
| Yes | 31(62.0) | 24(38.7) | |||
| No | 19(38.0) | 38(61.3) | |||
| Breathlessness | 0.127 | 0.721 | |||
| Yes | 20(40.0) | 28(45.2) | |||
| No | 30(60.0) | 34(54.8) | |||
| Wheezing | 2.316 | 0.128 | |||
| Yes | 13(26.0) | 8(12.9) | |||
| No | 37(74.0) | 54(87.1) | |||
| Chest tightness | 0.277 | 0.598 | |||
| Yes | 4(8.0) | 8(12.9) | |||
| No | 46(92.0) | 54(87.1) | |||
Table 7
Predictors of respiratory symptoms among gold cast miners.
| Respiratory Symptoms | β | SE | OR(95%CI) | P value |
|---|---|---|---|---|
| Cough | ||||
| Duration of Employment | 0.048 | 0.061 | 0.953(0.0846–1.073) | 0.425 |
| Cigarette smoking | –0.122 | 0.61 | 0.885(0.268–2.922) | 0.841 |
| Previous dust exposure | –0.009 | 0.46 | 0.991(0.402–2.441) | 0.984 |
| Age | –0.043 | 0.036 | 0.958(0.892–1.029) | 0.237 |
| Phlegm | ||||
| Duration of Exposure | –0.120 | 0.062 | 0.877(0.785–1.001) | 0.053 |
| Cigarette smoking | 0.554 | 0.611 | 1.740(0.525–5.766) | 0.365 |
| Previous dust exposure | 0.101 | 0.455 | 1.106(0.453–2.700) | 0.825 |
| Age | 0.056 | 0.036 | 1.057(0.986–1.134) | 0.119 |
| Breathlessness | ||||
| Duration of Exposure | –0.058 | 0.063 | 0.944(0.835–1.067) | 0.358 |
| Cigarette smoking | 1.849 | 0.700 | 6.353(1.611–25.052) | 0.008* |
| Previous dust exposure | –0.232 | 0.474 | 0.793(0.313–2.006) | 0.624 |
| Age | 0.048 | 0.037 | 1.049(0.977–1.128) | 0.189 |
| Wheezing | ||||
| Duration of Exposure | –0.115 | 0.090 | 0.891(0.747–1.063) | 0.199 |
| Cigarette smoking | 0.382 | 0.756 | 1.465(0.333–6.446) | 0.614 |
| Previous dust exposure | 1.469 | 0.816 | 4.343(0.878–21.447) | 0.072 |
| Age | 0.068 | 0.047 | 1.070(0.977–1.173) | 0.145 |
| Chest tightness | ||||
| Duration of Exposure | 0.123 | 0.092 | 1.135(0.947–1.360) | 0.171 |
| Cigarette smoking | 0.635 | 1.117 | 0.530(0.059–4.729) | 0.570 |
| Previous dust exposure | 1.440 | 0.913 | 4.222(0.705–25.280) | 0.115 |
| Age | 0.020 | 0.057 | 1.021(0.914–1.140) | 0.718 |
[i] ** Categorized as 1–5 years (short duration) and 6–15 years (long duration).
* Logistic regression, odds ratio, 95%CI, P-value < 0.005.
Figure 2
The prevalence of FEV1/FVC < 0.75.
Figure 3
The prevalence of FEV1/FVC < 0.7 and FVC < 80%.