Exposure Period N Parameter Range Mean ± SD P-Value Normal range & unit of parameter
1-5 23 ESR 1-74.00 12.70 ± 16.85 0.058 0-7mm/hr (M), 0-10mm/hr (F)
6-10 14   2-22.00 8.64 ± 6.63 0.586  
11-15 128   1-100.00 10.86 ± 13.30 0.071  
16-20 56   2-38.00 10.77 ± 8.79 0.113  
21-25 61   2-53.00 10.54 ± 8.87 0.113  
26-35 21   2-62.00 12.71 ± 13.61 0.128  
CONTROL 30   1-36.00 6.60 ± 7.81    
Total 333   1-100.00 10.55 ± 11.57    
1-5 23 Hb 10-15.80 13.54 ± 1.60 0.149 13-18g/dl (M), 12-15g/dl (F)
6-10 14   11.6-14.60 13.52 ± 0.83 0.236  
11-15 128   7.6-16.80 13.09 ± 1.32 0.763  
16-20 56   10.6-16.70 13.07 ± 1.14 0.843  
21-25 61   10.6-16.40 13.14 ± 1.14 0.659  
26-35 21   11.9-21.10 13.61 ± 1.91 0.114  
CONTROL 30   9.1-14.90 13.01 ± 1.54    
Total 333   7.6-21.10 13.17 ± 1.33    
1-5 23 PCV 33-57.00 44.78 ± 5.72 0.073 40-50%(M), 36-47%(F)
6-10 14   38-48.00 44.36 ± 2.76 0.221  
11-15 128   25-58.00 43.05 ± 4.36 0.683  
16-20 56   35-55.00 43.04 ± 3.68 0.723  
21-25 61   35-54.00 43.28 ± 3.69 0.535  
26-35 21   39-49.00 43.38 ± 2.82 0.567  
CONTROL 30   30-49.00 42.70 ± 5.01    
Total 333   25-58.00 43.25 ± 4.17    
1-5 23 PLATELET ×109 153-430.00 250.13 ± 77.83 0.530 150-400 ×109 /L
6-10 14   108-320.00 217.93 ± 51.56 0.293  
11-15 128   75-423.00 239.71 ± 62.81 0.970  
16-20 56   115-420.00 224.57 ± 65.50 0.301  
21-25 61   114-370.00 225.92 ± 60.34 0.340  
26-35 21   133-318.00 217.86 ± 52.31 0.230  
CONTROL 30   141-382.00 239.23 ± 57.30    
Total 333   75-430.00 233.02 ± 62.62    
1-5 23 WBC  ×109 3.5-10.50 7.17 ± 1.43 0.916 4-11 ×109 /L
6-10 14   3.8-9.10 6.51 ± 1.60 0.680  
11-15 128   3.2-86.00 7.36 ± 9.89 1.000  
16-20 56   3.2-17.20 7.00 ± 2.51 .804  
21-25 61   3.2-15.70 6.84 ± 2.14 0.713  
26-35 21   3.6-10.40 6.47 ± 1.69 0.625  
CONTROL 30   4.9-11.00 7.36 ± 1.64    
Total 333   3.2-86.00 7.10 ± 6.32    
1-5 23 LYMPHOCYTE 33-63.00 53.96 ± 8.22* 0.000  
6-10 14   45-68.00 55.71 ± 6.24* 0.000  
11-15 128   30-72.00 52.59 ± 8.39* 0.000  
16-20 56   18-69.00 51.45 ± 11.21* 0.000  
21-25 61   27-75.00 52.18 ± 9.72* 0.000  
26-35 21   28-73.00 48.71 ± 9.37* 0.008  
CONTROL 30   25-57.00 41.60 ± 10.16    
Total 333   18-75.00 51.32 ± 9.81    
1-5 23 GRANULOCYTE 37-67.00 46.04 ± 8.22* 0.000  
6-10 14   32-55.00 44.29 ± 6.24* 0.000  
11-15 128   28-70.00 47.39 ± 8.36* 0.000  
16-20 56   31-82.00 48.55 ± 11.21* 0.000  
21-25 61   25-73.00 47.82 ± 9.72* 0.000  
26-35 21   27-72.00 51.29 ± 9.37* 0.008  
CONTROL 30   43-75.00 58.40 ± 10.16    
Total 333   25-82.00 48.68 ± 9.80    
Multiple Comparisons using Least Significant Difference (LSD) was the statistical method of analysis applied. *Indicates statistically significant difference.
Table 5: Value ranges and means of haematological parameters for the various exposure periods of the oil workers and the control subjects.