Table 3.

Biomarkers of internal exposure and of effect in workers exposed to fumes and aerosols of bitumen (n = 66, low n = 38, high n = 28) and in the reference group (n = 49)

VariableGroupPreshift
Postshift
During shift
Adjusted mean*Exposure effectPAdjusted mean*Exposure effectPShift effectP
1-OHP (ng/L)Reference178121611.210.20
Exposed2021.130.624442.050.0052.19<0.0001
Low1550.870.622961.370.261.900.0002
High2631.480.216663.080.00042.53<0.0001
1-OHP (ng/g crn)Reference148117911.210.11
Exposed1651.120.592961.660.021.79<0.0001
Low1450.980.942181.220.381.510.003
High1891.280.344022.250.0022.13<0.0001
Sum of five OHPHs (ng/L)Reference1,01511,15011.130.33
Exposed9970.980.912,3722.06<0.00012.38<0.0001
Low9330.920.651,6451.430.051.760.0002
High1,0641.050.823,4212.98<0.00013.22<0.0001
Sum of five OHPHs (ng/L)Reference894194511.060.47
Exposed8500.950.671,5561.65<0.00011.83<0.0001
Low8760.980.881,1901.260.081.360.0007
High8250.920.582,0342.15<0.00012.47<0.0001
8-OxodGuo/106 dGuoReference2.9913.5011.170.001
Exposed3.471.160.013.851.100.111.110.01
Low3.851.290.00024.091.170.021.060.24
High3.141.050.513.611.030.661.150.03
OTM (median)Reference1.2111.0510.870.13
Exposed1.831.52<0.00011.661.59<0.00010.910.23
Low1.721.420.0011.711.63<0.00011.000.98
High1.961.62<0.00011.611.540.00020.820.12
  • * Adjusted for age (<30, 30 to <50, ≥50 years), smoking, and German nationality.

  • Relative changes by exposure and during shift were expressed as factors for log-transformed variables.