Table 3

Correlation coefficients between concentrations of mercury in tissues, age and number of amalgam surfaces. a


I-Hg in blood
 MeHg in blood
 I-Hg in occipital cortex
 MeHg in occipital cortex
 Hg in occipital cortex
 Hg in pituitary
 Hg in thyroid
 Hg in toenail
 Hg in abdominal muscle
 Age
 Filled surfaces – amalgam
I-Hg in blood
 Correlation
0.251
 -0.026
 0.052
 0.006
 -0.062
 -0.039
 0.065
 -0.045
 -0.402
 0.432

Sig. (2-tailed)
0.181
 0.891
 0.784
 0.974
 0.744
 0.845
 0.738
 0.815
 0.028
 0.017

N
30
 30
 30
 30
 30
 28
 29
 30
 30
 30
MeHg in blood
 Correlation
 0.246
-0.071
 0.725
 0.232
 -0.107
 -0.090
 0.634
 0.230
 0.055
 -0.126

Sig. (2-tailed)
 0.198
0.710
 <0.001
 0.218
 0.572
 0.648
 <0.001
 0.221
 0.774
 0.507

N
 29
30
 30
 30
 30
 28
 29
 30
 30
 30
I-Hg in occipital cortex
 Correlation
 0.253
 0.134
0.339
 0.927
 0.967
 0.993
 -0.086
 -0.155
 0.334
 0.081

Sig. (2-tailed)
 0.186
 0.490
0.067
 <0.001
 <0.001
 <0.001
 0.656
 0.414
 0.071
 0.669

N
 29
 29
30
 30
 30
 28
 29
 30
 30
 30
MeHg in occipital cortex
 Correlation
 0.079
 0.804
 0.081
0.617
 0.287
 0.336
 0.586
 0.258
 0.154
 -0.136

Sig. (2-tailed)
 0.686
 <0.001
 0.677
<0.001
 0.124
 0.081
 0.001
 0.169
 0.416
 0.472

N
 29
 29
 29
30
 30
 28
 29
 30
 30
 30
Hg in
 Correlation
 0.147
 0.713
 0.604
 0.768
0.904
 0.910
 0.154
 -0.048
 0.295
 0.080
occipital cortex
 Sig. (2-tailed)
 0.447
 <0.001
 0.001
 <0.001
<0.001
 <0.001
 0.425
 0.800
 0.113
 0.676

N
 29
 29
 29
 29
30
 28
 29
 30
 30
 30
Hg in pituitary
 Correlation
 -0.002
 -0.062
 0.652
 -0.086
 0.390
0.953
 -0.100
 -0.149
 0.261
 0.173

Sig. (2-tailed)
 0.993
 0.748
 <0.001
 0.659
 0.036
<0.001
 0.607
 0.432
 0.163
 0.360

N
 29
 29
 29
 29
 29
28
 29
 30
 30
 30
Hg in thyroid
 Correlation
 0.352
 0.142
 0.602
 0.105
 0.396
 0.402
-0.087
 -0.125
 0.351
 0.031

Sig. (2-tailed)
 0.072
 0.479
 0.001
 0.603
 0.041
 0.038
0.667
 0.525
 0.067
 0.875

N
 27
 27
 27
 27
 27
 27
27
 28
 28
 28
Hg in toenail
 Correlation
 0.060
 0.631
 -0.093
 0.649
 0.525
 -0.095
 -0.091
0.139
 0.158
 -0.328

Sig. (2-tailed)
 0.760
 <0.001
 0.638
 <0.001
 0.004
 0.629
 0.660
0.472
 0.414
 0.083

N
 28
 28
 28
 28
 28
 28
 26
29
 29
 29
Hg in abdominal muscle
 Correlation
 -0.055
 0.220
 -0.079
 0.328
 0.186
 -0.038
 0.335
 0.130
-0.003
 -0.081

Sig. (2-tailed)
 0.778
 0.251
 0.683
 0.083
 0.334
 0.847
 0.088
 0.510
0.988
 0.672

N
 29
 29
 29
 29
 29
 29
 27
 28
30
 30
Age
 Correlation
 -0.408
 0.096
 -0.208
 0.037
 -0.084
 -0.287
 -0.215
 0.200
 0.055
-0.610

Sig. (2-tailed)
 0.028
 0.621
 0.278
 0.849
 0.664
 0.131
 0.282
 0.308
 0.778
<0.001

N
 29
 29
 29
 29
 29
 29
 27
 28
 29
30
Filled surfaces – amalgam
 Correlation
 0.433
 -0.127
 0.550
 -0.144
 0.185
 0.541
 0.530
 -0.328
 -0.082
 -0.655

Sig. (2-tailed)
 0.019
 0.513
 0.002
 0.457
 0.337
 0.002
 0.004
 0.088
 0.673
 <0.001

N
 29
 29
 29
 29
 29
 29
 27
 28
 29
 29

a The upper part of the table (above the diagonal) shows the correlations using all cases (n = 30) and the lower part (below the diagonal) shows the correlations after exclusion of the case with previous occupational exposure to mercury (dental nurse, see text). P-values and number of cases included in the analysis are given. Significant correlations (p < 0.05) in bold.

Björkman et al. Environmental Health 2007 6:30   doi:10.1186/1476-069X-6-30