[The effects of occupational soluble chromate exposure on immunological function of T-cell]

To investigate the early changes of some immunological function of T-cell in chromate workers.

A total of 115 workers exposed to different levels of soluble chromate were enrolled in exposed group; while 90 non-exposure workers who lived far away from the chromate plant were enrolled as control. The air concentration of soluble chromate was determined by atomic absorption spectrometry. CD3(+), CD3(+)CD4(+), CD3(+)CD8(+) and CD4(+)/CD8(+) of T-cell were determined by flow cytometry analysis.

The individual air chromate concentration in the exposed group was (27.51 +/- 33.25) microg/m(3), and the control group was (0.16 +/- 0.15) microg/m(3). The significant difference between the two groups was observed (z = 8.045, P < 0.01). The levels of the lymphocyte subsets (CD3(+), CD3(+)CD4(+), CD3(+)CD8(+) and CD4(+)/CD8(+)) in exposed group were (30.08 +/- 17.75)%, (1.04 +/- 1.73)%, (11.94 +/- 9.78)%, 0.10 +/- 0.14. While, those of control group were (63.00 +/- 13.57)%, (30.51 +/- 5.16)%, (14.82 +/- 4.59)%, 2.17 +/- 0.53, higher than that of the exposed group (z values were 4.484, 5.227, 1.976, -5.218, respectively, P < 0.05).

On the basis of individual air monitoring, the cellular immune function affected by soluble chromate is mainly based on T lymphocyte inhibition. The indicators CD3(+)CD4(+) mentioned above may be considered as efficient biomarkers in further research.