Benzene

Additional toxicological data

Administrative data

Endpoint:

additional toxicological information

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-guideline experimental study with clearly reported methods and results. Adequate for evaluation.

Data source

Reference

Reference Type:

publication

Title:

Ortho-quinones of benzene and estrogens induce hyperproliferation of human peripheral blood mononuclear cells

Author:

Chakravarti D, Zahid M, Backora M, Myers EM, Gaikwad N, Weisenburger DD, Cavalieri EL, Rogan EG and Joshi SS

Year:

2006

Bibliographic source:

Leukemia and Lymphoma 47, 2635-2644

Materials and methods

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Benzene

EC Number:

200-753-7

EC Name:

Benzene

Cas Number:

71-43-2

Molecular formula:

C6H6

IUPAC Name:

benzene

Details on test material:

Name of test materials (as cited in study report): benzene, benzene ortho-quinone

Results and discussion

Any other information on results incl. tables

BENZENE ORTHOQUINONE ADDUCT FORMATION

Both CAT-4-N7Gua (2.3 pmol/10^6 cells) and CAT-4-N3Ade adducts (0.6 pmol/10^6 cells) were detected when MNCs were treated with 75 uM benzene ortho-quinone.

QUINONE-INDUCED HYPERPROLIFERATION

Graphical data indicate that benzene ortho-quinone significantly increased the population of mitogen-induced MNCs following 7, 14 or 21 d treatment, with treatments of 25-100 uM being generally more effective at stimulating cell proliferation than 150 uM benzene ortho-quinone. The overall recovery of cells decreased during the course of the experiments (being especially reduced by  day 21) however a stimulatory response to the ortho-quinone was still apparent.

Applicant's summary and conclusion

Conclusions:

Benzene ortho-quinone stimulates proliferation of human peripheral blood mononuclear cells in vitro.

Executive summary:

The effect of benzene ortho-quinone (0-150 uM) on cell proliferation and DNA adducts formation in human mononuclear cells was investigated in vitro. Cell proliferation was significantly increased following 7, 14 or 21 d treatment although the extent of stimulation decreased with time. Both Catechol-4-N7Gua and catechol-4-N3Ade adducts were detected in cells exposed to 75 uM benzene ortho-quinone. The authors suggest that DNA damage induced by benzene ortho-quinone may promote growth of human blood mononuclear cells.