In vitro myelotoxicity of environmental contaminants.

Myelotoxicity of pesticides and algal toxins was detected in vitro by using the granulocyte-macrophage colony forming unit assay (CFU-GM), and the MTT test with SR-4987 cells, an established stromal cell line derived from a long term murine bone marrow culture, which may represent a suitable in vitro model for studying haematotoxicity. Comparison of the IC50s and NOELs obtained with the CFU-GM assay and those determined by testing the established stromal cells in the MTT cytotoxicity test indicate that inhibition of the proliferation of SR-4987 stromal cells is a sensitive in vitro endpoint for measuring myelotoxicity. It is suggested that this assay could be used as rapid and easy screening test for determining the haematotoxicity of environmental toxins. A comparison with results obtained with the MTT test on a non-differentiated cell line, 3T3-L1, was carried out to distinguish between non-specific interference with cell proliferation and specific toxicity on haemopoietic cells.