Ecotoxicity assessment of camphor oxime using Microtox assay – preliminary research

The ecotoxicity assessment of new substances is crucial for their considered launch on the market. Due to various properties of chemical compounds, however, the application of biotests can be challenging. In the case of insoluble compounds, a proper, non-toxic solvent must be applied. The presented preliminary results demonstrate the extremely high ecotoxicity of camphor and camphor oxime, assessed by means of the Microtox system. A 81.9% Basic Test with 14 dilutions was applied. The ecotoxicity of a solvent (i.e. DMSO) was also assessed. The initial concentration of substances was 5%. EC 50 values reached 0.00023% and 0.00007% for camphor and camphor oxime, respectively, after 15 min. of incubation of the samples with bioluminescent bacteria. The ecotoxicity of the solvent remained negligible. Due to the extremely high ecotoxicity values of the tested substances, another range of concentrations needs to be applied in future tests to confirm the results.