Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Measured data are not available for the terrestrial toxicity endpoints. In accordance with column 2 of REACH Annex IX and X, the terrestrial toxicity tests do not need to be conducted if direct and indirect exposure of the soil is unlikely to occur. Acetylene is a gas at standard temperature and pressure and is expected to partition primarily to air. An indicated Kow of 0.37 would also indicate low potential to bioaccumulate therefore terrestrial toxicity tests are not required.

In the absence of measured data the ECOSAR ECOWIN v1.00 model (Nabholz and Mayo-Bean 2009) has been used to calculate the toxicity of acetylene to earthworms. The ECOSAR model is a reliable and appropriate QSAR model to apply to acetylene as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity. The 1-day LC50 for earthworms is estimated to be 67 ppm.