A specialist committee of the European Food Safety Authority (EFSA) has declared that manufacturing biodiesel is a safe way of disposing of so-called category 1 animal by-products, that could spread BSE or CJD.

EFSA's panel on biological hazards has concluded that because the material at the start of the production process is rendered and treated at 133Celsius for 20 minutes, "it may be concluded that the resulting biodiesel (and by-products) do not carry a TSE risk."

That said, the panel warned that bioassay tests on live organisms - conclusively proving its safety as regards TSE transmission - are impossible because of the general toxicity of biodiesel.