Biodiesel, a partially renewable agrofuel, generates fewer greenhouse gas emissions than gasoil, but could have negative impacts on marine life, warns a study by Brazil’s Universidade Estadual Paulista. The researchers exposed two species of fish, Nile tilapia (Oreochromis niloticus) and armored catfish (Pterygoplichthys anisitsi) to pure biodiesel and two gasoil mixtures, one with five percent agrofuel (B5) and the other with 20 percent (B20), for periods of between two and seven days.

"The effects of B20 were less pronounced than those of gasoil and B5, but even pure biodiesel activates biomechanical responses," research project leader Eduardo Alves de Almeida told Tierramérica.

"Biodiesel also causes, and in a more aggressive way, the oxidation of the cell membranes of the fish’s gills, and facilitates the entry of other toxic substances," he added.