Cytotoxicity of water-soluble fraction from biodiesel and its diesel blends to human cell lines

The designation of biodiesel as a green fuel has increased its commercialization and use, making its fate in the environment a matter of concern. Fuel spills constitute a major source of aquatic pollution and, like diesel spills, biodiesel can produce adverse effects on aquatic environments, animals and humans. The present study assessed cytotoxic effects of water systems contaminated with neat biodiesel and its diesel blends by means of different procedures on human T cell leukemia (Jurkat) and human hepatocellular carcinoma (HepG2) cells [detection of changes in mitochondrial membrane potential (ΔΨm) using tetramethylrhodamine ethyl ester (TMRE), apoptosis recognition by Annexin V and impedance real-time cell analyzer (xCELLigence™ system)]. The data obtained showed concordance across the different bioassays, with cytotoxic effects observed as a dose-dependent response only for waters contaminated with pure diesel (D100) and B5 blend, which is characterized by a mixture of 95% diesel and 5% biodiesel. The data can also lead us to hypothesize that diesel accounts for the harmful effects observed, and that biodiesel does not worsen the impacts caused by diesel pollution.

► Biodiesel has received considerable attention in the recent past as a nonpolluting fuel.
► Fuel spills constitute a major source of aquatic pollution.
► Biodiesel's impacts on aquatic environments should be assessed due to lack information regarding this issue.
► Cytotoxicity assessments were performed on waters contaminated with diesel, biodiesel and their blends.
► Our data stressed that diesel was responsible for the cytotoxicity observed.
► Biodiesel does not worsen the impacts caused by diesel pollution.