In this article, cellulose acetate produced through the homogeneous acetylation of sugar cane bagasse cellulose was used to produce membranes, using poly( ethyleneglycol) 600 ( PEG 600) as an admixture. The membranes were characterized using water flux measurements (Payne's cup), differential scanning calorimetry ( DSC) and neutral red uptake ( cytotoxicity). The results showed that PEG 600 acts as a crystallinity inductor and/or pore former in the cellulose acetate matrix. The induction of crystallinity is important for this system since it had not been reported on the literature yet. The results also demonstrated that the studied membranes present a nontoxic behavior.