DHA-CoA preferentially moves back to the ER, perhaps as a free fatty acid. This conversion is usually catalysed by acyl-CoA thioesterases (ACOTs). No specific acyl-CoA thioesterase enzyme has been identified for the peroxisomal metabolism of DHA-CoA, but the peroxisomal ACOT8 has a wide substrate specificity and is likely to be responsible (Ferdinandusse et al. 2003, Hunt & Alexson. 2008).