This product is an ideal standard for analysis and for use in biological systems. Docosahexaenoic acid (DHA) is a major component of fish oils, animal phospholipids, and algae. Supplements of this acid are widely popular due to possible improvements in cognitive and behavioral functions, sight defects, inflammation disorders, and cancer.1 It is essential to many neurological functions and is present in very high levels in the mammalian brain, brain synaptosomal plasma membranes and synaptic vesicles. It is essential for the early neural development of mammals2 and it inhibits the rostaglandin synthase-cyclooxygenase enzymes. DHA is the precursor of the docosanoids which have potent anti-inflammatory and immuno-regulatory actions. In the retina it is a major structural component of the photoreceptor outer segment membranes. DHA can depress prostaglandin E2 production and, along with EPA, has been shown to cause a significant growth inhibition of human lung carcinoma.3