"Hemp seeds represent the manufacturing starting point for the vast majority of hemp products marketed since the mid-1990s. Hemp seeds are a good source of essential fatty acids, primarily alpha-linolenic acid (omega-3) and ]inoleic acid (omega-6). They are also found in fish, flaxseed, rapeseed oil, pumpkin seeds, and sunflowerseeds. Essential fatty acids (EFA) are necessary fats that humans cannot synthesize, so they must be obtained through diet. EFAs support the cardiovascular, reproductive,immune, and nervous systems. The human body needs EFAs to manufacture and repair cell membranes, enabling the cells to obtain optimum nutrition and expel harmful waste products (9). THC found in manufactured products is present via contamination from resin produced in the leaves and buds that come into contact with the seed shell. Seed decontamination and manufacturing processes including wash steps and cold pressing for hemp products have improved since the mid-1990s, leading to the much lower THC concentrations currently found in today's commercial products.
"The presence of THC in these products has been a source of concern for the military and other workplace drug-testing programs. Ingestion of hemp products has been historically used as a defense in military and civilian trials for many years and continues today despite decreased concentrations of THC in hemp products (10-12). The Division of Forensic Toxicology, Armed Forces Institute of Pathology is often asked to analyze hemp products to determine their THC content in addition to rendering an opinion as to whether or not this THC concentration could be a reasonable cause for a positive THC metabolite urine analysis result."

Source

Holler, Justin M., Bosy, Thomas Z., et al., "Delta9-Tetrahydrocannabinol Content of Commercially Available Hemp Products," Journal of Analytical Toxicology, Vol. 32, July/August 2008, pp. 428-429.
http://jat.oxfordjournals.org…