Skipjack tuna addition, skipjack's livers were tested globally for tributyltin contamination. TBT is an organotin compound introduced into marine ecosystems through antifouling paint used on ship hulls, and has been determined to be very toxic. About 90% of skipjack tested positive for contamination, especially in Southeast Asia, where regulations of TBT use are less rigorous than in Europe or the US. Skipjack tuna is used extensively in Japanese cuisine, where it is known as . Besides being eaten seared () and raw in sushi and sashimi, it is also smoked and dried to make katsuobushi, the central ingredient in dashi (a common
USS Skipjack (SSN-585) got underway for sea trials off Charleston, before joining for four days of type training in the Jacksonville, Florida, area. She then sailed to her new home port, Norfolk, Virginia, before participating in Atlantic Fleet exercises. Early in February 1967, "Skipjack" got underway for sonar and weapon tests and then participated in Atlantic submarine exercises from March through June. July and August were spent in restricted availability at the Newport News Shipbuilding and Dry Dock Company following which "Skipjack" took part in FIXWEX G-67, an exercise designed to evaluate fixed wing ASW aircraft against a submarine with "Skipjack"'s characteristics. Following