If deep-sea divers ascend too rapidly from ocean depths, the decreasing pressure causes nitrogen to be released as gas bubbles in the blood  This condition is known as the bends
Sea snakes, who, like humans, breathe air that contributes nitrogen to the blood, are nevertheless able to make extremely rapid ascents and descents in ocean waters without suffering from the bends
Sea snakes, unlike humans, can excrete nitrogen from their blood into the sea by means of extremely small blood vessels beneath their skin.