(562) Water soluble poisons are excreted by the kidney in the urine. Other poisons are first detoxified in the liver into water soluble compounds and then excreted in the urine. Some poisons are detoxified in to non-water soluble substances which may then be combined with other substances to neutralise them further. Fat soluble poisons are likely to accumulate in the liver. Poisons may also be excreted through the skin or through the milk with possible adverse effects on sucking piglets. Some may be absorbed across the placenta of the pregnant sow and affect the foetus. Tissues used for testing include liver, kidney, blood and stomach contents.