Rapid bleach for melanin.

Complete bleaching of melanin in strongly pigmented specimens embedded in paraffin or polystyrene, and sectioned and mounted on slides, is possible in 1-3 hr at 37 C in a solution of 20 ml of benzyl alcohol, 10 ml of acetone, 5 ml of 10% hydrogen peroxide and 4 drops of a 25% ammonia solution. The bleached tissues are well preserved and tolerate further histochemical treatments. All the stains and reactions tested give results identical to or better than those obtained after 24-48 hr oxidation in 10% hydrogen peroxide.