AbstractSkin symptoms of “Yusho” and their change thereafter are described. In the early stage, skin eruptions were the most prominent and impressive features of Yusho. Acneiform eruptions and pigmentation were most conspicuous. With the passage of time, there is some improvement and most patients now have few eruptions, except for the severely intoxicated group. As for blood PCB analysis, the severely intoxicated group who showed intensive skin symptoms showed “pattern A”—a typical specific Yusho pattern. The blood PCB patterns of each patient were stable with no alteration after many years and, on the other hand, the blood PCB concentrations have diminished yea