Mercury has dramatically different toxicologic properties depending upon its chemical state. As a liquid metal, it was once used to cure constipation, apparently with few adverse side effects. On the other hand, mercury salts, which were used to form felt in the Dutch hat industry, led to the neurologic disorder renowned as being "mad as a hatter." Organic forms of mercury, such as methyl mercury, have proven to be even more pernicious, having caused hundreds of cases of paralysis and sensory loss along Minamata Bay in Japan. Inorganic mercury from a chemical plant became methylated in sediments and then bioaccumulated in shellfish. Because shellfish are the major protein source for much of the local population, this situation was an epidemic waiting to happen. Similar poisoning epidemics have occurred elsewhere (e.g., in Iraq and other countries where persons unknowingly ingested seed grain laced with organomercury fungicide). However, it was the Minamata disaster and its graphic depiction through Katagiri’s remarkable photographs in the late 1960’s that heightened global awareness of industrial pollution.