E Minamata disease Q&A

1. Outbreak & Cause

Q4: How was the cause of Minamata disease revealed?

A4: It was demonstrated by a lot of research including studies on the patients, animal experiments, chemical analysis, etc.

Commentary:
At first, since the majority of the patients were fishermen who ate large amounts of marine products, and the neighboring cats also showed abnormalities, it was suspected that polluted fish might be a cause.
Later, the cause of Minamata disease was identified as methylmercury based on the findings such as: 1) the characteristic symptoms shown by the patients, 2) the detection of mercury in urine from the patients, 3) the experimental results of cats given methylmercury-contaminated food, and 4) detection of methylmercury in the wastewater of Chisso's factory.