Worst marine pollution

According to Official Guinness Records,

A fertilizer factory on Minamata Bay, Kyushu, Japan, deposited mercury waste into the sea between 1953 and 1967. Up to 20,000 people were affected, 4,500 seriously. 43 people died from the poisoning;another 800 deaths were attributed to mercury poisoning by some sources, while 111 others suffered permanent damage.

For a complete list of 1953 records, please visit 1953 Guinness Records in Japan.

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