Sunday marks 60 years since doctors in Japan discovered a neurological disease in the town of Minamata, caused by one of the world’s worst cases of toxic dumping.

In 1932, the Chisso Corporation, an integral part of the local economy for over a century, began to manufacture acetaldehyde, used to produce plastics, in their chemical plant in Minamata.

Mercury from the production process began to spill into the bay.

Inhabitants of Minamata started to show strange symptoms. They were shouting uncontrollably, slurring their speech or dropping their chopsticks at dinner.

As it was later discovered, they were slowly being poisoned by mercury that found its way into their food.

The mercury was discharged for decades, continuing even after illness was linked to it.

Fighting for compensation

Exhibits in the town's museum chart how the practice went on until 1968 - 12 years after the disease was first diagnosed and nine years after experiments on cats confirmed mercury poisoning as its cause.

Today, more than 2,000 residents of Minamata are officially recognised as "Minamata patients" and they are receiving continuing support.

About 2,000 others are still fighting for that status, and 70,000 defined simply as “sufferers” are entitled only to help with medical bills.

Kenji Nagamoto is one of the town residents who was recognised as a "Minamata patient."

He has been battling the disease since he was born and today he is working in a daycare centre to sustain his ability to walk.

"I am the only person here who can still walk," he told Al Jazeera.

"When I think about the feeling of others who can't, it makes me think that if Chisso had stopped dumping mercury earlier, none of this would have happened."

A clean-up operation costing hundreds of millions of dollars has, authorities say, restored the waters to the purest standards.

But Minamata's residents still feel their town's dark legacy.

"Our physical conditions and symptoms change daily. The company and the authorities may be able to help us financially, but they can’t save our hearts," said Masami Ogata, another "Minamata patient".