The north China port of Tianjin is getting back to normal after last Wednesday's explosions.

The cleanup operation at the core area of the explosions is progressing, Wang Hongjiang, vice mayor of the north China municipality, told a conference on Friday afternoon.

So far, 200 tonnes of sodium cyanide has been collected and removed from the site and the focus will now shift to metallic sodium and magnesium.

Over 3,000 tonnes of polluted water from the core blast area have been removed from the area and treated, Wang said.

The water supply was cut off immediately after the explosions to ensure that tap water remained unaffected and sewage pipes were blocked.

"Contamination at the core blast area is now under control, and the surrounding area is safe," the vice mayor confirmed.

Cyanide levels in samples from rivers and offshore were below toxic levels. Air quality in the area is no different from that reported across the municipality, said Deng Xiaowen, head of the city environment monitoring center.

Deng dismissed the huge number of dead fish along the banks of the Haihe River to oxygen deficiency rather than poisoning.

Tianjin has conducted safety audits of 275 companies since the explosions, 70 of which were found to have safety problems and have had their operations suspended, according to the head of Binhai New Area, Zhang Yong.

The blasts have affected 17,000 households to varying degrees, leaving at least 6,300 in temporary housing. Almost all of those people have now left. Migrant workers were given payments to help them go home and others have turned to their relatives. Only around 100 people are still staying in the temporary shelter now.

The train station from downtown Tianjin was destroyed in the blasts, and rebuilding cannot start immediately. Shuttle buses will be used until the train service resumes, perhaps in early October.

With the new semester approaching, schools near to the blast site will not delay their opening, Zhang said, adding checks and repairs to school buildings will ensure the safety of the students.

Zhang said that 365 enterprises registered in the district from Aug. 13 to 20, 17 of which are foreign-funded enterprises.

"This reflects that enterprises at home and abroad still have confidence in the development of Binhai New Area," Zhang said.

The government will help the affected companies in the blasts to resume production as soon as possible, he said. Initial estimates say the blasts have affected 1,700 enterprises.

Last Wednesday night, two explosions destroyed the warehouse in Tianjin where hundreds of tonnes of toxic chemicals were stored, including roughly 700 tonnes of sodium cyanide. As of Friday afternoon, 116 people have died, 646 remain hospitalized and 60 are still missing.

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