Minute traces of cyanide have been detected in water samples collected near the Tianjin Port, the State Oceanic Administration (SOA) said Monday.

The monitoring reports, showing traces of the chemical, were from Sunday according to the SOA. The density of the dangerous chemical was below the normal limit, and will not pose a threat to the marine environment for the time being.

Thirteen monitoring sites have been set up in the waters off Tianjin Port and the sea area east of Dongjiang Port, both in the municipality. A total of 194 samples were collected and minute traces of cyanide were detected at two sites in Tianjin Port.

The SOA said it would continue monitoring and release the related information in a timely manner.

Officials with Tianjin bureau of environmental protection said that the roughly 700 tonnes of sodium cyanide that had been stored at the site "remained mostly unaffected".

Two massive explosions, which occurred in the port city in north China just before midnight on Aug. 12, have devastated a large area surrounding the incident.

Environmental authorities set up 27 additional water monitoring spots, three of which reported excessive levels of cyanide, with some samples containing 27.4 times the normal limit. Two of the original monitoring stations reported cyanide levels of 1.25 to 2.2 times the standard.

Sodium cyanide at the periphery of the blasts area will be mostly collected and cleared by Monday evening, assured He Shushan, vice mayor of Tianjin, on Monday.

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