11 of the 12 apartment buildings worst hit by the explosions on Aug 12 in Tianjin have been given the highest rating for safety.
Large numbers of dead fish spotted offshore near the Tianjin blast zone have been examined and no hazardous cyanide compounds have been detected.
Commodity prices, including iron ore, increased after last week's fatal blasts in Tianjin affected operations at the city's port.
The fatal blasts in Tianjin last week have taught real estate developers to monitor closely what is planned for areas surrounding their residential complexes, the president of China's largest real estate developer by sales value has said.
The massive explosions in the port of Tianjin on Wednesday night destroyed thousands of imported cars that were waiting to be distributed.
Some property owners near the Tianjin blast site expect the government to buy apartments that were damaged by Wednesday's explosions, but government officials have not made such a commitment.
Authorities tasked with marine monitoring announced there were no hazardous chemicals detected in waters off the blast site in north China's port city Tianjin on Friday.
The massive warehouse blasts in north China's Tianjin have not affected arrival and departure of cruises from the port city, according to cruise companies and a trade association.
The air and underground water around the explosions in Tianjin are safe by Friday morning, said the experts at the news conference.
Harmful pollutants have been detected from two drainage outlets near the blast scene in Binhai New Area, says the Ministry of Environmental Protection.
Thousands of vehicles in a logistics park were destroyed during huge explosions late on Wednesday in the northern Chinese port city of Tianjin.
The average concentration of PM2.5, the airborne pollutants with a diameter of 2.5 microns, increased quickly, from 76 micrograms per cubic meter to 117 micrograms per cubic meter in the past 24 hours in a nearby station.