Although toxic chemicals have been detected in the air following the massive explosions in Tianjin, city officials insist that the pollutants are still well within normal levels.
Toxic fumes detected in the air after the blasts in the Tianjin Binhai New District are within national standards, Wen Wurui, head of Tianjin's environmental bureau, told the media on Thursday.
Local authorities have installed 22 temporary monitoring stations around the blast site to monitor air and water quality immediately after the explosions. At 4 p.m. on Wednesday, police detected large amounts of toxic gases, including sulfur dioxide, carbon monoxide and nitrogen oxide within 500 meters of the fire, but they were not detected two kilometers away.
Samples collected at 4 a.m. the next day showed that less than 2 milligrams per cubic meters of epoxythane, a carcinogenic gas, was found in the most polluted areas. Epoxythan is considered hazardous at concentrations of 5 milligrams per cubic meter.
At 5:30 a.m., concentrations of toluene, widely used in industrial feedstock and solvents, were at 5.7 milligrams per cubic meter, exceeding the city's standards of 2.0 milligrams per cubic meter, the China Daily reported on Thursday. Methylbenzene and volatile organic compounds, both harmful gases, were also detected to have slightly exceeded safety standards.
As of 11 a.m. on Thursday, all toxic gas indicators were within their normal range.
Drainage outlets to the sea had also been closed and special anti-chemical warfare troops deployed on site, the Tianjin Daily reported.
In neighboring Beijing, local authorities denied rumors that the blast has affected the air quality in the capital.
The capital is currently seeing wind from the southwest and west, and Tianjin is located in the southeastern direction, so the pollutants from the blast will go to the Bohai Sea and have no influence on the capital, the Beijing Environmental Protection Bureau said on Thursday.
Located in China's northeastern coastline, Tianjin is still reeling from the explosions that rocked the port city on Wednesday. Fires are still reportedly burning at the blast sites in a port area owned by Ruhai Logistics, a company that specializes in hazardous materials, according to the BBC.
At least 56 people died and more than were 720 injured, with 25 in critical condition, officials said.