Two days after an "apocalyptic" explosion [5] in the port city of Tianjin killed at least 50 people and vaporized a bit of excess auto inventory [6], Chinese officials are struggling to explain what happened and reassure a nervous public.
The blast - footage of which is reminiscent of a nuclear detonation - likely stemmed from what The New York times called a "witches brew" of toxic chemicals warehoused in the industrial zone. That has residents on edge, as many wonder if the air is safe to breathe. Here’s The Times [7]:
They wondered if even the air was safe because of the smoke, still billowing hours later from vestiges of the inferno, which destroyed an industrial zone near the port. Many people wore masks.
“Right now, we don’t know anything,” said Sun Meirong, 52, an office cleaner who descended 13 flights of stairs with her 1-year-old grandson after the explosions blew in her apartment windows and front door.
Questions loomed over the precise reasons the chemicals had ignited, detonating in frightening fireballs that registered on earthquake scales, engulfed hundreds of new cars awaiting export and shattered windows in high-rises a mile away.
At least one chemical known to have been stockpiled at the site, calcium carbide, can emit flammable gases when it becomes wet. Some outside experts speculated that firefighters, in their effort to douse the flames, may have inadvertently contributed to the explosions.
“If enough water gets in there, calcium carbide is going to very quickly decompose,” said Chris Weber, president and chief executive of Dr. Hazmat Inc., a hazardous-chemical consulting concern in Longmont, Colo. “The most likely and most violent reaction would be the calcium carbide.”
On Thursday afternoon, the site still smoldered as Tianjin officials, unsure about the nature of the chemicals, let the blaze extinguish on its own.
According to the Tianjin Tanggu Environmental Monitoring Station,calcium carbide was one of several toxic industrial chemicals stored by the company. The others included sodium cyanide, which can produce hydrogen cyanide, a volatile and flammable liquid; and toluene diisocyanate, which can also react violently in the presence of water.
In a statement on Thursday, Greenpeace warned that the chemicals threatened human health. It said that sodium cyanide, used in mining, is especially toxic, while toluene diisocyanate, used to make polyurethane products, is a carcinogen.
With rain forecast for Friday, Greenpeace also warned about the danger of airborne pollutants seeping into groundwater.
Even Chinese media admits that determining exactly what was stored at Tianjin and thus what may or may not now be in the air and water is at this point largely impossible. Via Xinhua [8]:
The dangerous chemicals stored in the warehouses that exploded on Wednesday night in Tianjin Port can not be determined at the moment, authorities said at a press conference on Friday.
Gao Huaiyou, deputy director of Tianjin's work safety watchdog, cited major discrepancies between the accounts of company management and customs, and damage to the company's office as reasons they are unable to identify the chemicals.
And while it's apparently too early for China to order that the media stop reporting anything negative about the explosion in Tianjin just as they did about last month's explosion in equity markets, it does look like efforts to "clean up" the mess (in a literary sense) have begun. From People's Daily [9]:
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.
A statement from the State Oceanic Administration (SOA) said major measurement of seawater composition did not show any anomaly compared with historical records.
Hazardous materials such as cyanide and volatile phenol were not detected, while the variety of zooplankton was not affected either, it added.
The results were made after 177 seawater samples were taken by local marine monitors in Tianjin. The SOA said it will update seawater status if major changes are found.
One would certainly think that any endeavor to determine if chemicals from the warehouses had leaked into the ocean would be complicated by the fact that authorities aren't yet sure what chemicals they're trying to detect, but in any event, we certainnly imagine that the "fallout" (both literally and figuratively) from Wednesday's disaster will be difficult to cover up and may show up in a few very unpredictable places.
