> 173 fatalities
> Destruction of civil infrastructure within a 1-km radius
> Cyanide pollution
> Site rehabilitation
Fire broke out at 10:50 pm at the site of a logistics company, operating since 2011 in the Tianjin port sector with a floor area covering 46,000 m². At the time of the accident, the company had been storing on-site several types of hazardous substances: calcium carbide, toluene diisocyanate, ammonium nitrates, potassium and sodium, as well as 700 tonnes of sodium cyanide.
As fire-fighters were attacking the blaze with water, 2 explosions occurred around 11:30 pm. The first had the equivalent force of 3 tonnes of TNT, while the second was more powerful at 21 tonnes. A tremendous plume of smoke formed, followed by a massive fire. The resultant emergency response comprised several thousand fire-fighters, soldiers and police officers.
On 21st August, a full 9 days later, 4 new fire outbreaks occurred adjacent to the sites of the explosions.
Extensive human and property losses
The consequences of this accident were significant and became exacerbated during the days following the explosions, particularly regarding human, property and environmental considerations. The extremely high human toll stood as of 15th September 2015 at 173 deaths, 720 injuries and 70 missing (mainly fire-fighters).
As for property loss, 17,000 housing units sustained damage and 6,000 residents were displaced. Window panes were shattered on buildings within a 3-km radius. A rail transit station located 650 m from the site of the explosion was also devastated. Operations at Tianjin Port’s methane terminal (handling 3 billion m³ of LNG a year) were disrupted by the accident, which in turn interrupted China’s natural gas supply for several months. An initial damage appraisal yielded a figure of between 1 and 1.3 billion euros.
Causes reported by the media
The company had been known to authorities for its breaches of safety rules. One of its shareholders is thought to have used his political influence to obtain the administrative permits required to operate the facility.
The warehouse was located 500 m from the nearest residences, even though Chinese regulations stipulate that warehouses containing hazardous products be placed at least one kilometre from residential districts.
The lack of emergency response preparation was also cited. Fire-fighters deployed water hoses not knowing that some of the products being stored react violently in contact with water. In particular, sodium cyanide can transform under these conditions into hydrogen cyanide, a lethal gas at very small doses.
The post-disaster response
Unlike an insecticide or herbicide, cyanide attacks all the cells of any kind of organism (algae, mammals, mushrooms, fish, etc.). The entire food chain is thus threatened, along with the major risk of inducing an ecosystem imbalance.
To better manage the spread of pollutants, a confinement perimeter was set up over a 3-km radius around the accident site. Sandbags and earth dams were built in order to contain a 100,000-m² zone on all sides of the deflagrations. The objective here was to avoid any liquid leak.
According to Chinese authorities, sodium cyanide was found 1 km from the accident site. Pieces of damaged containers were also examined to remove the toxic substances. A French specialist firm was commissioned to treat the zone’s wastewater by means of oxidation: the cyanide was transformed into cyanate for subsequent neutralisation.
On 19th August, Tianjin’s Environmental Protection Office declared that the level of cyanide found in the river running adjacent to the site as well as in the sea at the periphery of the evacuation zone had exceeded the tolerance thresholds by a wide margin.
In France, trade union organisations in the maritime transport sector expressed concerns over the human health consequences from the accident, especially on merchandise being stored in boats docked at the Tianjin Port.
Site rehabilitation steps
Clean-up operations in the explosion zone were officially completed around mid-September 2015. A site rehabilitation project in the form of an eco-park was being promoted by authorities (with construction planned for mid-2016). Moreover, Tianjin authorities announced that they would buy back all destroyed dwellings from their owners, with the buyback amount equalling either 1.3 times the price appraised on 11th August (i.e. the day before the explosions) or the original purchase price, whichever is higher.