How safe is Tianjin after explosions?
Tianjin residents have expressed concern about contamination
More than a week after a warehouse packed with hazardous chemicals exploded in the Chinese city of Tianjin, many are still scared that poisons lurk in the air, the ground or the water.
"It smelled strange when it rained yesterday," one Tianjin resident wrote online. "And I've been coughing for days. If the reports are true that there is nerve gas here, I'll wear a mask."
"Everyone living in Tianjin should avoid tap water," warned another. "Even if they say the pollutants have been contained, better safe than sorry."
How many of these worries are accurate? Is Tianjin still in danger? The short answer: we still don't know.
Forty chemicals were said to be in the warehouse, but the full list of chemical names has not been released.
The government says that the person in charge of warehouse logistics is too badly injured to speak, making it difficult to know exactly what was inside the warehouse at the time of the blast.
"No one knows for sure," explains Louie Cheng, a former chemical warfare expert with the US military who now runs an environmental health consultancy in China.
"They're mostly using records of what was known to have been in the warehouse. And we may never know what all was there. So, I can't say for sure if something is safe or not."
Dead fish
On Thursday, thousands of dead fish washed up on the banks of the Haihe River in the same district as the warehouse which exploded, sparking concerns online of mass contamination.
Officials said, however, that they had not found higher-than-average levels of cyanide in the water in the area.
They added that tests found there were low levels of oxygen in the water, indicating that the fish had died from hypoxia, which is the deprivation of oxygen.
Toxins posing a long-term threat, including potent carcinogens, could have been spread by the blasts.
Mr Cheng has been dealing with phone calls from worried customers living in Tianjin. "The questions that they're typically asking are: is it safe for us to be here? What are the long-term effects? Is it in the water? By and large, it comes down to: is it safe or not?"
He's advising his clients to stay indoors for the next two weeks and to use carbon-based air filters and masks that offer better protection against chemical exposure.
Workers have been disposing of damaged cars at the blast sit