The spill is expected to affect over 1 million people living in 70 Russian cities and villages along the Amur River, along which the slick is moving.
Russian officials say the situation is under control and some have tried to calm local residents by drinking glasses of tap water in front of the cameras.
In preparation for the spill, a first shipment of 20 tons of active charcoal to purify water was delivered to Khabarovsk yesterday. Officials are considering ordering another 200 tons.
Local inhabitants, however, remain jittery. They have been stocking up on bottled water and disposable cutlery, and many are fleeing the region.
Reports by environmental groups are, indeed, not reassuring.
Ecologists call the spill a "catastrophe" and say it will kill most of the fish in the Amur River.
The pollutants are expected to take about five days to pass through Khabarovsk -- but this does not mean the water will then be safe to drink.
Ilya Mitasov, a spokesman for the World Wide Fund for Nature (WWF) says a second toxic wave will hit the region when the river's contaminated ice melts next spring.
"Other effects of the pollution can be established in the spring, when the ice will melt and toxic substances will pour into the water. This will affect the biological diversity of the Amur River's ecosystem as well as human health," Mitasov says. "We know that if benzene is absorbed by the human body, it can cause severe headaches and, in very high concentrations, blindness."
Along with benzene, other toxic substances such as aniline, nitrobenzene, and xylene have been found in Chinese waters after the blast. These chemicals are all dangerous to humans -- some are carcinogenic and others can damage the neurological and reproductive systems.
Environmental groups, however, say such spills are all too common in Russia's Far East region. In a report issued on yesterday, the WWF said chemicals are regularly dumped into rivers by both Chinese and Russian industries.
As a result, the incidence of waterborne diseases such as dysentery and hepatitis A in Russia are twice as high as the national average.
The WWF report describes some stretches of the Amur as "heavily polluted" and Mitasov says environmental groups have long cautioned against eating fish from this river.
Aleksei Yablokov, the director of the Center for Russian Environmental Policy, says poor ecology in the region underscores Russia's total lack of environmental protection policy.
"Our government policy is going in the other direction. Our policy is called state 'de-ecologization.' It does not care about the future, about consequences. It is directed towards making quick profits," Yablokov says.
Yablokov says that big cities are now well prepared for the spill but that little has been done to protect the region's smaller villages. Consequences in these villages, he warns, could be "terrible."
WWF's Mitasov, however, puts a positive spin on the looming ecological catastrophe.
He hopes the work of the special Russian-Chinese governmental unit formed to coordinate the response to the spill may provide a basis for jointly curbing routine pollution in the future.
"We consider that its [the commission's] work can be used as a basis for a joint program towards a rational environmental policy," says Mitasov. "I think that the catastrophe will push both Russian and Chinese authorities to think about the water purification system and the control of companies that pollute this water. Unfortunately, we learn from our mistakes."
The Amur basin is home to many rare and endangered species such as tigers, leopards, and musk deers.