How bad could the North Sea tanker collision be for the environment?

London — The Monday collision between a cargo ship and an oil tanker in the North Sea “has a high risk of being an environmental disaster in really important protected areas,” Naomi Tilley, Oil and Gas Campaign Lead at Oceana U.K., an environmental group focused on oceans, told CBS News on Tuesday.

The U.K. Coastguard said an exclusion zone of about half of a mile had been established around both vessels, which were no longer stuck together.

“At this stage, it’s too early to assess the extent of any environmental damage,” Greenpeace U.K. said in a statement early Tuesday, explaining that the severity of any impact would depend on a number of factors, including “the amount and type of oil carried by the tanker, the fuel carried by both ships, and how much of that, if any, has entered the water.”

The U.K. Coastguard said its Counter Pollution and Salvage Team was “assessing the situation” and “developing a plan ready for implementation as soon as the situation allows.”

Air quality in the area was reported to be normal, and there was a “very low” public health risk on nearby shores, according to the U.K. Health Security Agency.

“It’s really hard to know at this stage what is in the water and how that’s going to behave, but almost in any circumstances, it’s bad news,” Tilley told CBS News.

Tanker collision near protected marine areas

The North Sea is home to a number of protected marine animals, as well as vital fishing stocks for the U.K. and other European countries.

Oceana U.K. believes the collision took place near two protected areas in particular, including the Southern North Sea marine protected area, which is designated to protect the harbor porpoise, Tilley said.

“It’s a really important area of breeding and a really large portion of the global population is found in that area,” she said.

The harbor porpoise is a “species that needs to come to the surface to breathe, so it won’t easily be able to avoid slicks on the surface,” Tilley told CBS News.

The Holderness Offshore marine protected area, meanwhile, is designated for the safety of sea floor habitats.

“It’s got ocean quahogs, which live for centuries. They’re kind of these clams that are really long-lived. And starfish and underwater sponges and things… They’re both really important parts of the sea and they’re very close, if not where this incident has happened,” Tilley said.

Possible contaminants

Both of the vessels involved in the collision would have had their own fuel for propulsion, and the American tanker that was hit, the MV Stena Immaculate, was also transporting jet fuel, according to Crowley, the U.S. logistics group that operates the vessel.

Jet fuel is toxic for marine life, and Crowley said some of it had been released in the crash.

“The Stena Immaculate sustained a ruptured cargo tank containing Jet-A1 fuel due to the collision,” Crowley said in a statement to the Reuters news agency. “A fire occurred as a result.”

It was still unclear Tuesday how much jet fuel had been released and how much might already have burned off in the fire.

Initial reports indicated that containers carrying sodium cyanide were on board the other ship, a Portuguese-flagged cargo ship called the MV Solong. Sodium cyanide is a toxic substance that evaporates quickly and could have created dangerous air conditions on the surface of the water for cleanup crews and animals.

The shipping company that operates the vessel, however, Ernst Rust, said Tuesday that there were no containers containing sodium cyanide on the Solong, but that there were four that had previously contained the chemical and they were being monitored.

Potential risks to fishing industry – and consumers

Tilley said pollution from the collision could impact fish stocks in the North Sea and the people that rely on them.

“The North Sea is a hugely important area for U.K. fishing fleets, but also European fishing fleets,” Tilley said. 

The extent of any environmental contamination is still unknown, she said, but it “could have really long-term impacts for the community, like whether the chemicals end up in the water. If that impacts the fish stocks and the population of fish that we eat, then that could have an impact on the fishing industry.”

Tilley noted that previous large oil spills had “resulted in quite an enormous area where fishing wasn’t allowed because of contaminated fish for quite a long long time.”