China's State Oceanic Administration reported Thursday the appearance of several new oil slicks in the East China Sea linked to the sinking of an Iranian oil tanker that occurred last week.

The four new oil slicks were spotted by Chinese planes, vessels, and satellites, and appear in the same area where the Sanchi oil tanker collided with a Chinese vessel.

The collision, which resulted in the deaths of all 32 crew members aboard the Sanchi, ranks among the worst ship disasters in decades.

Sanchi is estimated to have been carrying 8,450 barrels of bunker fuel at the time of its collision. The tanker was also carrying 136,000 tons of ultra-light crude oil. Both types of fuel pose an environmental danger to marine life in the area.

Chinese authorities and environmental groups continue to monitor the slicks.

"At this time of the year the area is used as a wintering ground by common edible species such as hairtail, yellow croaker, chub mackerel and blue crab," Environmental group Greenpeace said a statement last week. "The area is also on the migratory pathway of many marine mammals, such as humpback whales, right whales and grey whales."

Zhu Xiaohua, a researcher at the State Oceanic Administration's Second Institute of Oceanography said pollutants from the spill could be carried far into the Pacific Ocean by currents.

"It will definitely be possible to detect sole pollution particles from the Sanchi along America's West Coast in the future," he told the South China Morning Post.