By Na Jeong-ju

About 100 residents in Wolgye-dong, northern Seoul, might have been exposed to stronger radiation than the permitted level, a study showed Thursday.

Professor Ha Mi-na of Dankook University, who conducted the research, didn’t rule out the possibility that the exposure could cause cancer among the residents, urging Seoul Metropolitan Government to carefully monitor their health for decades to come.

“We conducted a survey on some 30,000 residents in the community for three months from December last year. It showed about 100 people might have been exposed to radiation that exceeded the radiation dose limit of 1 millisievert per year,” Ha said. “The radiation levels in the area are possibly hazardous to human health.”

The finding came after higher-than-normal levels of radioactivity were detected on an asphalt-paved road in the area in November last year. The asphalt was found to contain radioactive materials, including cesium-137, but the Nuclear Safety and Security Commission claimed at the time that the radiation levels were not harmful to humans.

“Being exposed to radiation levels higher than 1 millisievert per year means that one person per 10,000 to 100,000 could get cancer from the exposure,” Ha said.

The municipal authorities have removed the asphalt and repaved the road, but residents and environmental groups have raised concerns about possible health risks. The radiation levels in other areas in Seoul were much lower than the annual dose limit.

The city government said it will conduct checkups on all residents and take necessary measures to address their concerns.

The commission said last year residents around the contaminated road were exposed to 0.51 to 0.69 millisieverts of radiation, which is not harmful to either adults or children.

However, the Korea Federation for Environmental Movements claimed the commission measured the level in the air 1 meter above the ground, saying the radiation levels exceeded 3 millisieverts when measured on the surface of the asphalt.

Last year, Seoul City investigated 16 companies that produce asphalt for roads but did not detect any higher than normal radioactivity levels.