Workers exposed to even low radiation levels run higher cancer risk

August 2, 2005

A study of radiology technicians shows that chronic exposure to ionizing radiation, even at low levels, raises the risk of basal cell carcinoma.

A study of radiology technicians shows that chronic exposure to ionizing radiation, even at low levels, raises the risk of basal cell carcinoma. The risk is even greater in those who have lighter eye and hair color, according to the study.

A research group from the National Institute of Radiological Sciences in Chiba, Japan, analyzed data from 65,304 white radiology technologists in the United States who completed surveys in 1983 to 1989 and in 1994 to 1998. The first survey asked respondents to answer demographic, health and work-related questions, while the second focused largely on cancer and related risk factors.

"Our study … provided indirect evidence of an increased risk of basal cell carcinoma associated with chronic occupational exposure to ionizing radiation at low to moderate doses," state the authors in their study, which was reported in a July issue of the International Journal of Cancer.

The study looked at a total of 1,355 cases of basal-cell carcinoma and 270 cases of squamous-cell carcinoma. Long-term exposure to ionizing radiation appeared to raise the risk of basal-cell (but not squamous-cell) carcinoma.

The effects were most pronounced for people who began working during the 1950s and earlier, a period when radiation exposure levels were relatively high.

Compared with technicians who started working after 1960, those who began in the 1940s were about two times more likely to develop basal-cell skin cancer. Technicians who began working in the 1950s were roughly 1.4 times more likely to develop basal cell cancer.