State health department monitoring shows the trace levels of radioactive iodine from Japan are dropping in Washington. The Department of Health testing for the material in air, rainwater and milk shows no public health risk.

State health officials began looking for radioactive iodine in the air after the March nuclear reactor emergency in Japan; trace levels of radiation in the state were expected. On March 20 a very low trace level of radioactive iodine (I-131) was detected in an air sample from the Seattle-area monitor. Levels have sharply declined (www.doh.wa.gov/Topics/japan/iodine.htm) since.

This monitoring is in addition to the routine air monitoring around the state for the normal background radiation; levels of this radiation have not increased, and remain in a normal range. Radioactive iodine is not part of the natural background radiation found in the environment, and is evidence that small amounts of radiation from Japan have come to Washington state.

Other test results are on the agency’s Japan earthquake Web site: www.doh.wa.gov/Topics/japan2011.htm.