Radioactive material from Japanese nuclear plant detected in Michigan airAgency: Environmental Quality
March 30, 2011 11-03-02
Detected levels pose no health threat
The Michigan Department of Environmental Quality has detected very low concentrations of iodine‑131, a kind of radiation released from the nuclear power plant in Japan, in an air sample taken over the past week.
The levels detected in Michigan pose no health threat to residents.
The DEQ's Radiological Protection Program performs regular monitoring of air samples taken in Lansing. The air sampler runs continuously, processing 50 liters of air per minute for a total of 504,000 liters last week. The average human uses 7 liters of air per minute. Air monitoring staff change the air sampler filters each Monday morning and analyze the filters in DEQ's radiological laboratory.
Monday's lab results indicated a total activity of 23 picocuries or 0.85 becquerels of iodine-131, a signature radioactive isotope for Japan's nuclear power plant emergency. These are scant detection levels, even when compared to the radiation levels people are exposed-to every day. For example, a typical banana contains 15 becquerels of potassium 40, a common radioactive isotope.
Officials at the Michigan Department of Community Health said the scant levels detected by DEQ monitors are thousands of times less than what would trigger any sort of protective action recommendation, such as taking potassium iodide, a drug that protects the thyroid gland from radioactive iodine.
During the height of the Chernobyl nuclear disaster in 1986, the DEQ measured iodine-131 levels that were 4 times higher than the current results. Even at those levels, the resulting dose to Michigan residents was thousands of times less than the activity triggering protective action recommendations.
The DEQ has conducted regular monitoring of air, milk and rainwater for radiological detection since 1958.