March 27, 2011

By Katheleen Conti, Staff
Boston Globe

Low levels of radioactive iodine likely resulting from the nuclear accident in Japan have been detected in a sample of rainwater in Massachusetts, state health officials said today.

The amounts of radioiodine are very low concentrations and should have no impact on state drinking water supplies, John Auerbach, commissioner of the Department of Public Health, told reporters.

The rain sample was taken during the past week in Boston as part of regular monitoring of radioactivity on the environment by the US Environmental Protection Agency. No detectable increases in radiation have been discovered in the air, Auerbach said, and there are no expected public health concerns.

"The drinking water supply in Massachusetts is unaffected by this short-term, slight elevation in radiation," he said. "However, we will carefully monitor the drinking water as we exercise an abundance of caution."

Radioiodine is a by-product of nuclear energy production and has a half-life of eight days, Auerbach said at a press conference this afternoon at the William A. Hinton State Laboratory Institute in Jamaica Plain. Half-life means that only half of the level of radiation will be present in eight days, and so on until it completely dissipates.

"That means it should be undetectable in a matter of weeks, assuming that there is no new source of radiation exposure," he said.

Drinking water samples taken last week from the Quabbin and Wachusett reservoirs showed no detectable levels of radioiodine. Precautionary samplings from 12 other water supply sources across the state were taken today. Results are expected over the next several days.

Similar levels of radiation in rainwater samples have been found in other states, including California, Washington, and Pennsylvania, Auerbach said.

The 9.0-magnitude earthquake and subsequent tsunami that struck northern Japan on March 11 seriously damaged the six-reactor Fukushima Daiichi nuclear complex, which continues to spew radiation into the atmosphere and the sea.

Harmless traces of radiation from the stricken nuclear complex in Japan have been detected wafting over the East Coast of the United States, the New York Times reported last week. The paper cited European officials who have tracked the radioactive plume as it has drifted eastward on prevailing winds from Japan – first to the West Coast and now over the East Coast and the Atlantic, moving toward Europe. The plume’s radiation had been diluted enormously in its journey of thousands of miles and that – at least for now, with concentrations so low – its presence will have no health consequences in the United States, the paper reported.