Radiation from Japan reaches B.C. shores, Simon Fraser University Media Release:
… The jet stream is carrying the radiation from Japan to North America. Most of the radioactivity disperses in the atmosphere and falls over the Pacific Ocean on its way over, but some of it has now reached the west coast, falling down with rain, and mixing with seawater. It’s also accumulating in seaweed.
The rainwater tested was collected at SFU’s campus on Burnaby Mountain and in downtown Vancouver, while seaweed samples were collected in North Vancouver near the Seabus terminal. Researchers began monitoring rainwater earlier this month but did not see the signature for iodine-131 in samples taken March 16 and March 18. However, they did detect the radioisotope’s signature in samples from March 19, 20 and 25.
Here are the results from the tests (measured in decays of iodine-131 per second per litre of rainwater – Bq/l):
* March 18: 0 (2) Bq/l
* March 19: 9 (2) Bq/l
* March 20: 12 (2) Bq/l
* March 25: 11 (2) Bq/l
Read the press release here.
Rainwater tests results from Vancouver, CA:
Read the test results here.
11 Bq/L is equal to 297.3 picocuries per liter. (Conversion calculator here)
The federal drinking water standard for Iodine-131 is 3 pCi/L. (Press Release)
Agency for Toxic Substances and Disease Registry for Iodine, CDC, April 2004:
EPA has set an average annual drinking water limit of 3 pCi/L for Iodine-131 so the public radiation dose will not exceed 4 millirem
Published: April 8th, 2011 at 8:20 am ET