Latest RIU simulation reveals that Philippine Cs-137 activity may approach 1-10 Becquerel within the next few days

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Cs-137 has a half-life of around 30 years, so expect this stuff to hang around for awhile.  The probability of isotope ingestion increases significantly with rainfall.

Simply put, we can expect as many as ten Cs-137 atoms disintegrating around our personal space (m3) per second, at any given time. In the process to become stable, each atom discharges an electron (beta ray) in the half-million electron volt range.  This is an energetic particle.  Though likely attenuated while traveling through air, a particle will easily create ions which have the potential to disrupt DNA until it gives up all of its energy  while traveling through tissue.

Assuming the high end (10Bq of activity), we can expect an exposure of 2.014747 microsieverts/hr at a depth of 1 centimeter.  Presuming ingestion at constant exposures, I have this coming out to 1.75 rem/year.  As of April 5, PNRI numbers are only at 20 microBq, so it would be an interesting exercise to pay attention to future numbers and see if they validate the RIU simulation.

Edit:  Note the following Philstar article dated today, April 9th:

"Bernido said the amount of radiation elements coming from the earthquake-damaged Fukushima Daiichi nuclear power plant remained low as of last Wednesday. Detected were 47 micro-becquerels per cubic meter of iodine-131, 2.6 Bq/m3 of cesium-134, and 3.1 Bq/m3 of cesium-137. As of 9 a.m. yesterday, radiation level in the country remained normal at 100 to 115 nanosieverts per hour. Bernido said the PNRI would continue testing the radiation levels in the environment and products imported from Japan"

What gives?  Just a few days ago, PNRI readings for Cs-134 and Cs-137 were just 18 microBq/m3 (0.000018 Bq/m3) and 20 microBq (0.00002 Bq/m3) respectively.    This means that since April 5th, Cs-134 levels are 144,444 times higher, and Cs-137 levels are 155,000 times higher. But if this were the case, radiation readings would also increase beyond "100 to 115 nanosieverts per hour".

Day	Iodine-131 *(µBq/m3)	Cesium-134 (µBq/m3)	Cesium-137 (µBq/m3)
March 23	33	4.2	5.7
March 24	480	92	120
March 25	54	6.3	7.7
March 26	20	0.7	0.7
March 27	47	2.6	3.1
March 28	93	4.4	5.3
March 29	130	4.6	5.3
March 30	210	1.7	1.6
March 31	31	Not detected	0.7
April 1	57	4.3	5.7
April 2	61	9.9	12
April 3	160	86	100
April 4	79	53	79
April 5	51	18	20

These simulations out of RIU may be more accurate than i thought.  Philstar may also have printed their numbers wrong.  Will call the PNRI on Monday to clarify what's going on.