Bookmark and Share
Radiation from Japanese reactors has reached the United
States - The Facts
March 28, 2011
Colin Andrews
Thanks to Lindy Tucker (USA)
Xenon 133 radiation - source: WeatherOnLine
Carolinas utilities report radiation from Japan
                                                   March 28, 2011

RALEIGH, N.C. — Utilities in North and South Carolina are adding to the list of states in the U.S.
reporting trace amounts of radiation from a nuclear reactor in Japan that was damaged by an
earthquake and tsunami.

Progress Energy and Duke Energy in North Carolina and South Carolina Electric and Gas Co. all
operate nuclear plants and say they've detected trace amounts of radiation.

Nuclear experts and health officials say there's no public health risk. The U.S. Environmental
Protection Agency says people are exposed to much more radiation on an international airline flight.

Progress Energy says it picked up low levels of iodine-131, a radioactive byproduct of nuclear
fission, at its nuclear plant in South Carolina and a Florida plant.

Massachusetts, Nevada and other Western states also have reported minuscule amounts of

Source: Comcast

March 27, 2011

When and how was I-131 found in rainwater in Massachusetts?

I-131 was detected in a rainwater sample collected on March 22, 2011 at a routine monitoring station
in Boston. The Massachusetts Department of Public Health (DPH) participates in the USEPA
Radiation Network (RadNet) monitoring system. RadNet has about 180 sites across the US that
routinely monitor for radioactivity in the environment. Preliminary results were available by Thursday
evening, March 24th and confirmatory testing showed a level of 79 pCi/L of I-131.

Are these rainwater samples taken elsewhere in Massachusetts? If so, what have those results

The rainwater sample collection site in Boston is the only location in Massachusetts where such
samples are taken.

Can we expect to continue to see I-131 in rainwater samples in Massachusetts?

Until the Japan nuclear plant is stabilized, trace amounts of I-131 may continue to be detected as it
rains in Massachusetts. However, levels will remain significantly lower and not of any health concern.

Has I-131 been detected in any air samples in Massachusetts?

No. Air samples collected at the same monitoring location have not detected any amount of I-131.

Should I be concerned about I-131 in Massachusetts water supplies?

No. I-131 concentrations in rainwater are considerably higher than what might be detected in a
surface water body. Any I-131 deposited would be greatly diluted once it falls onto a water body. In
addition, DPH worked with MWRA last week to collect raw drinking water samples form the Quabbin
and Wachusett reservoirs as part of the commonwealth's expanded system of watchfulness in relation
to events in Japan. The results of both of those samples tested showed no detections of I-131.

How did I-131 show up in rainwater samples but not in air samples taken?

The I-131 found recently in rainwater is likely the result of atmospheric conditions. The trace amounts
of I-131 have been trapped in cloud formation and moved across the US as part of weather patterns.
Recent precipitation in Massachusetts deposited I-131 in sample collection containers.

Have other states detected I-131 in their rainwater and or the air?

Yes, the radioisotope has been found in many states. It was first detected in air and rainwater on the
west coast and these trace amounts of I -131 have moved east.

Will DPH be conducting more tests of air and water samples for I-131 or other radioisotopes ?

Yes. DPH will continue its monitoring efforts through the RadNet system. In addition DPH and the
state Department of Environmental Protection (DEP) will be taking representative samples of surface
water drinking water supplies across the state beginning today (March 27, 2011). Results of these
tests will be released as soon as they are available. Samples will be collected by DEP and sent to the
state Environmental Radiation Laboratory in Jamaica Plain. Due to the processing time and
laboratory capacity results will take 2-3 days for each set of samples collected (two each from each
area tested).

Will there be any testing of foods, such as milk?

As part of ongoing federal safety requirements, there is regular testing of milk and other selected
foods for radioactivity and other potential contaminants. The federal standard for I-131 in food is
4,600 picoCuries per kilogram of food product; for milk, this would be about 4,600 picoCuries per liter.
In initial testing, USEPA found no I-131 in milk products in the US, using a test that can detect as low
as 25 picoCuries per liter. This monitoring by the federal officials will continue in Massachusetts and
other states.

What is Iodine-131?

Iodine-131 (I-131) is a radioactive form of the element iodine, also referred to as radioiodine. I-131 is
in a class of radioisotopes called “beta emitters”. I-131 is a byproduct of nuclear energy production. It
is also used in medicine to diagnose and treat disorders of the thyroid gland.

Once detected, how long does I-131 remain in the environment?

I-131 has a short “half-life” of 8 days. This means that in 8 days, half of the original I-131 will have
decayed to a stable (non-radioactive) state. That level will be half again in 8 more days and so on.

How is the radioactivity of I-131 measured?

Radioactivity is measured in units called Curies. In small quantities, the radioactivity of I-131 is
measured in picoCuries. A picoCurie is one-trillionth of a Curie, or 0.000000000001of a curie. An
even smaller unit of radioactivity is a femtoCurie, which is one thousand times smaller than a

Radiation in the form of Iodine 131 has shown up in rainwater
in Massachusetts (USA East Coast)
Posted March 28, 2011
"Radioisotope has been found
in many states. It was first
detected in air and rainwater
on the west coast and these
trace amounts of I -131 have
moved east".
Once detected, how long
does I-131 remain in the