Sunday, May 13, 2012

Tritium in Swimming Pools


Capt. Clyde Stagner (Ret.) shared with me a letter he wrote to the Maricopa Association of Governments and the EPA

Capt. Stagner is very concerned about the lack of monitoring of tritium emitted from Palo Verde Nuclear Plant.

The only tritium monitoring in Phoenix is in drinking water.
[CORRECTION to original post: Apparently the EPA doesn't even do that: Clyde corrects me here: "ALTHOUGH THE EPA COULD MONITOR Phoenix 's drinking water for tritium,the EPA does not do so. This is frustrating because of the local airborne releases of tritium verified by the EPA's measurements of tritium in Phoenix 's precipitation. An EPA Rep stated That the EPA didn't have the funds to monitor Phoenix 's drinking water for tritium."]

There is no monitoring of it in our air or precipitation (or water!)

Unfortunately, tritium can contaminate both air and water.

I am going to include below some excerpts from Capt Stagner's analysis.

"Tritium is a radioactive contaminant with a half life of 12.32 years and emits a low energy beta particle. Tritium, emitted as a gas, combines with oxygen to form tritium oxide, or tritium water... Tritium cannot be removed through filtering."

Tritium can be absorbed through the skin (or inhaled or ingested).

MAJIA HERE: I am going to interject here a finding about body's absorption of tritium from a research article on internal emitters:

"low energy beta emissions from tritium (3H) decay have been shown to have RBE (ratio of the absorbed dose) values of up to between 2 and 3 (compared to gammay rays), for in vitro end-points including cell killing, mutation and induction of chromosomal aberrations" (p. 144)

Harrison, J., & Day, P. (2008). Radiation Doses and Risks from Internal Emitters. Journal of Radiological Protection, 28, 37-159.

MAJIA HERE: I'll provide some more sources for the unpleasant effects of tritium at the end of this post but now back to Capt. Stagner's letter:

[paraphrasing] Capt. Stagner notes that the EPA assessed tritium concentrations in Phoenix precipitation from March 1985 to December 2010. The EPA has since stopped collecting and analyzing tritium in Phoenix precipitation. 

The EPA HAS PROVIDED NO REASON FOR CEASING TO MONITOR TRITIUM IN PHOENIX PRECIPITATION.

Using EPA data from 2010, Capt Stagner extrapolated the probable tritium concentrations in Phoenix precipitation.

Using data about probable concentrations of tritium in precipitation, Capt. Stagner has calculated the probable concentration of tritium in swimming pools in the Phoenix area, based on the volume of water.

He writes: "Swimming 2 hours a day during a six  month swimming season results in a dose of .... 1.927 millirem. Swimming 2 hours a day annually results in a dose of 3.908 millirem."

He concludes: "The latter dose exceeds the ALARA OF 3 MILLIREM"

[ALARA stands for As Low as Reasonably Achievable and is a regulatory requirement. See http://www.ncsu.edu/ehs/radiation/forms/alara.pdf for background]

MAJIA HERE: The data above only concern exposure to tritium through swimming in pools. We spend a lot of time in swimming pools in Phoenix in the summer because it is so hot. Kids, especially, are in the pool a LOT during the summer.

However, swimming pools are not our only source for exposure to tritium.

It is clear that we inhale tritium in the humidity in Phoenix air (mostly late summer when it is very hot and relatively humid) and we no doubt ingest tritium through our food. 

Tritium can be absorbed by plants and Capt Stagner notes in a personal email to me that Phoenix reclaims water that may be contaminated with tritium. Also, tritium may contaminate sludge used on land (as fertilizer?)

Text of email from Capt. Stagner regarding tritium contamination of wastewater and sludge:
More than 90% of Phoenix wastewater is highly treated and reused for crops,power generation(utility), and turf irrigation(Ref:Phoenix Water and Wastewater Facts)
 Part of effluent from two major sewage treatment plants in the Phoenix area,both activated sludge plants with chlorination(Ref:FAO Corpoate Document Repository).
  
As of March 31,2004,ADEQ serves as the sewage sludge program and enforcement authority in Arizona. EPA maintains an oversight.Bisolids(Another name for sludge)Program is regulated under 18 AAC title 10. Persons using biosolids for land application must register with ADEQ.
AZ Dept of Health Services must approve and certify list of laboratories to test biosolids. Their application, Section C-Solid waste Methods,pages 33-41 includes the following listed under Radiochemistry Tests required are: Alpha emitting Radium, Gross Alpha and Beta,and Radium 228. 
Tritium is not listed: its beta particle is low energy. 
This application also lists Wastewater radiation tests of:Gross alpha,Gross Beta,Radium total,and radium 228-tritium is not listed.This license laboratory application also lists Drinking Water which includes tritium,Page 2
In researching utility radiation reports to NRC, a container of incoming treated water for cooling water was noted as contaminated with tritium. This memory observation needs to be verified before citation as recycled tritium is concluded
In addition,the 40 reservoirs of Phoenix Water require evaluation for possible tritium contamination.
The best-clyde 
MAJIA HERE: The upshot is that we in Phoenix are swimming in tritium and no doubt ingesting it through other means as well.

Tritium is nasty and its biological hazard from absorption is greater than comparable levels of exposure from gamma.
The EPA is not monitoring tritium in our precipitation, which contaminates our air, our pools, and, potentially, our agriculture.

Capt. Clyde Stagner's book, Hidden Tritium, can be found at Amazon.com
PREVIOUS POSTS ON CAPT STAGNER'S WORK


ADDITIONAL REFERENCES ON TRITIUM

Bridges, B. A. (2008). Effectiveness of tritium beta particles. Journal of Radiological Protection, 28, 1-3.

Fairlie, I. (2007) RBE and wg values for Auger emitters and low range beta emitters with particular reference to tritium. Journal of Radiological Protection, 27, 157-168.

Harrison, J. D. Khursheed, A., & Lambert, B. (2002). Uncertainties in dose coefficients for intakes of tritiated water and organically bound forms of tritium by members of the public. Radiation Protection Dosim. 98, 299-311.

Straume, T. (1993) Tritium Risk Assessment. Health Physics, 65, 673-682.

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