Tuesday, January 25, 2011

The Truth About Tritium: A Guest Post By Thomas Curphey

This letter appeared in the Valley News (my local newspaper) on January 19 2011. I have never met Thomas Curphey, but I phoned him when I read the letter. He graciously allowed me to use his letter as a guest post in my blog.

The Truth About Tritium

To the Editor:

A Valley News editorial some time ago decried the rise of "truthiness," the attitude that facts matter not at all and that perception is everything. The editorial closed by saying, "History is full of frightening examples of what can happen when individuals and political factions come to believe they are entitled to their own facts. Let's not go there."

In light of these noble sentiments, it is unfortunate that the Valley News continues to publish articles misrepresenting the risk of exposure to the radioactive element tritium. For example, on Jan. 12, the Valley News published an Associated Press article ("Hearing on Vt. Yankee Leaks") stating that tritium "is a carcinogen when ingested in high amounts." This statement is a particularly slippery example of "truthiness," one designed to play on our fears of radioactivity and cancer.

How has tritium been linked to cancer? In none of the ways that the reader is likely (and perhaps intended) to assume. As pointed out in previous letters to the editor, there is no documented case where a human has ingested large amounts of tritium and has subsequently developed cancer. Results of animal studies have been ambiguous. There are no statistical studies linking tritium exposure to cancer. In fact, the so-called link between tritium and cancer is purely hypothetical: because tritium is radioactive and exposure to radiation can lead to cancer, therefore, exposure to tritium leads to cancer.

Perhaps to cover up a paucity of actual facts and to lend credibility, the qualifiers "ingested in high amounts" are added. Why? Because the radiation emitted by tritium is of such low energy that it cannot penetrate human skin or even a piece of paper. Therefore, to have any chance of causing cancer, tritium, would have to be ingested in large amounts.

A balanced assessment by the California EPA of the health risks from tritium may be found on the Web at
I urge readers interested in learning the facts about this issue to read this document.

Apparently, for the Valley News, some people, in this case environmentalists opposed to Vermont Yankee, are entitled to their own facts.

Thomas J. Curphey

The writer is a retired research professor of pathology at Dartmouth Medical School and a retired adjunct professor of chemistry at Dartmouth College.


Joffan said...

The other important point is that the total amount of tritium released in the seep from the AOG system at Vermont Yankee would not qualify as "large amounts" even if collected together. It simply wasn't a significant incident, and was only ever an on-site monitoring and maintenance issue.

Still, BOO, radiation! Ha ha, scared you. Can I be governor now?

Meredith Angwin said...

Joffan. You are right. They have pumped thousands of gallons of water for disposal. If you put all that water together, it would contain 1 curie of tritium. Howard Shaffer ordered and received an exit sign on Amazon. A small one, containing 7 curies of tritium. It's an amazing show-and-tell device: Here it is folks! 7 trillion picocuries of tritium! I'm holding it in my hand!

Finrod said...

Off Topic:

Meredith, I've fallen into a debate with an anti-VY activist on the following site, but I believe your familiarity with the issue would go down better than my fleeting forays into the issue.


Meredith Angwin said...

Finrod. Going to Montpelier today and was in Brattleboro yesterday. It gets a little difficult keeping up. Thank you for telling me about this and thank you for challenging the endless junk about tritium! Wow, what a great comment thread on that post! Thank you for telling me about it. Can't do anything about it for a few hours.

Anonymous said...


You are correct in that Tritium in not much worse than smoking a few butts a day. The real problem with VY is that the buried pipes have severe cancer and continue to rot away.
Chemically, the tritium in and exit sigh is quite different from that found in the groundwater at VY. The exit signs, I believe are a gaseous form of tritium but I could be wrong.

Meredith Angwin said...


You are correct that the exit signs contain gaseous tritium. So you would breathe it in rather than drink it.

On the other hand, tritium in the groundwater is not the equivalent of "a few butts." It is the equivalent of eating a small portion of a banana. Or some kale. These foods contain a form of potassium which is also a beta-emitter. And no detectable tritium has ever been found off-site.

Your statement of the pipes "having cancer" is a very poor analogy. Pipes can be replaced when they wear out. Jeff Schmidt had an excellent guest post on misleading analogies on this blog.


I live in a house built in 1883. The house is almost 130 years old. The plumbing works quite well. Pipes in power plants can also be replaced and upgraded. I encourage you to read Jeff's post.

Mike Mulligan said...

My question is, say you put a pipe into the ground and pumped tritium down say 30 feet at the VY site at whatever it takes. Say you had 2 years. Through environmental dose models and typical pathways, how much tritium would it take to exceed the first NRC public dose limits without taking any action what so ever? Estimate how much tritium pumped into the ground it would take for the first off site person to get his legal limit exceeded.

I just made gibberish out of the NRC dose limits for nuclear plants...

My guess it would be gigantic...

Meredith Angwin said...

Mike. I don't think you made gibberish of anything. Limits on tritium in drinking water are set by the national EPA, and California has more stringent limits. You can see how California set its limits by following the link in this post. The limits are set by health effects, not the amount released or not-released by any source.