Nuclear “Effective Dose” Radiation: ICRP vs. US EPA

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Effective Dose, EPA, EPA comment, ICRP, ICRP recommendations, morbidity, mortality, nuclear industry, nuclear regulation, organ exposure, radiation exposure, radiation standards, thyroid and radiation, thyroid disease, thyroid exposure, US EPA

As made clear in the diagram and article below, in the ICRP, and even the NRC law, “Effective Dose” is about risk to various parts of the body, cause by ionizing radiation. “Protection dose” is a misnomer. It is not an annual dose limit, as some appear to think. Frighteningly, this appears to include an EPA “expert” (one can hope now retired).

Diagram by Doug Sim, CC-By-SA-3.0 via Wikipedia, Red added to emphasize additive nature

As is clear in the above diagram, apparently done by a radiation standards-calibration expert, and the Wikipedia article below, bodily parts are additive, in this model. It is also supposed to be in the ICRP recommendations (though they seem to violate it for skin and eyes). So, you can’t have one organ having a higher amount of radiation exposure than the entire body, in this model. This is also logic. And, why would you want an organ, such as your thyroid, which even the governments-nuclear industry recognize as especially sensitive by giving out potassium iodide, to have more exposure than the entire body? And yet, the US EPA has this in their current “standard”, now up for possible change. The EPA allows 75 mrem (0.75 mSv) to the thyroid and 25 mrem (0.25 mSv) to other organs and 25 mrem (0.25 mSv) to the entire body. This is for a member of the public who is offsite and who has nothing at all to do with the nuclear industry! This is above and beyond “background”, which now includes historic nuclear emissions – meaning the more the nuclear industry pollutes, the higher the world average background goes, and the more they can pollute, while saying that the emit almost nothing compared to background!

In their request for comment (deadline Sunday), the EPA also strangely wonders if morbidity (illness) should be counted as part of risk or only mortality (death). It is clear that morbidity whether from cancer, or other radiation induced illness, matters; it should be counted; illness is generally a greater burden upon the individual and society. than death. This is the easiest of the questions which the EPA asked in their request for comment, probably the most important, but the most overlooked in responses. For instance, everyone agrees that radioactive iodine can cause thyroid disease or cancer, which requires the taking of medication for life and without the medication you die. But, if morbidity is not counted, thyroid-induced disease and non-fatal thyroid cancer won’t be counted. If someone dies from lack of thyroid medication, it surely won’t be counted. Non-domesticated animals don’t get thyroid medication, and they won’t be counted anyway.

It is critical to note that where there are long-lived radionuclides involved, as in the nuclear industry (in contrast to medicine), the maximum annual exposure for the entire body or organs added together, according to the ICRP, is 10 mrem (0.10 mSv), which while lower than the EPA’s 25 mrem (0.25 mSv) and the NRC’s 100 mrem (1 mSv), appears still too high and even unnecessarily so by nuclear industry standards. Even the nuclear industry claims to do significantly better, which should make everyone wonder the game-plan of the US EPA and NRC, which provide them with a huge possibility of polluting even more, whereas they seem currently to pollute more than nuclear facilities in some other countries (based on the few we have looked at in the US and Germany). In a similar vein, Canada allows 7,000 Bq/liter of tritium in their water, whereas the Canadian nuclear industry are reportedly fine with a proposed 20 Bq/liter (Ontario), since they claim to emit 18 Bq/liter, even though Canadian CANDU reactors produce much more tritium than US types. The US EPA has no water standard for nuclear emissions and the EPA “Clean Water” drinking water standard allows up to 740 Bq/liter of tritium, if there are no other Beta emitters (and if they even test for all beta emitters).  A becquerel (Bq) is one radioactive disintegration (emission) per second.  Your average drinking water-cola bottle is about 1/2 liter, and so this 740 Bq would be 370 radioactive emissions per second in your little bottle of water or cola – does that sound like clean water? The European Standard is 100 Bq per liter for tritium, which is still too high: 50 radioactive emissions in your small water or cola and 150 in your large, 1 1/2 liter bottle.

Where is EPA consideration of Effective dose to plants, animals and non-human life? Isn’t the EPA the Environmental Protection Agency? Animals are used as radiation sentinels, with good reason!

As long as there is nuclear power, and if nuclear waste is not properly watched and managed, thyroid disease will be an increasing problem for humans (and many animals). It is not an “annual” dose limit or “annual” estimate of harm, which will really help with long-lived radioisotopes, such as Iodine 129 (129I), half-life 15.6 million years. As remarked by Landis et. al. (2012) “The focusing and concentrating of radioiodine fallout on a landscape carries some implication for human 131I exposure, though this risk is mitigated by the brevity of the 131I half-life… More important are implications for 129I (half-life 15.6 Ma), which has a fission yield approximately one third that of 131I, and which, due to its long half-life and continued release from ongoing nuclear energy production, is perpetually accumulating in the environment and poses a growing radiological risk.” (Emphasis added; Landis et al.,”Surficial redistribution of fallout 131 iodine in a small temperate catchment“, PNAS, March 13, 2012, vol. 109, no. 11, p. 4067. Entire article available for free here: http://www.pnas.org/content/early/2012/02/28/1118665109.full.pdf)

Our commentary continues after the Wikipedia article. Highlights were added by us. Those who prefer to read the unhighlighted online version, need to check the last date updated, to make sure that the nuclear lobbyists have not changed it. The nuclear industry appears to have people working full-time to manipulate Wikipedia now, which must be born in mind, when reading their articles.







In “external links” to this wikipedia article, there is a link to an article by Boyd, who works or worked for the EPA, where he seems to allege that the EPA thyroid exposure of 75 mrem (.75 mSv) is more protective than the EPA body exposure of 25 mrem (0.25 mSv). The other organs are only allowed 25 mrem (0.25 mSv), by the EPA.

While we hate to criticize Boyd, because he looks like a nice jolly fellow, someone’s got to do it: Boyd’s argument goes against logic in general and appears to go against the “Effective Dose” concept, as explained by the ICRP, the Wikipedia article and the NRC (as understood by us). Excepting, of course, if only the thyroid were directly irradiated by 0.75 mSv (75 mrem), the distant parts of body could possibly get less radiation than if the entire body were irradiated at 0.25 mSv (25 mrem). But, that seems largely a medical issue, not an EPA issue. Or, if radio-iodine, which settles predominantly in the thyroid were given internally by a doctor or if it were the only nuclear emission (which it is not), then the body would get less than the thyroid.

Nonetheless, even in these scenarios, 25 mrem (0.25 mSv) to the thyroid would be less than 75 mrem (0.75 mSv). To say otherwise goes against the whole problem of ionizing radiation where higher amounts can actually lead to almost instant death. Ionizing radiation is not an all you can eat buffet – more is not better! Knowing that a higher dose is more dangerous is the whole basis of radiation protection.

Following the “Effective dose” concept, with 25 mrem (0.25 mSv) body exposure the thyroid would theoretically get a 1 mrem (0.01 mSv) dose, i.e. 4% of the dose. Furthermore, if theoretical exposure to the thyroid were 75 mrem (0.75 mSv), then the entire body dose would have been 1875 mrem (18.75 mSv), i.e. 4% to thyroid and 96% to the rest. A dose exposure of 75 mrem (0.75 mSv) to the thyroid, counts as a total dose of 75 mrem. There’s just no way to turn 75 mrem into more protection than 25 mrem, outside of an upside down Orwellian world, where war is peace and love is hate.

Radionuclides such as radio-iodine, which target mostly the thyroid (except in pregnant and lactating women where it settles in the breasts and breast milk), do indeed show that this model is not worth much outside of calculating theoretical risk of gamma or x-ray exposure to nuclear workers and in radiology. However, this is not a reason to suggest that the thyroid get a higher rate of exposure. On the contrary. Even the NRC seems to allow “only” 10 mrem (0.10 mSv) to the thyroid. While this last is based on their outrageously high exposure level of 100 mrem (1 mSv) it is still more thyroid protective than the EPA – 0.1 mSv is more protective than 0.75 mSv, (unless someone is manipulating the meaning of mSv with changes in weighting factors, etc).

Frighteningly, it appears that Boyd is treating the “Effective Dose” as a protective amount, whereas it is a measure of distribution of potential risk-detriment, as explained in the Wikipedia article, and by the NRC:
NRCs regulations, Title 10, Chapter I, of the Code of Federal Regulations PART 20—STANDARDS FOR PROTECTION AGAINST RADIATION
§ 20.1003 Definitions“.
“Weighting factor WT, for an organ or tissue (T) is the proportion of the risk of stochastic effects resulting from irradiation of that organ or tissue to the total risk of stochastic effects when the whole body is irradiated uniformly. For calculating the effective dose equivalent, the values of WT are:”

The Logic used in criticizing Boyd: There has been much ado, and justifiably so, about the fact that the “protection” (actually detriment value) given to the gonads has been reduced. The 2007 ICRP rules only consider damage to the 2nd generation, whereas recessive mutations, induced by radiation, can appear much later, as has been known since at least 1927 with publication of Hermann Muller’s experiments. But, it’s not really protection that has been reduced but rather judgement of hazard or danger. While this is shocking, it is also kind of difficult to choose between brains or other needed body parts and offspring, when the model is unity. The model is clearly not protective doses or it would not have to add to one (100%).

In the “Effective dose” concept, as in General Medicine, the body is unity or a whole (many medical specialists also miss this point). Thus, estimated detriment or risk adds up to one or unity. So, if the body is 100%, as we see above, the estimated potential harm to the gonads has declined from 20% (1991) to 8% (2007). As can be seen, as well, the estimated harm to the thyroid has declined from 5% to 4% in the same period.

Therefore, if the body exposure were 25 mrem (0.25mSv), then 4% of that exposure is to the thyroid and that would be 1 mrem (0.01 mSv). If exposure to the thyroid is 75 mrem and it is only 4% of the entire body, then the exposure to the entire body would actually be 4/100 = 75/x or 4x = 7500, and x = 1875 mrem (18.75 mSv). If the thyroid were the only organ irradiated, the entire detriment to the body would seem still to be considered as 75 mrem (0.75 mSv). So, it appears that Mr. Boyd is either intentionally or unintentionally misleading people by claiming that 75 mrem (0.75 mSv) is more protective. Although he issues a disclaimer that his views were not necessarily those of the EPA, he has spoken and written in that article and others with EPA by his name.

If the decline in theoretical detriment to the gonads had not been so clearly spelled out by the ICRP 103 (2007), p. 190, then it would be easy to fall prey to believing that the levels were protection levels, as Mr. Boyd apparently has done, as opposed to levels of estimated harm. In his interpretation of the system, the decline in estimated harm would actually lead to more protection, and increase in estimated harm would lead to less protection, which is why we have said elsewhere that the entire system has been turned on its head, by him (i.e. the EPA, as long as he works there and announces affiliation with the EPA). While he has issued a disclaimer that his opinions are not necessarily those of the EPA, he should not be speaking with EPA beside his name, if he speaks on his own – nor should the US EPA let him. Or, he speaks for the government, or as a private citizen. It is clear that he has been asked to speak in various places because of his EPA affiliation.

If this model were dose limit rather than about theoretical harm, and if you took the outrageously high 1 mSv exposure rate suggested by the NRC for the general public (recall that this is above and beyond “background” and medical exposure and that now “background” includes Fukushima and Chernobyl and weapons plants and all previous nuclear emissions, whether by accident or on purpose), then the 1991 recommendation would give a radiation dose limit of 0.2 mSv compared to the 2007 recommendation of 0.08 mSv. If this were dose limit, as Boyd seems to think, then the 2007 recommendations would offer more protection to the gonads, since 0.08 mSv is less exposure than 0.2 mSv, whereas the ICRP says that the gonads are being offered less protection. So, following Boyd’s logic, the higher the dose you get, the more protected you are! This is a frightening position for an EPA regulator to take, and seemingly how he arrived at the frightening notion that a dose of 0.75 mSv offers more protection to the thyroid than a dose of 0.25 mSv. Unless Boyd is doing this intentionally, the blame largely falls on the ICRP for calling a risk model, a protection model. The blame also falls upon the ICRP for historically proposing a dangerous dose limit of 1 mSv, and the NRC for maintaining the 1 mSv. The ICRP has decreased the recommendation, when the emissions are of long-lived radionuclides, from 1 mSv to 0.1 mSv.

As even suggested in the NRC regulation, the “Effective dose” appears only really useful for radiation workers or full-body gamma or x-ray exposures. It’s utility appears questionable for ingested emitters which target specific organs, and alpha. It is also dangerous to assume annual exposure from radionuclides which stay in the environment, and sometimes in the body, for greater than a lifetime – even a true lifetime and not the shortened one which these people put into their calculations. A weighting factor of 20 appears to account insufficiently for dangerous alpha emitters which stay in the body for a lifetime – even lifetimes as unfairly short as those used in most of these calculations.

The ICRP mixes medical radiology and the nuclear industry together in a strange, inappropriate way. Radiology deals with x-rays and extremely short-lived radioisotopes, where the nuclear industry deals with some short-lived ones, but more importantly those, which accumulate in the environment for hundreds, thousands, and even millions of years. Although ingestion of radionuclides, in radiology, constitutes some risk to the entourage and the environment, it is supposed to have some medical benefit to the individual. No such argument can be legitimately made for the nuclear industry. Although we oppose the use of ionizing radiation in radiology, where it can be avoided, it is still a totally different thing from the nuclear industry and the standards should not be lumped together. The only thing which the two have in common is that even the smallest, short-lived radionuclide poses some risk. See for instance:
“Diagnostic treatment involving technetium-99m will result in radiation exposure to technicians, patients, and passers-by. Typical quantities of technetium administered for immunoscintigraphy tests, such as SPECT tests, range from 400 to 1,100 MBq (11 to 30 mCi) (millicurie or mCi; and Mega-Becquerel or MBq) for adults. These doses result in radiation exposures to the patient around 10 mSv (1000 mrem), the equivalent of about 500 chest X-ray exposures. This level of radiation exposure carries a 1 in 1000 lifetime risk of developing a solid cancer or leukemia in the patient. The risk is higher in younger patients, and lower in older ones. Unlike a chest x-ray, the radiation source is inside the patient and will be carried around for a few days, exposing others to second-hand radiation. A spouse who stays constantly by the side of the patient through this time might receive one thousandth of patient’s radiation dose this way.” http://en.wikipedia.org/wiki/Technetium-99m

Exposure due to radiation from nuclear power is totally unnecessary and exposure to radiation from medicine is largely unnecessary, with MRIs and ultrasound and even newer technologies. Radiologists could stay in business with these technologies – why they continue to promote the more dangerous ones based on ionizing radiation is unethical, immoral, and unfathomable. Ionizing radiation for medicine is 19th century Victorian and, unlike Victorian furniture, should have little place in the modern world. So, perhaps being dinosaurs defending their territory binds these two unlikely groups together within the ICRP, along with dangerous ionizing radiation. The ICRP radiation model is mostly academic in nature and of little use to those who are not nuclear workers. Worse, as many others have noted, it seems to be misused as a dose limit, whereas it is a model to express risk.

Remember to get your comment in before midnight Sunday! Any comment to say that the EPA needs to be more protective of people and the environment, etc. will be helpful. They may also be checking to see if anyone is watching their moves! It is a chance to let them know you are watching. Comments may be anonymous and most are, though those with the courage to sign their names (or pseudonyms) will probably be taken more seriously. There are signed comments from the Philippines, Canada, Germany and the US. http://www.regulations.gov/#!submitComment;D=EPA-HQ-OAR-2013-0689-0001
Other people’s comments and docket http://www.regulations.gov/#!docketDetail;D=EPA-HQ-OAR-2013-0689
NRC comments are coming up for November.

Japan reportedly aspires to get contamination down to 1 mSv above background, in some of the areas contaminated by Fukushima – which shows just how outrageous forcing people to be exposed to 1 mSv during normal operations of nuclear power plants is! “The aim is to get annual exposure from the contaminated environment down to 1 millisievert (mSv) above background. The most contaminated area where radiation doses are greater than 50 mSv/year must remain off limits, but some areas that are currently less than 5 mSv/year may be decontaminated allowing 22,000 residents to return.” http://en.wikipedia.org/wiki/Caesium-137 And, of course, whatever radiation is “cleaned” has to go somewhere too. Watch out everyone!

Postscript: The above post is based on our understanding of the ICRP 1990 and 2007 rules, the Wikipedia article and logic – what used to be called “common sense” and might need to be renamed “uncommon sense”.

We are no longer able to take comments, meaning we cannot take corrections either. So, we apologize for any errors, which you may find here or in any of our posts. We do not, however, apologize for differences in opinion, and chances are good that we have thought and read about this more than you have. Any true mistakes are most likely due to a combo of haste and lack of sleep. Chances are excellent that we also have a much higher level of education (combined or singularly) than you do, though formal education in the contemporary world tends to do more harm than good, we have multi-generational educations. Unlike the nuclear lobby-hacks, we lack an army of paid workers who might debate you or answer your queries. We are sorely understaffed and are volunteers. We have more information than we have time to post, as it is. The US EPA pays its workers well, compared to the average US worker, and the US Federal government gives excellent retirement and other benefits. They need to get to work for the taxpayer. It is the taxpayer who pays their salaries. If they prove themselves worse than useless, then the EPA will be easily shut down, and they will be unemployed and learn what work and hardship are. The ICRP rules are unfairly pricey, but the EPA should have access to the rules for free to them (taxpayer pays).

The top diagram is by Doug Sim, who is probably the same Doug Sim who calibrates nuclear equipment and teaches classes in Maryland (probably DC area). His classes are only $150, and could be worth considering for those interested in the topic, who are in the area. Maybe the EPA and NRC should attend? We wish we could go.

Here is an unhighlighted copy of his diagram. It could come in handy:

Diagram by Doug Sim, CC-By-SA-3.0 via Wikipedia