|COMMENTS TO THE DRAFT 2006 ICRP RECOMMENDATIONS.
Pan American Health Organization (PAHO)
Panel Presentation for the System of Radiological Protection; A Stakeholder Dialogue on the Draft 2006 Proposals, Washington D.C., United States, 28-29 August 2006
Prepared by Gerald Hanson and Pablo Jiménez
The Pan American Health Organization (PAHO)
The Pan American Health Organization (PAHO) is an international public health agency with more than 100 years of experience working to improve health and living standards of the people of the Americas. It enjoys international recognition as part of the United Nations system, serving as the Regional Office for the Americas of the World Health Organization, and as the health organization of the Inter-American System.
PAHO is based in Washington, D.C., and has scientific and technical experts at its headquarters, in its 27 country offices, and its nine scientific centers, all working with the countries of Latin America and the Caribbean in dealing with priority health issues. The health authorities of PAHO's Member States set PAHO's technical and administrative policies through its Governing Bodies. PAHO Member States include all 35 countries in the Americas; Puerto Rico is an Associate Member. France, the Kingdom of the Netherlands, and the United Kingdom of Great Britain and Northern Ireland are Participating States, and Portugal and Spain are Observer States.
PAHO was relieved to learn that the main numerical recommendations given in ICRP 60 remain valid (except the updating of the radiation and tissue weighting factors in the dosimetric quantity, effective dose) and that changes in government regulations based on previous ICRP recommendations will not be necessary. This is of the utmost importance to all PAHO Member States, which formally endorsed the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (BSS) at the XXIV Pan American Sanitary Conference in 1994. Currently all of the Member States have some form of specific requirements concerning ionizing radiation and all of them are stakeholders in the new ICRP recommendations through their responsibility for public health. However, regulatory authorities are non existent in some of them and others only have some limited legislation regarding the use of ionizing radiation. Consequently, every public health resource that would be used in the revision of the existing regulations would be lost to otherwise productive work such as the implementation of the current international requirements.
It was noted with satisfaction that the ICRP will maintain the three fundamental principles of justification, optimization, and dose limitation. Having noted the stakeholder’s comments on the 2005 ICRP draft recommendations, PAHO wishes to clearly state its belief that the justification principle should not be weakened or deemphasized, and that it has also been taken into account in the new Safety Fundamentals (to be published).
Our impression is that the treatment of justification in the Introduction, Section 1, of the June 2006 draft is adequate.
In Section 2, Aims and Scope, while cognizant of the Commission’s effort to democratize and to respect diverse societal considerations, PAHO believes that some uses of radiation are not justified in any society with which it is familiar. An example would be the indiscriminate use of whole body CT screening in unselected populations, such as at shopping malls or other commercial venues. The Commission is urged to reexamine the issue of uses of radiation that cannot be justified and, if ultimately it decides to shy away from making any declarations about certain uses, it is encouraged to provide an extensive discussion to assist those health, regulatory, or professional authorities that may need to make such declarations. Examples of areas in which guidance would be most helpful are: radiological examination for theft detection and for security reasons, drug smuggling, and for dangerous items carried by travelers.
In Section 6, Medical Exposure,, adequate space is allotted to the topic of justification, however, some specific paragraphs are questionable. See the comments below under Medical Exposure concerning paragraphs 249 and 269.
The fundamental principle of optimization (paragraph 11 of the June 2006 draft) is explained adequately throughout the draft and is, essentially, as now incorporated in the BSS. However the treatment of constraints is still confusing. This confusion may be due in part to the change in ICRP terminology from “upper bounds” to “dose constraints” (paragraph 199) as well as to the English language. If the definition of fundamental is accepted as: “basic, underlying, original or primary source”; perhaps the word, fundamental, should be limited to the three primary principles of justification, optimization, and dose limitation. If “worth having or, pleasing excellent or fine” could be associated with dose constraints; then dose constraints would be “desirable” . This would be a significant step to alleviate the confusion because “desirable” fits the description of dose constraints in paragraphs 11, 184, 198, 200, 209 and most (if not all) other situations in the draft; and is the way constraints are used in the BSS and is generally understood. Otherwise, “dose constraints’ may be interpreted by some regulatory authorities as “limits” with the legal consequences that this may imply.
Regarding terminology (paragraphs 29, 49) PAHO commends the wise decision to resolve the controversy in terminology concerning “tissue reactions” and “deterministic effects” by using the “also called” compromise and mentioning both generic and descriptive terms, as appropriate. This also applies to “stochastic effects” and “cancer or hereditary effects”. It would be a terrible waste of resources if some countries were forced to make changes in regulations only because ICRP used new terms.
Regarding paragraph 177 (Section 5.5 The exposure of women), the last sentence: “The working conditions of a pregnant worker, after declaration of pregnancy, should be such as to make it unlikely that the additional dose to the fetus would exceed about 1 mSv during the remainder of the pregnancy” adds no precision nor additional protection level to what has already been said in the same paragraph and should be eliminated. What was already properly indicated in a previous sentence, i.e. “It is the Commission’s policy that the methods of protection at work for women who are or may be pregnant should provide a level of protection for the fetus broadly comparable to that provided for members of the general public” is in accord with the BSS and has been accepted by the stakeholders. In fact, a limit of 1 mSv during the remainder of the pregnancy is a higher limit for the protection of the public, and consequently the fetus will be less protected than any member of the public.
There are two additional important comments regarding terminology. The first one is the term “operator” that is used throughout the document when in most of the cases (if not in all of them) the Commission would mean “user”. This should be changed in order to avoid confusion in the medical field. The other one is the term “radiation worker” in paragraphs 167 and 170, which is not adequate and should be avoided as it could be misleading. "Workers engaged in radiation work" is preferred by the International Labour Organisation (ILO), whose terminology in the occupational health area should be accepted.
With respect to radon, more clarification regarding constraint and action level is needed since in some parts seems to be interchangeable.
Unfortunately, this Meeting (28-29 August 2006) and the deadline for sending these comments to the ICRP seems to be early to have a full and meaningful discussion of medical exposure when so much of the draft is dependent upon a forthcoming report of ICRP Committee 3. Nevertheless, PAHO will try to provide constructive comments. One general comment concerning the entire section is that there is a lot of uncalled for, and superfluous, text that should be eliminated. Specific comments are provided as follow.
Regarding paragraph 243, the second sentence should say: “Except in radiotherapy and therapeutic nuclear medicine,…..etc.”
Regarding Section 6.1 (and earlier in Section 5.7), justification is fundamental. Various stakeholders including the medical profession should be involved. These stakeholders, perhaps in excessive deference to professional bodies, are treated as unimportant. We are leery of the ICRP statements in paragraphs 191 and 249. These tend to disparage the role of government, including national and local health authorities and regulatory authorities and some state-supported universities. Our concern reminds us of statements heard from the profession 30 or 40 years ago, i.e. “medical radiation is safe”, period. Despite the confusion between paragraphs 191 and 249 about the levels of justification concerning the medical use of radiation, there are uses for which the health authorities have had (and in similar future situations would continue to have) a leading role with respect to either the regulatory authorities or the professional bodies. For example in the surveys of unselected populations as well, as certain selected populations for diseases such as tuberculosis and breast cancer; routine chest radiographs on admission to hospital, and before and after surgery, chest fluoroscopy, and obstetric radiography. Consequently, the health authorities have an important role to play in the medical exposure of the patients.
The BSS, which is mentioned in paragraph 10, treats justification in a quite acceptable manner. It would be counterproductive if this treatment had to be revised because of the new ICRP recommendations. For example concerning medical exposures, the BSS (Appendix II, paragraph 5 says: “In justifying each type of diagnostic examination by radiography, fluoroscopy or nuclear medicine, relevant guidelines will be taken into account, such as those established by the WHO”.
Regarding optimization, the important message (paragraph 253) from ICRP that optimization is applicable, regardless of the type of source or terminology used is praiseworthy. This is clear and straightforward.
The general guidance concerning optimization in Section 6.2, paragraphs 251-253, is satisfactory and does not preclude more detailed guidance provided in the BSS and other publications.
Specifically, regarding diagnostic reference levels in Section 6.2.1, paragraph 254, the choice of wording indicates that more editing effort is needed or, more seriously, that a reality check is in order and the Commission should re-consider how this data is generated. In the sixth sentence “adopted” is more accurate than “selected”. The values in the literature (available for adoption) have usually been determined (selected) by groups other than the professional medical bodies i.e. the health authorities or the regulatory authorities. If “selected” is exactly what ICRP means, the comments made above concerning justification and the unimportance of other stakeholders are also relevant.
Another specific comment concerns the last sentence. The following would be more realistic, and would avoid ICRP mandating something that will not be possible for some time into the future: “Ideally, the adopted values will be specific to a country or region”. Many countries do not have the resources to undertake the studies necessary to produce and revise their own reference levels, or “guidance levels”, as they are called in the BSS. The BSS recognized this with the following statement (Appendix II, paragraph 25): “In the absence of wide scale surveys, performance of diagnostic radiography and fluoroscopy equipment and of nuclear medicine equipment should be assessed on the basis of comparison with the guidance levels specified in Schedule III, Tables III-I to III-V. These levels should not be regarded as a guide for ensuring optimum performance in all cases, as they are appropriate only for typical adult patients and, therefore, in applying the values in practice, account should be taken of body size and age”.
Regarding paragraph 255, the sentence should read: “Diagnostic reference levels are….etc.”
Regarding exposure of pregnant patients in Section 6.3, paragraph 262, the first sentence should be: “It is imperative to ascertain whether a female patient is pregnant prior to radiotherapy.
Regarding Sections 6.4 and 6.5 there appears to be confusion in the draft ICRP recommendations resulting from two contradictory ICRP reports.
Specifically regarding paragraphs 265, 266, and 275: assuming the duplication between 265 and 266 will be treated as a typographical error, PAHO supports the general guidance in the resulting paragraph 266. However regarding paragraph 275, PAHO does not believe a dose limit should be established for infants, young children and casual visitors. What regulatory authority would want to (or dare) go into an anguished family’s home to enforce this dose limit? Dose limits can be used around nuclear facilities, but not in private bedrooms. The values should be left as constraints, that is to say, desirable to achieve, but not legally enforceable. In addition, with regard to the actual values used for the recommended constraint, PAHO does not believe there is any need to change the numbers from those given in the BSS. These are 5mSv for comforters or visitors (including casual visitors) and 1mSv for children (including infants). Many countries, worldwide, are following the BSS. There is no valid reason for requiring a change in the BSS to revise a constraint from 5mSv to “a few mSv” or to alter the 1mSv constraint to a 1 mSv dose limit. Attention is called to ICRP’s statements in the Introduction Section and its intention not to require changes to appropriately-based regulations. The stakeholders trust that ICRP means what it has said and have faith that they will not be disillusioned.
Regarding Section 6.4.2, medico-legal exposures, and paragraph 269, this is strange since “medico-legal” is not discussed nor defined in the text and insurance companies are the only subject matter. It would be very useful if ICRP would include this term, which is not well-defined and is usually associated with medical malpractice or claims resulting from accidental injuries due to negligence, in the glossary. In addition, PAHO does not understand nor agree with the new concession given to insurance companies. These insurance examinations might better be called commercial-legal or risk management-legal rather than medico-legal. The BSS (Appendix II, paragraph 1) says: “Registrants and licensees shall ensure that: (a) no patient be administered a diagnostic or therapeutic medical exposure unless the exposure is prescribed by a medical practitioner;…..”
The BSS, (Appendix II, paragraph 6) under “Justification of Medical Exposures” also says: “Any radiological examination for occupational, legal or health insurance purposes undertaken without reference to clinical indications is deemed to be not justified unless it is expected to provide useful information on the health of the individual examined or unless the specific type of examination is justified by those requesting it in consultation with relevant professional bodies.”
Even if the insurance company arranges for a medical practitioner to prescribe the examination, there are reasons to believe that all such examinations are not voluntary nor are they always for the benefit of the individual. A certain amount of coercion is involved. If the individual refuses, he may not get the insurance clearance, or policy he is seeking. In fact, instead of obtaining the insurance policy, based on his existing situation and medical records, he may be excluded from the insurance coverage as a result of the radiological examination.
In addition, the “higher values” mentioned are for constraints for medical exposure, while dose limits for public exposure would be more appropriate. What kind of risk-benefit balance can equate a few mSv per episode for an insurance examination with the few mSv (5mSv according to the BSS) for comforters of sick patients?
Furthermore, with regard to all “medico-legal” exposures, and especially those required by insurance companies, serious consideration should be given to placing these in the category of public exposure, along with exposure for theft-detection and security reasons, drug smuggling and screening of travelers for dangerous items. The fundamental principles of justification, optimization and dose limits should then be applied to all of these non-medical exposure situations. An example showing how the BSS has treated theft detection is in its Appendix II, paragraph 9: “Radiological examinations for theft detection purposes are deemed to be not justified; should they nonetheless be conducted, they shall not be considered medical exposure but shall be subject to the requirements for occupational and public exposure of the Standards.”
Regarding Section 6.5, release of patients after therapy with unsealed radionuclides, the confusion mentioned above between constraints and dose limits is most evident.
Specifically in paragraph 271, after waste is discharged from a nuclear medicine department and off the premises, it should be subject to dose limits, and not only to constraints. Also not only thyroid cancer is relevant, so those words should be deleted.
Specifically regarding paragraph 272, confusion is caused because the public, for whom doses my need to be limited (Public exposure) is mixed with relatives whose doses may need to be constrained (Medical exposure).
Specifically regarding paragraph 275, as mentioned above PAHO believes that exposure of these persons; infants and children (if family members) and casual visitors should be treated as medical exposure, subject to constraints and not as public exposure subject to dose limits. We believe the BSS does it right and it should not be changed.
Implementation of the Commission’s Recommendations
Regarding Section 11, paragraph 359 is not complete and more research by ICRP would be in order. For example, PAHO and WHO, through its six Regional Offices, provide advice to their member states. An important example is the PAHO publication (1997) “Organization, Development, Quality Assurance and Radiation Protection in Radiology Services: Imaging and Radiation Therapy”.
Regarding Section 11.2.1, occupational services for protection of health, paragraph 386; the last sentence includes a rather weak and almost cryptic statement that has appeared in ICRP recommendations for some time, thus leaving the subject open to argument and advocacy. This statement is: “Furthermore, the radiation component of the working environment should have no influence on the administrative conditions of service of those occupationally exposed.” During preparation of the BSS extensive discussion by many stakeholders resulted in clarification of this choice of wording. The stakeholders agreed upon the following wording (Appendix I paragraph 15) “The conditions of service of workers shall be independent of the existence or the possibility of occupational exposure. Special compensatory arrangements or preferential treatment with respect to salary or special insurance coverage, working hours, length of vacation, additional holidays or retirement benefits shall neither be granted nor be used as substitutes for the provision of proper protection and safety measures to ensure compliance with the requirements of the Standards.”
If ICRP is in agreement with the existing BSS provision, it is urged to say so forcefully and with enough detail and clarity so as to avoid re-visiting this subject with the myriad of discussions that would be entailed. Even now many physicians and other medical personnel are following ICRP recommendations (dating from the 1930s and 1940s) to justify special compensation or treatment; this practice is diverting scarce resources that should be used for patient care.
In our comments we have referenced and quoted the BSS. While realizing that improvements can be made, we believe it is worth mentioning that some 20 meetings were held during preparation of the BSS over a three-year period and that hundreds of experts throughout the world were involved. The final wording is a result of numerous deliberations that resulted in agreement between the six Sponsoring Organizations and adoption by their Member States.