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Radioactivity in the environment chapter 8 ethics in practice—protecting workers Radioactivity in the environment chapter 8 ethics in practice—protecting workers Radioactivity in the environment chapter 8 ethics in practice—protecting workers Radioactivity in the environment chapter 8 ethics in practice—protecting workers Radioactivity in the environment chapter 8 ethics in practice—protecting workers

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Radioactivity in the Environment, Volume 19

ISSN 1569-4860, http://dx.doi.org/10.1016/B978-0-08-045015-5.00008-3

Ethics in Practice—Protecting

Workers

Christopher J Kalman

Occupational Health, Morelands, Astley Ainslie Hospital, Grange Loan, Edinburgh, UK

E-mail: Chris.Kalman@nhslothian.scot.nhs.uk

Chapter Outline

8.1 Introduction 131

8.2 Radiation Protection in

8.3 Ethical Requirements for

Occupational Radiation

Health Research 137

8.4 Radiation Science and

8.1 INTRODUCTION

As an occupational physician, most of my early recognition of ethics affect-ing workers focused on aspects of “professional practice” for those workers involved in areas such as health and social care These aim at the establishment

of norms of behavior for the appropriate management of patients or clients In

my own specialty, for example, for many years there has been published guid-ance of this type in the UK (The Faculty of Occupational Medicine, in press)

It is possible to extend these considerations, both for individual workers and their employing organizations as a whole, anywhere there is a customer

or stake-holder focus Customer relations can therefore be defined by “ethical standards” Other sections of this book take forward examples of these sorts of standards, such as those dealing with local communities

Separate from this customer focus, it is possible to look at ethical employ-ment based on treatemploy-ment and manageemploy-ment of the workers themselves Areas such as appropriate reward and recognition, training and development, absence

of discrimination or harassment, maintenance of confidentiality, and organiza-tional accountability all form the basis of many human resource policies, play-ing an important role in achievplay-ing staff engagement and shapplay-ing the culture of

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an organization In addition to arguments about ethical performance, in some

of these areas there is an increasing focus on statutory and regulatory require-ments, such as in the field of potential discrimination, in terms of disability legislation (The Equality Act, 2010) These requirements extend considerations

of ethics and culture into a more formal duty of care between an employer and their workforce

One such area covered both by ethics and legislation is the field of health and safety The current system of UK legislation goes back to 1974 (The Health and Safety at Work Act, 1974) although earlier systems were in place before that The system places a general duty on employers to ensure, so far as reasonably practicable, the health, safety, and welfare at work of their employees Within this general duty, consideration is given to the need for provision of informa-tion, instrucinforma-tion, training, and supervision These overarching requirements are established in enabling legislation and extended in single-subject statutory instruments dealing with specific hazards such as ionizing radiation (The

to precautions and controls, but also to information on the risks to health Ethi-cally, it seems sound to state that workers should have knowledge of the hazards

of their employment, as part of “informed consent” in their contract to work

On a practical level too, from my own experience, workers’ compliance with precautions and safety systems are much greater if they are fully aware of the hazards associated with noncompliance It also provides an effective mechanism

to avoid issues based on the traditional machismo of some occupational groups Worker ethics of radiation exposure thus should include the recognition that the employer owes the workforce a duty of care in terms of their protection from the radiation hazard, and also in terms of the provision of information about that hazard

8.2 RADIATION PROTECTION IN WORKERS

Ionizing radiation science is a young but extensive field While much of its biology and physics are highly complex, and indeed growing in complexity, the resultant systems of radiation protection, which enjoy a significant consensus across the political and scientific spectrum are fundamentally very simple This simplicity determines that they can be readily explained to radiation workers

At the basic level, concepts of whole body dose equivalence and committed dose, allow particularly complex issues of partial irradiation and contamination with radioactive material all to be dealt with in terms of a single numeric figure

of “dose” This figure is then the “cause” of deterministic and stochastic radia-tion effects that are perhaps more easily thought of in terms of radiaradia-tion killing cells or leaving them damaged in some way The thresholds for deterministic (cell killing) effects mean that these do not occur below certain radiation doses, and the linear nonthreshold dose-response relationship for stochastic (cell dam-age) effects determines that there is no safe dose, and that all doses contribute

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equally to risk Armed with this basic information, coupled with some knowl-edge of the existence of natural background radiation, what is meant by the terms radiation and contamination, the extent of medical exposure and basic cancer statistics, most workers are well able to suggest principles of radiation protection for themselves Unsurprisingly, these are not normally too dissimilar from those promulgated by the International Commission on radiological pro-tection, as justification, optimization, and limitation (ICRP, 1977)

Having been involved in the initial health surveillance of thousands of work-ers, I have always believed that the passage of this sort of knowledge is a prereq-uisite to allow a worker’s informed consent to accept “classified-worker” status (The Ionising Radiation Regulations, 1999)

While most radiation incident victims and fatalities in the world today are patients following medical exposure (IAEA, 2001), there remains a steady con-tinuous stream of workers subject to overexposure resulting from irradiation of product or site radiography (Lloyd et al., 1994) Justification that these practices are of benefit remains a key consideration Justification can, of course, change with time and understanding I am old enough to remember the routine irra-diation of my feet as a child, to assess the need for and fit of new shoes This practice is most definitely not justified now, based not only on dose to children but also occupational dose to shoe-shop staff Similarly, I well recall the fluo-roscopic mass radiography of the population for tuberculosis and brucellosis, again clearly not justified now, based on the current prevalence of both diseases Worker dose may well be the only consideration in the justification of practice

or it may be a component of a much more complex calculation of risk Looking, for example, at the disposal of the decommissioned nuclear power submarines: after the vessel has been defuelled, the vast majority of radioactive material remaining in the reactor compartment is 60Co from activation With the half life

of only about 8 years, storage as opposed to early dismantlement could there-fore eliminate the major contribution to worker dose and hence radiation risk Limitation and more recently optimization have had a significant effect on worker protection As an occupational health physician, it is interesting to track these changes in terms of changing requirements for statutory health surveil-lance, as improvements were made

In the early days of radiology, there was little or no dose control, save perhaps

“if your hands were red, you should stop work.” With the use of a deterministic (cell killing) effect for dosimetry, it is not surprising that further deterministic effects occurred in the hands and, more severely, causing aplastic anemia in these workers There are pictures of cancers developing on the stumps of fingers lost to deterministic damage in these early radiologists (Figure 8.1), and this, together with increased risk of leukemia, confirmed stochastic (cell damage) effects too At the same time, bone cancers in the predominantly female work-ers pointing their brushes with their lips as they painted radium dials (Figure 8.2) provided further evidence of worker risk (Baverstock & Papworth, 1989),

as well as the need to consider radiation protection as a whole, other than a

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specific concentration on a particular high focus area such as radiology With both deterministic and stochastic effects, health surveillance based on the early detection of disease was clearly indicated, including blood tests for determin-istic changes and regular screening for malignant disease The advent of dose controls brought the elimination of deterministic effects, but ongoing concern about stochastic risk Health surveillance was modified with initial blood test-ing to ensure that the worker did not have a hematological condition prior to work and ongoing periodic screening for disease Optimization in 1976 (ICRP,

1977) brought the concepts of as low as reasonably achievable (alara) and as low as reasonably practicable (alarp) Personal dose was no longer a resource that could be used, but something which needed to be minimized This resulted

in major reductions in both collective and personal dose levels In parallel,

FIGURE 8.1 Early radiologist’s hand showing malignant change superimposed on earlier

deter-ministic damage.

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large-scale epidemiological studies were published (Kendall et al., 1992) dem-onstrating that, while there may be some evidence for the expected increased cancer risk with the increased dose, cancer morbidity and mortality amongst radiation workers in the UK was significantly lower than for the population as

a whole Against this backdrop, health surveillance for the early detection of disease, self-evidently, was meaningless Health surveillance however has been retained as a mandatory requirement in Europe (96/29/Euratom, 1996) based on the basic principles of occupational medicine, and as a fit for work assessment,

to ensure that the worker is f it to undertake their role A further indication of the duty of care owed by the employer to the radiation worker

Effective dose control measures in radiology within the UK were introduced

in the early 1920s and their benefit in terms of risk reduction is well demon-strated by epidemiological study (Smith & Doll, 1981) Radium dial painting commenced on a large scale before World War I and bone sarcomas were rec-ognized by 1929 (Rowland & Lucas, 1984) Risk however continued until the 1950s, emphasizing the need for common and consistent radiation protection to cover all practices and uses

In more recent times, most public, media, and even perhaps regulatory focus has been on “nuclear” There has been very real reduction in individual dose

in this area Against this backdrop, however, in other areas of worker expo-sure, shockingly, we have seen even the recurrence of deterministic (cell killing) effects or suggestions of dose sharing as a radiation protection tool As medical use continues to expand, different workers have been involved In particular, in intervention radiology, deterministic skin effects have been reported since 1992

in doctors and other clinical staff where significant dose can be received for the hands (Streckelhuber et al., 2005) More recently, there are reports of cata-racts, another deterministic effect, in the same groups (Vano et al., 2010) These occurrences in new clinical groups have led the need for specific guidance from the International Commission on Radiological Protection (ICRP, 2013) which,

FIGURE 8.2 Primary bone cancer in a radium dial painter.

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not surprisingly, in addition to protection standard, emphasizes the need for training and knowledge about radiation risk for these workers

Although clearly not so dramatic as the reappearance of deterministic health effects, the arguments for consistency throughout all areas of radiation practice extend into other issues hugely relevant to worker dose, and worker understand-ing Against a backdrop of continued planned reduction in most radioactive dis-charges, nuclear medicine continues to develop and discharges from the medical field seem likely to continue to rise These result in critical group doses acquired occupationally to groups such as sewage workers, estimated to rival and even exceed dose from designated nuclear sites (UK Strategy for Radioactive Discharges, 2009) In the fields of Naturally Occurring Radioactive Material (norm) critical groups are workers, such as those in commercial kitchens (cook-ing with natural gas), whose doses are similarly comparable with those from industry (UK Department of Environment Food and Rural Affairs, 2002) While there may be major differences in what is “reasonably practicable” to achieve in terms of dose reduction between processes, if worker understanding and confi-dence is to be maintained, this must not extend into short hand incorrect simpli-fications and statements that doses in one area are trivial or “no danger” while other documentation decrees that similar doses elsewhere represent a continued risk that must be acted upon (UK Department of Environment Food and Rural Affairs, 2002)

Accident response and contingency planning provide another important area where there is a need to consider ethical issues in the worker role The fatalities and acute health effects in the Chernobyl liquidators (Ivanov, Gorski, Makutov, Tsyb, & Souchkevitch, 2001) provide high-profile evidence of the need to extend the employers’ duty of care in the areas of worker actions to control

or mitigate the consequences of accidents, as well as to implement actions to protect fellow workers or the public Just as in the earlier paragraphs, however, these considerations are not confined to issues around nuclear power plants, but extend throughout all areas where ionizing radiations are used

Basic statutory requirements (The Ionising Radiation Regulations, 1999) include the need to have contingency plans for reasonably foreseeable events,

as well as specifying the need for workers to be given suitable and sufficient instruction Worker considerations of this type are also included in statu-tory requirements for plans required in terms of public protection (Radiation

paragraphs, the issues of worker information must center around the hazard, and within that context, the knowledge of the events, which are planned for, as well as safety controls and protection Risk assessment must not be something that is considered solely in terms of statutory approval or licensing, but must form the basis of worker information on foreseeable scenarios Information

on the plan and the worker’s role within it is also crucial in terms of what needs to be done, how it can be done, and how monitoring and safety are to be maintained Knowledge of the equipment and systems that are required is also

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of importance Rehearsal adds greatly to understanding and is also a statutory requirement

8.3 ETHICAL REQUIREMENTS FOR OCCUPATIONAL

RADIATION HEALTH RESEARCH

Research has an accepted place in occupational medicine, based on the standard justification of any medically related study, the increase of human knowledge to the benefit of mankind (Royal College of Physicians, 1996) In the occupational setting, however, it is clear that there is an additional justification in support

of the health and safety for a specific group of workers upon whom the study

is conducted These two aims may be closely aligned but are not necessarily synonymous

An earlier paragraph of this chapter mentioned the UK epidemiological study of radiation workers, the so-called National Registry for Radiation Work-ers (NRRW) (Kendall et al., 1992) This was established with the clear desire to define numeric radiation risk estimates for workers, based on actual worker data This aim is being achieved by the so-called internal analysis of the study, which involves dividing the workers into dose bands, and looking for the expected increase in cancers as the dose increases As an individual who has been pro-fessionally involved in talking to radiation workers over many years, I have never felt any great worker interest in such numeric dose estimates Workers,

in the main, appear interested in safety of their employment in that particular situation As such, workers have traditionally paid much greater interest in the so-called external analysis of the NRRW, looking at mortality and morbidity in the radiation worker cohorts, compared with the population at large Together, the internal and external analyses provide a useful complete study that the two halves taken in isolation fail to achieve

The identification of the worker as a justification for, and also a customer

of, occupational radiation research, requires consideration of an ethical duty of care that the researchers must owe to these workers Without worker agreement

to participate, of course, in many cases no study could take place

The paragraphs that follow are equally applicable to all occupationally related studies Radiation, however, is one of those areas that is capable of attracting massive media and public interest; it is therefore not surprising that

it is the radiation workers that have suffered great distress, and it is those who have professionally attempted to provide service to the radiation workers that have attempted to take forward an ethical stance to protect them and others in the future

With the internet, and e-publication, systems of promulgation of the results

of health research are currently going through major revolution The basic prin-ciples, however, remain that a paper is submitted to a journal and, followed by a varying level of peer review, achieves publication It is a publication that allows wider academic review and hence the process by which a consensus on the

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merits of the work is taken forward In the modern world, however, additionally,

if the work has some potential for media impact, it may be subject to a prepubli-cation embargo Following press conference launch, there is an immediate gen-eral population knowledge through the full range of modern media Most of this occurs before the journal’s normal readership gets their copy through the post

In the 1990s, in particular, there were a number of studies involving radia-tion workers that attracted such media attenradia-tion Perhaps the most famous, and certainly the most distressing, was what became known as the Gardner Study, and its associated hypothesis (Gardner et al., 1990), that workers and their fam-ilies were told through headlines of mass circulation newspapers, radio, and television that radiation exposure at work to fathers was causally associated with the incidence of leukemia in their children With no, or limited, access to actual copies of the paper, few occupational health practitioners involved in the aftermath of the release of this study will ever forget the despair and anguish

it caused to real people, to whom we sought to provide occupational health advice

My own personal experience centers on a telephone call well before 7 a.m to

be asked if I had read the morning paper This was followed by a mad dash to the airport and a flight of approximately 90 min during which I did have sight of a newspaper Onto a car ride of 1 h, where for the first time I could read the scien-tific paper, before immediate entry into a large lecture theater holding hundreds

of radiation workers and their wives, and my attempts to answer their questions

It makes no difference whether the paper’s conclusions of hypotheses proved to

be correct or not, the situation is there and then, and workers require care and sensitivity I hope all would agree that this is no way to treat workers who are real people with families and concerns, who in many cases have consented to participate in the study in question In fact, of course, the Gardner hypothesis, years later, has not been supported by the evidence (Slovak, Kalman, Davies, & Pilling, 1994)

It is interesting to note that even before the publication of Gardner, consid-eration had already been given to some ethical aspects of occupational radiation research in the UK The NRRW from its outset had been an individual consent study, in which workers had to opt in unless their data could not be included Consent, therefore, is limited to the study as recorded within the NRRW pro-tocol and other researchers wishing to use NRRW data for their own purposes must revisit consent at least at the level of worker representatives This sort of system of consent recognizes the duty of care, which the researcher owes the worker, acknowledges the worker as a customer of the research, and is an issue that still needs to be addressed by those who periodically argue for increased accessibility and interchange of data (Smith, 1994) between researchers After the Gardner paper, and other studies with similar media headlines, the occupational physicians working in the nuclear industry in the UK agreed on a short ethical policy on future involvement in radiation health research This

con-sisted of four basic principles of medical confidentiality, worker information,

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worker consent and worker access to study results prior to publication Medical

confidentiality, of course, needs no further discussion, where actual medical data are involved in protocol These requirements for worker knowledge and consent however extend the established requirements for informed consent for invasive medical trials, and recognize workforce rights as customers of, and participants in, occupational health research The level of consent can of course vary in practice, depending on the research protocol The guarantee of prepub-lication information stems from an acknowledgment that it is both impractical and outside the occupational health remit to control media coverage of research, but nevertheless sought to accomplish the clear occupational health requirement

to provide the results to the customer accurately and in a way which their ques-tions could be answered and concerns could be addressed in a proper and appro-priate manner The requirement for consent, coupled with an acknowledgment

of the duty of care, allows for detailed consideration of prepublication briefings

at the protocol stage of research The rules are therefore laid down before the results are known This ensures worker knowledge irrespective of the nature of studies findings

This ethical stance, particularly in relation to prepublication notification of results, was agreed with the editors of the principle health-based journals within the UK such as the British Medical Journal and the Lancet While the policy was successfully implemented in a number of small radiation studies, ques-tioners at various presentations expressed some skepticism in relation to the practicalities of dissemination of such information in major national studies These concerns were essentially put to rest by the full implementation of the policy in relation to the publication of the UK’s national study investigating Gardner’s hypothesis by record linkage between the NRRW and childhood can-cer registries This piece of work involved data from 120,000 radiation workers with prepublication information available to workers in a number of different employment situations Despite this scale of workers and companies throughout the UK, a media embargo requested by the British Medical Journal, as publish-ers of the article, remained intact (Draper, Little, Sorahan, & Kinlen, 1997) The success of the implementation of the standards was also published (Kalman,

1999) As a result of these experiences, the guidance on ethics for occupational physicians in the UK, at its 5th edition in 1999, for the first time, included specific guidance on occupational health research This built upon the work undertaken by the occupational physicians in the nuclear industry, and has been maintained in subsequent editions (The Faculty of Occupational Medicine, in press) The principle ethical issues in research are identified as worker

recruit-ment , consent, confidentiality, data protection, and communication.

8.4 RADIATION SCIENCE AND WORKERS

In addition to the research based on worker data, academic or indeed medical research has the potential to attract media interest in radiation health, and also

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therefore to affect workers and their families Here, worker participation is not required, nor is there any contact with the employing organization and the aca-demic researcher Thus, any duty of care, and customer relationship, is much less clear The last 20 years have, however, seen issues identical both in support for greater and lesser radiation controls From radiation biology, the

establish-ment of genomic instability (Kadhim et al., 1994) and a growing level of knowl-edge on the circumstances when it occurs, led to suggestions for much higher

levels of radiation control On the other hand, the clear demonstration of

adap-tive responses (Wolf, 1998) has led others to suggest radiation hormesis (low doses of radiation are good for you) In radiotherapy, there has been continued interest in tests for radiation sensitivity as part of treatment planning (Wolf,

1998) Here there are questions on the relevance of tests based around cell kill-ing at doses of 10 s of Gray, when considerkill-ing the occupational situation of risks

of cancer at doses in the mili or micro sievert range More recently, sensitivity is shown at lower diagnostic dose levels (Foray, Colin, & Bourguignon, 2012) In the absence of researcher information here, it falls on government, regulator or expert international body to provide advice in a timeous manner which others can use to advise workers ICRP has taken on this role, and most recently, in

2005, confirming that the linear low threshold hypothesis remains the prudent base for radiation protection at low doses and low dose range (ICRP, 2004)

8.5 SUMMARY

In summary, radiation protection over the last 100 years has taken forward dra-matic increases in radiation control, with resultant reduction in worker dose and risk, with increased worker safety Even taking account of the expected healthy worker effects for large occupational epidemiological studies, radiation workers can be regarded as being involved in a safe industry

It is important not to regard the words “nuclear” and “radiation” as synony-mous Despite the dramatic dose reductions in the nuclear industry, determinis-tic effects are now being seen in radiation workers in new areas of medical use The consistent application of standards, together with the consistent provision

of advice and information remain the keystone of effective worker safety from the hazards of ionizing radiation

With radiation’s huge media profile, it was not surprising that radiation work-ers were the test cases in terms of the development of ethics of worker involve-ment in occupational research The identification that the researcher owes the worker a duty of care, and that the worker is a customer of the research, is achieving growing acknowledgment, not only confined to the radiation worker situation

With the profile of ionizing radiation research, there is a need for the timeous update of workers and their advisors, as radiation knowledge develops It is only

by this mechanism that continued confidence in radiation protection by workers can be maintained

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