Protecting female healthworkers from ionising radiation at work
BMJ 2023 ; 381 doi: https://doi.org/10.1136/bmj-2023-075406 (Published 12 April 2023) Cite this as: BMJ 2023;381:e075406
- Isobel Pilkington , core surgical trainee 1 ,
- Hannah Sevenoaks , specialty trainee trauma and orthopaedics 2 ,
- Emily James , radiation protection supervisor for theatres 3 ,
- Deborah Eastwood , president 4
- 1 Wessex Deanery
- 2 North West Deanery
- 3 King’s College Hospital NHS Foundation Trust, London, UK
- 4 British Orthopaedic Association
- Correspondence to: I Pilkington isobel.pilkington{at}nhs.net , British Orthopaedic Association info{at}boa.ac.uk
Exposure to ionising radiation during image guided procedures has been associated with a higher incidence of breast cancer in female healthcare workers. 1 2 3 4 5 6 Lead or lead equivalent gowns are used to reduce radiation exposure during image guided procedures, but studies have shown that current gowns provide inadequate protection to breast tissue as they leave the upper outer quadrant and axilla exposed. 7 8
Ionising radiation is a known human carcinogen, and breast tissue is highly radiation sensitive, with a linear relationship between increasing exposure and increasing risk. 9 One in seven women will develop breast cancer, and most are in the upper outer quadrant of the breast. 10 Breast cancer is a multifactorial disease with genetic, environmental, and occupational risk factors. Ionising radiation is a mitigatable factor, and exposure should be kept as low as reasonably practicable. 11 Providing protective gowns with adequate breast covering could reduce radiation exposure and potentially help prevent breast cancer in female healthcare workers.
Increased risk
Quantifying the risk of occupational radiation induced breast cancer in women working in healthcare is challenging because longitudinal data have not been widely collected. Data acquisition is complicated by the interval between exposure and development of disease, and the relatively small number of women working in image guided specialties. At consultant level, women make up 7%, 12%, and 16% of the UK trauma and orthopaedic, interventional radiology, and cardiology workforces, respectively. 12 13 14 15 As the number of female trainees entering these specialties increases, it is essential that the risks are further investigated, available evidence is considered, and equipment provision improved to minimise this risk. 12 13 14 15
Existing observational evidence suggests a link between exposure to ionising radiation at work and breast cancer. Studies of female US orthopaedic surgeons reported a 2.9-fold to 3.9-fold increase in the prevalence of breast cancer, compared with an age matched female population. 1 2 3 The risk persisted at double the expected level after sensitivity analysis to address selection bias. Female plastic and urological surgeons, who had similar lifestyles and pregnancy histories to the orthopaedic surgeons, did not share this increased risk. 2 A small Finnish study highlighted that breast cancer occurred at 1.7 fold the expected rate in radiologists, surgeons, and cardiologists compared with female physicians not working with radiation. 4 Increased rates of breast cancer have also been found in cohorts of US and Chinese radiological technologists. 5 6 Male breast cancer is rare, accounting for 1% of total cases. 10 Diagnostic and therapeutic ionising radiation has been implicated in its development, but two literature reviews have not identified occupational radiation exposure as a risk factor. 16 17
To quantify radiation exposure to the upper outer quadrant, researchers attached dosimeters to the upper outer quadrant of the breast of an artificial female torso that was wearing commonly used protective equipment. 8 Simulated intraoperative positioning showed a large variance in radiation exposure, inadequate protection of the upper outer quadrant, and no significant reduction in dose when a standard protective gown was compared with a torso without protection. 7 8 A separate study that placed dosimeters over a standard protective gown worn by orthopaedic surgeons identified that the area adjacent to the axilla received the highest radiation dose in the upper body. 18
The International Commission on Radiation Protection revised its guidelines in 2007 to double the relative detriment of ionising radiation for breast cancer, due to a historical underestimation of the impact of ionising radiation on breast tissue. 19 No occupational dose limits exist for breast tissue, in contrast to other radiation sensitive areas such as the eyes and thyroid. Clear guidelines on an acceptable dose of ionising radiation to the female breast would facilitate improvements in governance of radiation exposure in the workplace.
Better protection
The Ionising Radiation Regulations 2017 state that the radiation dose delivered to workers should be as low as reasonably achievable (the ALARA principle). 11 The most effective ways to accomplish this are reducing the duration of exposure, increasing the distance from the source, and shielding all workers with effective protective clothing. Current standard gowns cover the torso, reproductive organs, and femurs, with additional thyroid protection available. Possible designs to protect the upper outer quadrant of the breast include axillary shields, sleeves that can be worn under standard gowns, gowns with capped sleeves, and axillary wings. The addition of axillary coverage or sleeves has been found to decrease intraoperative irradiation to the upper outer quadrant by 99%. 8 Each new design to the market should be tested rigorously before claiming that it protects the upper outer quadrant. The European Society for Vascular Surgery has already recommended that female operators consider adopting this additional protection. 20
Employers worldwide have a duty of care to workers exposed to ionising radiation, and therefore should provide adequate protection. The female breast seems to be particularly vulnerable, and it is therefore important employers invest in protective equipment that enhances the safety of all their staff.
Footnotes
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We thank Lynn Hutchings, Charlotte Lewis, Caroline Hing, Fergal Monsell, Charline Roslee, Sarah Clark, and William Eardley for their commitment and valued contribution to this editorial.
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Competing interests: The BMJ has judged that there are no disqualifying financial ties to commercial companies. The authors declare no other interests. Further details of The BMJ policy on financial interests are here: https://www.bmj.com/sites/default/files/attachments/resources/2016/03/16-current-bmj-education-coi-form.pdf .
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Provenance and peer review: Not commissioned; externally peer reviewed.