Issue
Radioprotection
Volume 56, Number 4, October - December 2021
Page(s) 303 - 308
DOI https://doi.org/10.1051/radiopro/2021028
Published online 14 October 2021

© SFRP, 2021

1 Introduction

Ionizing radiation (IR) is widely used in the medical field to diagnose and treat diseases. There has been an increase in the numbers of diagnostic and therapeutic procedures, which, in turn, has increased the occupational radiation doses delivered to healthcare practitioners (Smith-Bindman et al., 2008; UNSCEAR, 2008). Nurses are among several healthcare practitioners who play a pivotal role in patient care for patients undergoing diagnostic or therapeutic procedures in various departments, including the operating room (OR), cardiac catheterization laboratory (cath-lab), endoscopy, general X-ray, computed tomography (CT), fluoroscopy, dentistry, angiography, nuclear medicine (NM), urology, radiotherapy (RT) and mammography. Nurses assist in demonstrating procedures, patient preparation, inserting IVs, monitoring patients’ vital signs and they are responsible for the safety and comfort of patients during various procedures. Consequently, they are at risk of being exposed to the harmful effects of IR. Nurses in these departments can be exposed to low-level IR over long periods of time (chronic exposure), which can be associated with various biological effects (NRC, 2006; Sahin et al., 2009; Covens et al., 2012). Several epidemiological studies conducted on medical radiation practitioners have reported increased risks of leukaemia and breast cancer (Yoshinaga et al., 2004), while other studies have reported an association between occupational radiation exposure and malignant tumours, cardiovascular disease (Gillies et al., 2017) and cataracts (Jacob et al., 2013). The Association of periOperative Registered Nurses (AORN) in the United States has made recommendations to reduce radiation exposure in OR nurses and radiation medical workers (AORN, 2007).

In Saudi Arabia, the radiation protection program (RPP) of the Ministry of Health (MOH) is in charge of monitoring occupational doses for all medical radiation practitioners, including nurses, and providing personal dosemeters to be used in the workplace. The RPP uses thermoluminescent dosimeters (TLDs) as the standard personal radiation monitoring devices. TLDs are designed to measure the occupational dose in terms the whole-body effective dose, the personal dose equivalent (Hp[10]). The recommended dose limit for an effective dose is 20 mSv averaged over 5 consecutive working years, with the condition that the dose should not exceed 50 mSv in any single year. (ICRP, 2007; IAEA, 2018). Analyses of occupational doses (trends in the annual mean effective and collective doses and the dose distribution) are an important component of institutional RPPs and can be used as indicators of good institutional radiation safety practices (Al-Haj et al., 2004). According to the International Atomic Energy Agency, the individual occupational radiation dose record should be evaluated every five consecutive years for averaging purposes to determine whether doses were as low as reasonably achievable (IAEA, 2018).

Monitoring and analysing occupational radiation doses for medical radiation practitioners, including nurses who work in departments using IR, are necessary to ensure a safe work environment and eliminate radiation injuries. Currently, there are no studies in Saudi Arabia that have evaluated radiation doses to nurses on a national level. Therefore, the purpose of this study was to estimate a baseline for the occupational effective doses for five consecutive years (2016–2020) among nurses working in several medical departments in Saudi Arabia.

2 Methods

2.1 Study population

During the five-year period from 2016 to 2020, 3249 nurses (83.6% female and 16.4% male) were monitored to assess their radiation effective dose during their work routine in the OR, general X-ray, cardiac catheterization laboratory (cath-lab), endoscopy, CT, fluoroscopy, dentistry, angiography, NM, urology, RT and mammography departments. The number of monitored nurses in 2016, 2017, 2018, 2019 and 2020 were 339, 409, 560, 857 and 1084 nurses, respectively. The number of nurses monitored for occupational exposure increased during the study period. This is due to the increase in the recruitment of nurses as a result of rapid growth of the Saudi population and healthcare services. The distribution of nurses in each department is shown in Table 1. The nurses involved in this study had an average age of 36.25 years with an age range of 22–64 years, and they were employed in 412 Saudi MOH healthcare facilities in all 13 Saudi administrative regions.

Table 1

Distribution of nurses in each medical department.

2.2 Dosimeters and calibration

TLDs were used to monitor the personal radiation doses. The MOH radiation protection offices in each region were in charge of distributing and collecting the TLDs on a quarterly basis, which allowed for an estimate of the effective dose received by the nurses. Nurses were issued personal bar-coded TLDs that contained each nurse’s name, sex, date of birth, department and previous radiation dose records. All nurses were asked to place their TLDs at chest level on the trunk of the body to adequately estimate their whole-body radiation dose. The effective dose was calculated by setting it equal to the measured Hp(10), which may be adequately considered a conservative assessment of the effective dose under the assumption of uniform whole-body exposure (UNSCEAR, 2008).

The TLDs used in this study (TLD-100 chip; Thermo Fisher Scientific, Massachusetts, United States) were made of lithium fluoride (Li natural) LiF:Mg.Ti materials. The TLDs had an emission spectrum of 3500 to 6000 Å, an energy response of 1.25 keV/6° Co, a sensitivity of 1.0 at 6° Co relative to LiF and a measurement range of 10 pGy to 10 Gy. For the TLD reading process, a Harshaw Model 6600 Plus Automated Reader Instrument (Thermo Electron Corporation, Ohio, USA) was used. The reader had a dose range of 10 μGy to 1 Gy. The reader was calibrated by exposing the calibration dosemeter to a 137Cs source free in air to a 0.5 mSv. Since the efficiencies of thermoluminescence signals in each chip may vary, the built-in internal irradiator (90Sr/90Y) in the reader was utilised to generate element correction coefficients (ECCs) to ensure that all TLDs provided the same response to a given radiation dose (Mora and Acuña, 2011; Alashban and Shubayr, 2021). For background radiation subtraction, a set of control TLDs was used to measure the background radiation. The background radiation was subtracted from the reading of each TLD.

2.3 Statistical analysis

Descriptive analyses of the dosimetry data along with a one-way analysis of variance (ANOVA) and Tukey honestly significant difference (HSD) post hoc test were performed at a 95% confidence interval. All statistical analyses were performed using the Statistical Package for the Social Sciences (SPSS v. 20, IBM Inc., Chicago, IL, USA).

3 Results

The analysis of the dosimetry data from 12 996 TLD badges (4 badges per nurse annually) were performed to obtain the occupational exposure of nurses employed in various hospital departments in Saudi Arabia (2016–2020). The mean annual effective dose (MAED) and the mean collective effective dose (MCED) were an indicator of the overall occupational exposure for nurses in each specific medical department. The maximum annual effective dose was 13 mSv for a nurse who worked in the cath-lab department. As shown in Figures 1 and 2, the overall MAEDs and MCEDs during the study period were well below the permissible annual dose limit of 20 mSv.

thumbnail Fig. 1

MAED for nurses in each specific medical department during the study period.

thumbnail Fig. 2

MCED for nurses in each specific medical department during the study period.

4 Discussion

Analysis of occupational radiation doses for nurses in medical departments involving IR procedures are vital to establishing a baseline overall MAED for nurses in the country and evaluating the MAEDs in different departments. In this study, analysis of dosimetry data for all nurses in all departments during 2016–2020 revealed that the overall MAED was 0.85 mSv. The results show no trend for MAED for nurses in each specific medical department according to each calendar year. However, an increasing trend was observed for MCED according to each calendar year due to the increase in the radiological procedures and the recruitment of nurses during the study period. Table 2 shows cumulated occupational radiation dose (mSv) over the 5-year period for nurses in the medical departments during the study period. The results show that nurses working in OR departments received the highest cumulated occupational radiation dose because they represent the largest number of nurses compared to nurses in other departments.

A one-way ANOVA was carried out to determine if there were significant differences in the MAEDs between the nurses in various medical departments. The results showed significant differences in the MAEDs between nurses (F [16.91;1037.08] = 4.79, p = 0.000). Tukey HSD post hoc test revealed that the MAED for the cath-lab nurses was significantly higher than the MAEDs for OR, CT, and endoscopy nurses. Furthermore, no other significant difference was observed in occupational exposure between medical departments.

This study found that nurses exposed to the highest MAEDs were nurses in NM, followed by the cath-lab. Nurses performing NM procedures were the most exposed group (1.01 mSv) among all nurses. The MAEDs for nurses in NM in Saudi Arabia was lower than nurses performing NM procedures in other countries, such as South Korea (2.12 mSv) (Jang et al., 2020), Kuwait (3.2 mSv) (Alnaaimi et al., 2017), Poland (4.0 mSv) (Piwowarska-Bilska et al., 2011) and Portugal (3.18 mSv) (Martins et al., 2007), but higher than that in the United Kingdom (0.4 mSv) (Oatway et al., 2016). During the nurses’ work routines in the NM department, external exposure occurs when they work close to the patients. For instance, they work close to patients when they administer radiopharmaceuticals, position patients and conduct image acquisition. The radiation exposure received by nurses is most likely due to the amount of time these nurses spend in close proximity to patients during and after the administration of radiopharmaceuticals (Oatway et al., 2016; Health Canada, 2018). Similarly, within all medical departments, NM technologists were reported to be the most highly exposed workers among all others (Oatway et al., 2016; Alnaaimi et al., 2017). Unlike general X-ray and CT nurses, the nurses who performed cath-lab procedures stand in close proximity to the patient and X-ray generator, and consequently, they are exposed to considerable amounts of scattered radiation (Kim et al., 2012; Wilson-Stewart et al., 2018). The MAED for nurses performing cath-lab procedures was approximately 0.97 mSv, which was higher than nurses performing general X-ray (0.90 mSv) and CT scans (0.77 mSv). The MAED for nurses working in the cath-lab department was in the lower dose range for cardiologists, radiologists, anaesthesiologists, medical students and medical assistants, who perform cath-lab procedures in Saudi Arabia (0.09–4.51 mSv) (Shubayr and Alashban, 2021).

During the study period, MAEDs for nurses working in the general X-ray and mammography departments were 0.90 and 0.77 mSv, respectively. This dose was significantly higher than that for nurses in developed countries, such as Canadian nurses (0.27 mSv) (Teschke et al., 2007) and United Kingdom nurses (0.06 mSv) (Oatway et al., 2016). The MAED for nurses is higher than the average MAED for radiologic technologists (0.88 mSv) in Saudi Arabia (Shubayr et al., 2021) but lower than the worldwide average (1.34 mSv) for medical radiation practitioners (UNSCEAR, 2008).

The MAED for nurses working in dentistry was 0.92 mSv, which was higher than the worldwide average (0.89 mSv) (UNSCEAR, 2008), and the Saudi average (0.72 mSv) (Alashban et al., 2021) for dental practitioners. For OR nurses, the MAED was 0.81 mSv, which was lower than the OR nurses from Spain (< 0.1 mSv/month) (Andrés et al., 2017).

For nurses working in the endoscopy and urology departments, the MAEDs were 0.79 and 0.68 mSv, respectively, which is significantly lower than the estimated range of MAEDs for endoscopists (3.35–5.87 mSv) (Naidu et al., 2005). Likewise, the MAEDs for nurses working in the fluoroscopy and angiography departments were 0.81 and 0.91 mSv, respectively, which is lower than MAEDs for interventional radiology workers in Kuwait (1.63 mSv), Iran (1.33 mSv) and Romania (3.58 mSv) (UNSCEAR, 2008). However, they were higher than workers in the United Kingdom (0.21 mSv) (UNSCEAR, 2008). Similarly, the MAED for nurses working in the RT department was 0.67 mSv. This dose was lower than the reported MAED in Pakistan (0.70 mSv) (Zafar et al., 2015), but higher than in Lithuanian (0.20 mSv) RT workers (Samerdokiene et al., 2015).

The knowledge and level of awareness about radiation protection practices could be possible explanations for the higher doses among nurses compared to radiologic technologists in Saudi Arabia. Several studies have reported poor levels of knowledge and awareness and a lack of standard education of radiation protection among nurses (Alzubaidi et al., 2017; Hirvonen et al., 2019; Shafiee et al., 2020; Behzadmehr et al., 2021). Personal protective equipment, such as lead aprons, lead gloves, lead glasses, thyroid shields and surgical caps, is significantly related to a drop in the amount of radiation exposure. Moreover, the position and movement of the workers during the same radiological procedures may contribute to radiation dose variations (Madder et al., 2018). Unlike radiological technologists, who mainly stay stationary throughout the radiological procedures, nurses are usually mobile during these procedures (Madder et al., 2018).

Table 2

Cumulated occupational radiation dose (mSv) over the 5-year period for nurses in the medical departments during the study period.

5 Conclusion

A national study was conducted from 2016–2020 to investigate the occupational doses among Saudi nurses working in several departments where radiological procedures are performed. The result revealed that the nurses’ overall MAED, in all departments during the study period was 0.85 mSv. In comparing MAEDs in different departments, nurses in NM received the highest MAEDs (1 mSv) followed by those working in the cath-lab (0.92 mSv). The MAEDs in all departments were below the recommended occupational dose limits, which indicate a safe work environment. However, to further reduce the occupational dose, we recommend training and continuing education in radiation protection for nurses involved in radiological procedures.

Acknowledgments

The authors extend their appreciation to Deanship of Research, Jazan University, for supporting this research work through the Research Excellence Program.

References

Cite this article as: Shubayr N, Alashban Y. 2021. Occupational radiation doses among nurses working in several medical departments in Saudi Arabia: a five-year national study. Radioprotection 56(4): 303–308

All Tables

Table 1

Distribution of nurses in each medical department.

Table 2

Cumulated occupational radiation dose (mSv) over the 5-year period for nurses in the medical departments during the study period.

All Figures

thumbnail Fig. 1

MAED for nurses in each specific medical department during the study period.

In the text
thumbnail Fig. 2

MCED for nurses in each specific medical department during the study period.

In the text

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