|Year : 2011 | Volume
| Issue : 2 | Page : 114-118
Population dose from diagnostic procedures in Sindhudurg district of Maharashtra
SJ Dhawal1, PB Shete1, VA Karande1, AB Bandgar1, RJ Khyalappa1, SD Sharma2, SH Pawar1
1 Centre for Interdisciplinary Research, D.Y. Patil University, Kolhapur, India
2 RP and AD Section, BARC, Mumbai, Maharashtra, India
|Date of Web Publication||12-Jul-2012|
S J Dhawal
Centre for Interdisciplinary Research, D.Y. Patil University, Kolhapur
Source of Support: None, Conflict of Interest: None
The radiation exposure through medical diagnostic applications has one of the significant impact on human health in addition to other natural radiations. Most of the medical decisions are dependent on X-ray diagnosis. Although the patient is benefited by these X-ray procedures, knowledge of the radiation dose received by the patient during these radiological examinations is necessary. According to the International Commission on Radiological Protection recommendations all medical exposures should be subjected to the radiation safety principles of justification and optimization. Similarly International Atomic Energy Agency also recommended that the guidance levels for medical exposures shall be established for the use by medical practitioners and relevant professional bodies. Therefore, several studies have been carried out all over the world to establish proper guidance levels as well as made efforts in the reduction of unnecessary exposures. In this study, the survey of population exposed to medical X-ray diagnostics in the Sindhudurg district of Maharashtra, India has been carried out. For this study questionnaire was developed and used for the collection of data directly from the people as well as from diagnostic centres. The collected data was sorted according to type of examination, age and gender of the patient and presented here. Using this data collective effective dose and annual per caput effective dose for the Sindhudurg district were calculated. From the study it is concluded that the calculated effective dose per person per year for the region is of the order of 0.061 mSv that is lower than the average value across the global population that is of the order of 0.62 mSv as given in the UNSCEAR 2008 report.
Keywords: Collective effective dose, ionizing radiation, radiation exposure
|How to cite this article:|
Dhawal S J, Shete P B, Karande V A, Bandgar A B, Khyalappa R J, Sharma S D, Pawar S H. Population dose from diagnostic procedures in Sindhudurg district of Maharashtra. Radiat Prot Environ 2011;34:114-8
|How to cite this URL:|
Dhawal S J, Shete P B, Karande V A, Bandgar A B, Khyalappa R J, Sharma S D, Pawar S H. Population dose from diagnostic procedures in Sindhudurg district of Maharashtra. Radiat Prot Environ [serial online] 2011 [cited 2020 Aug 6];34:114-8. Available from: http://www.rpe.org.in/text.asp?2011/34/2/114/98398
| 1. Introduction|| |
X-ray is part of the electromagnetic spectrum and it has the highest energy range of all electromagnetic waves. It has ability to ionize atoms of the absorbing materials and this may be harmful for human body. X-rays are frequently used in diagnostic purposes and it was reported that diagnostic X-ray is the largest contributor to the annual per caput effective dose among the man-made source of ionizing radiation.  From the worldwide average it has been estimated that about 80% of the radiation dose to population is caused by X-ray examination for medical diagnostics.  Most of the medical decisions are dependent on X-ray diagnosis that cannot be ignored, especially when X-ray diagnostic facilities are being made available to larger sections of the society. Although the patient is benefited by these diagnostic procedures, knowledge of the radiation dose received by the patient during the radiological examination is necessary. 
The risk from exposure to ionizing radiation is dependent on the age at which the exposure occurs and that exposure during childhood is significantly responsible for certain detrimental effects compared with an adult. According to the International Commission on Radiological Protection (ICRP) recommendations all medical exposures should be subjected to the radiation safety principles of justification and optimization. Similarly International Atomic Energy Agency (IAEA) also recommended that the guidance levels for medical exposures shall be established for the use by medical practitioners and relevant professional bodies.  Therefore, several studies have been carried out all over the world to establish proper guidance levels as well as efforts are being made to reduce the unnecessary exposures to the patient. The study on medical exposure of the French population had been carried out by Etard et al.  in 2007. This study included diagnostic procedures from the imaging modalities as conventional radiology including dental radiology, computed tomography (CT), nuclear medicine, and interventional radiology restricted to diagnostic procedures. The main objective of their study was to characterize the exposure of the French population in 2007 according to the imaging modalities, to anatomical areas and to age as well as sex of the patient.  Similarly in the United Kingdom, study on radiation exposure of population from medical and dental X-ray examinations had carried out by Hart and Wall  that was published in March 2002. In the United States also a study had been carried out on medical radiation exposure by Mettler Jr. et al.  They had collected data from primary as well as secondary sources and reported that medical radiation exposure is now approximately equal to natural background radiation.  In India, studies related to dose from medical X-ray diagnostic examinations were carried out by Sonawane et al. , in 2010. They estimated the skin entrance doses (SEDs) for common medical X-ray diagnostic examinations and derived Diagnostic Reference Levels (DRLs). The survey on exposure to X-ray radiation per person per year from diagnostic procedures to the population of Rajasthan, India was carried out by Chougule et al.  The skin entrance and organ doses from medical X-ray examinations were also studied by Ramakrishnan and Padmanabhan. 
This study involves the population survey exposed to medical X-ray diagnostics in Sindhudurg district of Maharashtra, India. This district occupies an area of 5207 km  and has a population of 868825 according to 2001 Census.
| 2. Materials and Methods|| |
The survey was carried out in Sindhudurg district of Maharashtra, India. Hospitals in which the X-ray examinations carried out were approached, and those who readily responded, extended co-operation and were conveniently accessible to the authors were selected for the present study. Around 70% of the diagnostic centres were readily responded positively and 30% of diagnostic centres did not co-operate in the study. A questionnaire was used for the collection of data directly from the people as well as from diagnostic centres. The information asked through the questionnaire was: name, age, gender, and address of the patient; type of X-ray examination; site of examination; and number of examinations in a year.
The collected data were sorted according to the type of examination (site of examination: skull, limb, cervical spine, thoracic spine, lumbar spine, abdomen, hips, and chest), age (up to 1, 1 to 18, above 18) and gender of the patient (male, female): Our aim was to find out frequency of X-ray examinations in the Sindhudurg district to calculate collective effective dose (CED) and annual per caput effective dose. The CED and annual per caput effective dose for the district were calculated using the following relations (UNSCEAR 2008).
CED i = collective effective dose of the X-ray examination i
N i = annual frequency the X-ray examinations i
D i = established DRL of the X-ray examination i
| 3. Results and Discussion|| |
[Table 1] shows diagnostic reference levels of Sonawane et al. that was used for calculating the CED for the Sindhudurg district of Maharashtra.
The frequency of X-ray examinations and their CED values in Sindhudurg district are shown in [Table 2]. From this table it can be observed that 12214 X-ray examinations are carried out in about 60% population of the Sindhudurg district of Maharashtra. The highest frequency of diagnostic X-ray examinations are found for Limb followed by Chest and then L-Spine. The frequency of other diagnostic X-ray examinations is in the range of 216 to 593. The CED value for X-ray examination of L-Spine is higher than the CED of other X-ray examinations. This is due to the relatively higher DRL value of L-Spine which is highest among DRLs established for India. The CED value for other X-ray examinations are in the range of 1557 to 3717.
|Table 1: Diagnostic Reference Levels (DRLs) used for calculation of collective effective dose (CED)|
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|Table 2: Estimated number and collective doses from various X-ray examinations in Sindhudurg district|
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The annual per caput effective dose calculated for the Sindhudurg district considering 60% of population exposed to X-ray examinations is also given in [Table 1]. The annual per caput effective dose (which is also called as per caput dose) estimated for the Sindhudurg district due to X-ray radiographic examinations is 0.061 mSv that is less than the global average value of 0.62 mSv. This difference is due to the fact that only X-ray radiographic examinations are included in the present study whereas global average includes exposures from X-ray radiographic, fluoroscopic, mammography, computed tomography scanning, and dental X-ray examinations.
The frequency distribution (%) of X-ray examinations for Sindhudurg district is shown in [Figure 1]. Inspection of this figure indicates that the Limb and the Chest are the parts of the body for which X-ray examinations carried out are most frequently in the Sindhudurg district. This frequency of X-ray examination for Sindhudurg district is also compared with world averages obtained from UNSCEAR 2008 report  that is given in [Table 3]. From this table it is observed that the frequency contribution (%) of X-ray examinations for present study is higher for almost all the anatomical parts than world average values except for abdomen X-ray that is 1.8% in comparison to world average value of 5%. This study also indicates that the most frequently examined body part in Sindhudurg district is limb and chest comes second whereas world average values indicate that most frequently examined body part is the chest and limb comes second. We cannot get world average value of frequency contribution for skull X-rays and hence its global average data is not quoted here.
[Figure 2] presents information on various X-ray radiographic procedures. The vast majority of CED comes from examinations of L-Spine followed by Limb and Chest X-ray. X-rays of L-spine, Limb and Chest account for about two-thirds of the CED. The CEDs calculated for X-ray radiographic procedures for Sindhudurg district are also compared with world average (UNSCEAR2008)  values of CEDs which is shown in [Table 4]. From this table also it is found that the collective effective dose contribution from L-spine according to world average value is higher than any other type of X-ray examination. From the [Table 4], it is observed that the present study values for CED contribution (%) for X-ray examinations are higher than world average (UNSCEAR2008)  values for CED contribution (%).We cannot obtain world average value of CED percentage contribution for skull X-rays so it is not compared.
|Figure 1: Estimated frequency percentage distribution of X-ray examinations in Sindhudurg district|
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|Figure 2: Estimated collective effective dose percentage distribution for X-ray examinations in Sindhudurg district|
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|Table 3: Comparison of frequency contribution between world average (UNSCEAR 2008) values and present study values|
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|Table 4: A Comparison of CED contribution (%) for diagnostic X-ray examinations between world average (UNSCEAR 2008) value and the present study value|
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The available data on diagnostic X-ray examinations is also analyzed according to age distribution of patients which is shown in [Table 5]. From the [Table 5], it is observed that the total number of people exposed to X-ray examinations is 9113 from which new born babies up to 1 year old are 22, age group from 1 to 18 year old is 1357 and above 18 years is 7734. It is found that, people from age group above 18 years are exposed more to the Chest, Limb and L-Spine X-ray examinations. The age group between new born babies to 1year old and 1 to 18 year old is comparatively lower.
|Table 5: Age distribution of the patients underwent the X-ray examinations in Sindhudurg district|
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Similarly the data is analyzed with reference to gender distribution. It is observed that total number of exposed population has highest count of male population than the female which is exposed to the X-ray examinations particularly to limb and chest X-ray. It is observed that less number of females is exposed to X-ray examinations for abdomen and T-Spine.
[Figure 3] shows the distributed number of male and female exposed to all eight types of X-ray examinations in Sindhudurg district. In every type of X-ray examination, number of females exposed is less than the number of males. But, both the male and female population is exposed between the range of 96 to 230 for Skull, Abdomen, C- Spine, T- Spine and Hip.
|Figure 3: Estimated gender distribution exposed to X-ray examinations in Sindhudurg district|
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In several studies, it has been concluded that there is a need to optimize the protection of patient's results from the fact that medical exposure is by far the largest source of radiation exposure of artificial origin. The average effective per caput dose ranges between 0.5 and 2 mSv in the developed countries, at a level corresponding to a significant fraction of the dose received from exposure to natural radiation. The practice of exposing patients to ionizing radiations is clearly justified because the clinical benefit of the medical examination outweighs the risk associated with the exposure to ionizing radiations. The ultimate objective is to perform only useful procedures which result being positive or negative is expected to comfort the diagnosis or to change patient management; otherwise, the practice is not justified. According to the UNSCEAR 2008 report,  the annual per caput effective dose for the various health care levels and the average value across the global population is 0.62 mSv from diagnostic, medical and dental radiological examinations. The calculated effective dose per person per year is compared with this global value of annual per caput effective dose. 
| 4. Conclusion|| |
Radiation exposure through medical diagnostic X-ray examinations is one of the highest contributor of annual per caput effective dose in comparison to other sources of man-made. The annual per caput effective dose estimated from this study is 0.061 mSv that is lower than the global average value of 0.62 mSv as reported in UNSCEAR 2008 report.  Further detailed study is necessary for obtaining the actual annual per caput effective dose for optimization and justification of medical diagnostic practice in Sindhudurg district of Maharashtra.
| 5. Acknowledgement|| |
Authors are thankful to DAE-BRNS for their financial assistance to carry out the work. Authors are also thankful to research students of Centre for Interdisciplinary Research, D. Y. Patil University, and Kolhapur for their co-operation. They are very much grateful to Dr. P. C. Verma and Dr. M. P. Chougaonkar from BARC for their encouragement.
| References|| |
|1.||Available from: th http://eprints.usm.my/15519/1/ESTABLISHING_DOSE_REFERENCE_LEVEL_FOR_COMPUTED.pdf [Last accessed on 2011 Nov 02]. |
|2.||Sonawane AU, Shirva VK, Pradhan AS. Estimation of Skin Entrance Doses (SEDs) for common medical X-ray diagnostic examinations in India and proposed Diagnostic Reference Levels. Radiat Prot Dosim 2010; 138:129-36. |
|3.||Chougule A. Contribution of patient radiation dose per person per year to overall annual per caput effective dose due to X-ray diagnostic procedures. J Med Phys 2004; 29:30-33. |
|4.||Sonawane AU, Sunilkumar JV, Singh M, Pradhan AS. Suggested Diagnostic Reference Levels for paediatric X-ray examinations in India. Radiat Prot Dosim 2011; 147:423-. |
|5.||Etard C, Aubert B, Sinno-Tellier S. Medical exposure of the French population in 2007. Proceedings of Third Europian IRPA Congress 2010 June14-18. Helsinki, Finl. |
|6.||Available from: th http://medicalphysicist.co.uk/nrpb_w4.pdf [Last accessed on 2011 Nov 02]. |
|7.||Mettler FA Jr, Thomadsen BR, Bhargavan M, Gilley DB, Gray JE, Lipoti JA, et al. Medical radiation exposure in the U.S. in 2006: Preliminary results. Health Phys 2008; 95:502-7. |
|8.||Ramkrishnan G, Padmanabhan V. Skin Entrance and Organ Doses from Medical X-ray examinations. J Med Phys 2000; 25:256-262. |
|9.||United Nations Scientific Committee on the Effects of Atomic Radiation. Sources and effects of ionizing radiation. Volume I, UNSCEAR 2008 Report to the general Assembly, with scientific annexes. New York: United Nations, 2010. |
[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]