Consumer products and activities, industrial sources, and occupational exposure also contribute to the amount of artificial radiation received by the U.S. population, although the amount of radiation received in this way is small. Sources derived from consumer products and activities include building materials, commercial air travel, cigarette smoking, mining and agriculture, combustion of fossil fuels, road construction materials, television, and glass and ceramics contribute approximately 2% of the total annual effective dose per person. (United States Nuclear Regulatory Commission, 2020). Industrial radiation includes sources such as nuclear power generation; disposal of nuclear waste; airport inspection systems; and industrial, medical, educational, and research activities. Occupational exposure is employee-related radiation exposure that occurs in a variety of work situations, such as medical (includes dental and veterinary medicine), aviation, nuclear power, military, academic, and industrial environments. Among occupationally exposed individuals, the medical and aviation categories comprise the greatest number of workers and the highest collective effective dose. Individuals in the aviation industry experience a higher concentration of natural radiation at higher altitudes due to a higher amount of radiation from cosmic rays present at higher altitudes than the level of cosmic radiation at ground level (Alden, 2020). However, industrial and occupational sources combined account for less than 0.01% of the total annual effective dose per person. Table 4 summarizes radiation sources and exposure doses, revealing that the radiation from natural and artificial sources results in an average effective dose of 6.2 mSv per year for persons living in the United States (United States Environmental Protection Agency, 2021b). Table 3: Diagnostic Examinations with Typical Effective Dose Type Examination Effective Dose (mSv) Effective Dose (mrem)
Table 3: Diagnostic Examinations with Typical Effective Dose Type Examination Effective Dose (mSv) Effective Dose (mrem)
FM survey PSP or F-speed film round collimation Dentoalveolar CBCT small and medium field view Maxillofacial CBCT large field view
0.171
17.1
0.011 to 0.674
1.1 to 67.4
Dental
0.030 to 1.073
3 to 107.3
FM = full mouth; PSP = photostimulable phosphor; CBCT = cone beam computed tomography. Note . Adapted from American Dental Association. (2016). Oral health topics: X-rays. Retrieved from http://www.ada.org/en/member- center/oral-health-topics/x-rays; (American Dental Association, 2019; Health Physics Society, 2021; Effective doses in radiology and diagnostic nuclear medicine: A catalog. Radiology, 248 (1), 254-263; and Radiological Society of North American. (2016). Radiation dose in X-ray and CT exams: Effective radiation doses in adults . Retrieved from http://www.radiologyinfo.org/en/info.cfm?pg=safety-xray#safety- benefits-risks. Table 4: Source Contribution to Annual Effective Dose
Effective Dose (mrem)
Radiation Source Radon (internal inhalation)
Percent Contribution
Effective Dose
Type
37
2.28
228
Cosmic (space)
5
0.33
33
Natural 3.1 mSv
Chest radiography
0.1
10
Medicine (exposure from single diagnostic x-ray)
Internal terrestrial External terrestrial
5
0.29
29
Mammography
0.4
40
Upper GI series
6.0
600
3
0.21
21
Coronary CT angiography
12
1,200
Computed tomography
24
1.47
147
Kidney (filtration rate) 99mTc DTPA Thyroid scan (sodium iodide-123) Bone scan 99mTc MDP
6.0
600
Nuclear medicine
12
0.77
77
1.9
190
Nuclear medicine (exposure from entire procedure)
Medical 3.0 mSv
Interventional fluoroscopy Conventional radiography/ fluoroscopy (dental 2.5%)
7
0.43
43
6.3
630
5
0.33
33
Brain (PET) 18F FDG 14.1
1,410
Heart stress-rest test 201Tl chloride
41
4,100
Consumer
2
0.13
13
Four bitewings PSP or F-speed film rectangular collimation
0.005
0.5
Other 0.1 mSv
Occupational
<0.1
0.005
0.5
Industrial
<0.1
0.003
0.3
Total 620 Note : Adapted from Health Physics Society, 2020; United States Nuclear Regulatory Commission, 2020. All sources 100 6.2
Dental
Panoramic
0.01
1
FM survey PSP or F-speed film
0.035
3.5
rectangular collimation
Page 112
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