Goals of radiation safety management
Guidelines for facility management
Characteristics and legal positioning
Physical properties of 90Y
Nuclide | Half-life | Type of decay | Maximum energy (MeV) of β rays and percentage emitted | Photon energy (MeV) and percentage emitted | Effective dose rate constant (μSv m2 MBq−1 h−1) |
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90Y | 64.00 h (2.67 days) | β− | 2.280–100% | None | 0.00263a |
In vivo dynamics of 90Y
Exposure dose of this drug
Relevant laws, ordinances, rules, and regulations
Legal definitions
Requirements for trial site (legal requirements)
Requirements for trial site
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Name and location of the hospital or clinic.
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Types, shapes and quantities of medical radionuclides that are scheduled to be used in the year.
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Planned maximum storage quantity, planned maximum quantity used in 1 day, and planned maximum quantity used in 3 months for each type of medical radionuclides.
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Overview of buildings and facilities and precautions for the prevention of radiation injuries of the room where medical radionuclides are used, storage facilities, transportation containers, disposal facilities, and rooms where patients treated with medical radionuclides are admitted.
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Names of physicians using medical radionuclides and their background for radiology.
Rooms where medical radionuclides are used | Medical Care Act |
Rooms where medical radionuclides are used | Rooms where medical radionuclides are useda |
Storage facilitiesb | |
Disposal facilitiesc | |
Rooms for patients undergoing radiation therapyd | |
Dose limits and concentration limits in controlled arease | The effective dose of external radiationf: 1.3 mSv every 3 months Concentration of radioactive isotopes (hereinafter referred to as RIs) in the airf: the average concentration over 3 months is 1/10 of the concentration limit of an RI in the air Surface density of a material contaminated with an RIf: 1/10 of the surface concentration limit (RIs that do not emit alpha rays: 4 Bq/cm2) |
Dose limits and concentration limits at places in facilities using RIs where people are constantly enteringa–c | The effective dose on the external side of walls, etc.: 1 mSv or less every week Concentration of an RI in the airf: The average concentration over 1 week is equal to the concentration limit of an RI in the air Surface density of a material contaminated with an RIf: Surface concentration limit (RIs that do not emit alpha rays: 40 Bq/cm2) |
Dose standards at boundaries in a hospital or other medical facility (including areas in the hospital where people stay)g | The effective dose is 250 μSv or lessf every 3 months |
Exposure dose for inpatientsh | The effective dose does not exceed 1.3 mSv every 3 months |
Notification regarding the quantity of medical radionuclides to be used
Site criteria (requirements for safety management system)
Safety management system
Establishment of safety management system
Education and training related to radiation safety management
Designation and responsibilities of a radiation safety supervisor
Designation and responsibilities of a radiation safety officer
Site criteria (other matters to be complied with)
Safety management of this product
Record keeping
Restrictions on places where radiopharmaceuticals can be used
Control of exhaust, drain water and place of use, and concentration limit
Preparation and administration of yttrium-90-labeled anti-P-cadherin antibody injection
Composition and preparation of this drug
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Anti-P-cadherin antibody solution vial.
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Buffer solution for preparation vial.
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Yttrium chloride solution (1850 MBq/mL, 1 mL).
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Sterile vial for preparation.
Labeling method of this drug (outline)
Confirmation of radiochemical purity
Radioactivity administered
Administration methods (outline)
Protection from exposure
Protection from exposure before administration (during preparation) and during administration
Basic matters
Precautions for controlled areas
Preparation of protective equipment
Protection from exposure during preparation
Protection from exposure during administration
Protection from exposure during disposal of radioactive waste after administration
Testing for contamination and decontamination after administration
Testing for contamination and decontamination in rooms where this drug is used (walls and floor)
Exposure to medical personnel (external exposure and internal exposure)
Stage | Effective dose (per procedure) | Skin dose (per procedure) | Dose limits | |||||
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Time procedures take (min) | Distance (cm) | Exposure dose (mSv) | Time procedures take (min) | Distance (cm) | Exposure dose (mSv) | Effective dose limit (whole body) | Equivalent dose limit (skin) | |
Preparation | 20 | 50 | 0.00218 | 20 | 1.0 | 5.46 | Radiology technologists and technicians: 50 mSv/year 100 mSv/5 years Women of childbearing potential: 5 mSv/3 months | 500 mSv/year |
Administration | 20 | 50 | 0.00218 | 20 | 1.0 | 5.46 |
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C = 3700 × 106 × 0.001 × 1/(560 × 106 × 8 × 5) = 1.65 × 10−4 (Bq/cm3),
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I = 1.2 × 106 × C × 0.333 × 1 = 65.93 (Bq),
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E = e × I = 1.6 × 10−6 × 65.93 = 1.05 × 10−4 (mSv) = 0.105 (μSv).
Training
Training through the workshop on radiation safety handling
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Laws and ordinances, notification items, and release criteria.
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Safety management of radiopharmaceuticals for internal radiotherapy.
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Measurement of radioactivity and safe management of radioactive waste.
Education and training on preparation of this drug
Records of training
Release of patients administered a radiopharmaceutical
Release criteria for patients administered a radiopharmaceutical
Nuclides used in therapy | Dose or level of residual radioactivity in the body (MBq) |
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Strontium-89 | 200a |
Iodine-131 | 500b |
Yttrium-90 | 1184a |
Nuclides used in therapy | 1-cm dose equivalent rate 1 m from the surface of the patient’s body (μSv/h) |
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Iodine-131 | 30a |
Nuclides used in therapy | Scope | Dose (MBq) |
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Iodine-131 | Destruction of residual thyroid tissue (ablation) after a complete thyroidectomy to treat differentiated thyroid cancer with no distant metastasisa | 1110b |
Radium-223 | Treatment of castration-resistant prostate cancer with bone metastasisc | 12.1d (72.6)e |
Factors related to the evaluation of release criteria
Precautions after administration
Release of patients administered this drug
Exposure dose for a third party from a patient administered this drug
Evaluation of the dose from external exposure
Evaluation of the dose from internal exposure
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The average flow of the Yodo River water system: about 4.1 [TL/year].
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Population of the metropolitan Osaka area that obtains potable water from the water system: about 13.935 million (2015) (Osaka Prefecture + Nara Prefecture + Wakayama Prefecture + 1/2 of Hyogo Prefecture) [25].
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Total population of Japan: about 127.095 million (2015) [25].
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Population of the metropolitan Osaka area as a proportion of Japan’s total population: 10.96% (0.11).
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Number of patients with P-cadherin-positive recurrent solid cancer (ovarian cancer, bile duct cancer, head and neck cancer) in Japan: about 45,000 [person/year].
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Of the above, patients administered this product are estimated to be 10% or less: 4500 [person/year].
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Number of patients to be treated in the metropolitan Osaka area: 4500 × 0.11 = 495 patients (calculated by population ratio).
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Of note, 0.11 is the population ratio of the metropolitan Osaka area. Furthermore, it is assumed that one patient will receive 2220 MBq of this drug four times a year.
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Level of radioactivity of the total dose of this drug administered to patients in Osaka:2220 [MBq/dose] × 4 [time/person] × 495 [person] = 4.396 [TBq].
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It is assumed that all of this drug is discharged into the Yodo River water system, and that all of them exist in a water-soluble form.
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Concentration of this drug in the river:4.396 [TBq/year] ÷ 4.1 [TL/year] = 1.072 [Bq/L].Here, 4.1 TL is the annual average flow of the Yodogawa River water system.
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Annual intake of this drug per member of the general public (assuming 2 L of water for drinking per day) [26]:$$1.072\,[{\text{Bq}}/{\text{L}}] \times 2\,[{\text{L}}/{\text{day}}] \times 365\,[{\text{day}}/{\text{year}}] = 782.6\,[{\text{Bq}}/{\text{year}}].$$
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In the aforementioned instance, the dose from internal exposure in 1 y:782.6 [Bq/year] × 2.7 × 10−6 [mSv/Bq] ≈ 2.11 [μSv/year].Here, 2.7 × 10−6 [mSv/Bq] is the effective dose coefficient [15] for oral intake of 90Y.
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The internal exposure dose of 2.11 μSv per year is 0.21% of 1 mSv per year, the ICRP recommended exposure dose limit for the general public.
Comprehensive evaluation of the doses from external and internal exposure
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Exposure dose for caregivers = 1.080 [mSv] + 2.11 [μSv] = 1.082 [mSv].
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Exposure dose for the general public = 0.540 [mSv] + 2.11 [μSv] = 0.542 [mSv].
Criteria for release of a patient administered this drug from RI-controlled facility, etc.
Example of assessment of external exposure to family members (caregivers) and the general public
Distance (m) | Time (h/day) | Frequency (time/week) | Exposure dose (mSv) | ||
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(1 dose) | (4 doses/year) | ||||
In-home contact | 1 | 6 | 7 | 0.136 | 0.546 |
Sleeping in the same room | 1 | 8 | 7 | 0.182 | 0.728 |
Third party in the workplace | 1 | 8 | 5 | 0.130 | 0.520 |
Third party when commuting | 0.3 | 1 | 5 | 0.181 | 0.722 |