Practical action levels for chelation therapy in plutonium inhalation using nose swab

Area of Science:

• Radiological Protection
• Occupational Health
• Nuclear Medicine

Background:

• Inhalation of plutonium compounds poses significant health risks in occupational settings.
• Early detection and intervention are crucial for managing internal plutonium contamination.
• Nose swabs offer a non-invasive method for assessing initial exposure.

Purpose of the Study:

• To propose action levels for initiating chelation therapy following plutonium inhalation.
• To establish a correlation between plutonium activity detected in nose swabs and early fecal excretion.
• To provide practical guidance for JAEA-NFCEL facilities.

Main Methods:

• Analysis of actual cases at JAEA-NFCEL to determine the relationship between nose swab activity and fecal excretion.
• Statistical analysis to characterize the distribution of the ratio between these two measurements.
• Determination of action levels based on established dose limits (10 ALI = 200 mSv).

Main Results:

• A log-normal distribution was identified for the ratio of nose swab activity to early fecal excretion.
• Action levels were determined for JAEA-NFCEL facilities, considering plutonium isotopic ratios and physicochemical properties.
• The study provides a quantitative basis for timely chelation therapy decisions.

Conclusions:

• Nose swab activity is a reliable indicator for early assessment of plutonium inhalation.
• The established action levels facilitate prompt and effective chelation therapy interventions.
• This research enhances safety protocols for handling plutonium compounds in nuclear facilities.