Table 5 -17. Early Bioassay Measurement Results Corresponding to the Therapeutic Intervention

DOE-STD-1136-2004

Guide of Good Practices for Occupational Radiological Protection in Uranium Facilities

For acute intakes, direct bioassay measurements should be taken before, during, and after the period of

rapid clearance of activity. Urine and fecal samples collected after known or suspected inhalation incidents

should also be used to estimate the magnitude of the intake. Initial assessments of intakes from

contaminated wounds are based primarily on wound count and urinalysis data.

If a significant intake is indicated, the worker should not return to further potential exposure to

uranium until the intake has been thoroughly assessed and a predictable bioassay pattern established.

This is particularly important because a new intake of a very low level may confound the interpretation

of bioassay measurements for previous intakes of uranium.

Table 5 -17. Early Bioassay Measurement Results Corresponding to the Therapeutic Intervention

Action Levels Used at the Hanford Site (Carbaugh et al., 1995)

Isot ope and Dose

Possible

Measurement

Result

Action

(HE,50)

Treatment

Uranium, Soluble

Potential kidney

Na or Ca bicarbonate;

Chest count

>MDA (14-21 mg)

Consider therapy

toxicity

intestinal adsorbents

Second-void urine

>0.1 mg

sample

12-hour urine sample

>0.5 mg

Uranium Insoluble(a)

235

U or

2 rem

Chest count

>MDA for

Consider therapy

None recommended

234

Treatment strongly

200 rem

Same

100 x ALI

Lung lavage

recommended

(a) If soluble component is present, then urine sampling is approp riate. Use same action levels as above for soluble uranium.

The health physicist must make important decisions for prompt action at the site of an accidental or

suspected intake of uranium or other radioactive materials. Often, these decisions must be based on

limited data. Information that may be available for initially estimating the amount and type of intake may

include the following:

levels of measured contamination in the work area,

skin contamination levels, affected areas, and whether the skin is damaged or punctured,

wound contamination levels,

chemical form of the material involved,

results of air monitoring,

nasal smear activity levels, and

sputum and/or mouth contamination.

The special bioassay monitoring program is initiated following a known or suspected intake. This

information is needed for dose assessment and future exposure management. The intake is confirmed if

follow-up bioassay measurements indicate positive measurement results. Additional bioassay

measurements may be needed to quantify the intake and provide data for determining the effective dose

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