Response to Suspected Intakes - doe-std-1128-98

DOE-STD-1128-98

-- When the estimated intake exceeds 10 times the ALI, then extended or protracted

treatment should be implemented, except for materials poorly transported from the

lung.

-- For poorly transported material in the lung, lung lavage is the only recommended

treatment, and it is only a consideration for intakes exceeding 100 times the ALI.

Because the dose associated with the ALI in the CEC/DOE Guidebook is 2-rem CEDE and

because the upper administrative level recommended by the standard, Radiological Control,

is 2 rem, intervention levels of 2 rem and 20 rem might be used for guidance in the manner

presented in the CEC/DOE Guidebook:

-- When the CEDE estimated intake is below 2 rem, treatment is not generally

recommended.

-- When the CEDE for an estimated intake is between 2 rem and 20 rem, treatment should

be considered. Under these situations, short-term administration will usually be

appropriate.

-- When the CEDE equivalent for an estimated intake exceeds 20 rem, then extended or

protracted treatment is strongly recommended, except for poorly transported material in

the lung.

Decorporation therapy should be administered immediately following any suspected intake

or accidental internal contamination in excess of established action levels. The extent and

magnitude of an internal plutonium contamination usually cannot be determined quickly;

however, the usefulness of therapy will diminish if plutonium is allowed to translocate to

bone where DTPA is ineffective. La Bone (1994b) has provided a recent approach to

evaluating urine data enhanced by chelation (DTPA) therapy.

An initial prophylactic chelation therapy may be appropriate because bioassay

measurements (particularly urinalysis) cannot usually be completed within the response

time required for effective chelation therapy. Urinalysis becomes very helpful following

administration of chelation therapy because there is a direct correlation between DTPA,

urinary excretion, and dose averted because of plutonium excreted. Bihl (1994) has shown

that about 2 mrem of CEDE is averted for every dpm of 239Pu excreted. This provides a

method of measuring the effectiveness of DTPA therapy and determining if it is worthwhile

to continue therapy. For example, if DTPA is administered when untreated excretion is 2

dpm/d, excretion should increase to 20 to 100 dpm for a dose savings of 40- to 200-mrem/d

CEDE. It is probable that the efficacy of treatment will decrease with continued

administration as plutonium is removed from the liver and the rate of transfer into the

systemic compartment decreases.

5.10 RESPONSE TO SUSPECTED INTAKES

Experience has shown that most intakes of plutonium are accidental. Plutonium facilities

and operating procedures are designed to prevent intakes. Nonetheless, it is important for

management to prepare for the possibility that workers might receive an intake of

plutonium--even though the probability of an incident may be very small. Prompt and

appropriate action following an accidental intake of plutonium will allow for therapeutic

measures to be taken to minimize the internal contamination and lessen the potential for

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