Dose Commitment = C

k

If exposure (inhalation) should stop at time t, the additional dose (Day)

Dp = RD.Q,

0.6

a

TeexpChyt)

t-

An

*

og at
NF

(6)

delivered to subcompartment k by the radionuclide present at time t would be
T-t

Da (RfDQ A) l-exp(-a tt) P

.

exp(-h, (T-t) de

Pare Ryfgy Ay) CL-exp (A, #)) [T-exp (a, (Tot) ) Ag f

C, = RD.Q)

k

=D,

k

+ D

l-exp(-A, t)

t - —* exp(-A, (T-t)

)

: aut |
x

where T is any time subsequent to t, i.e., T>t
Cc,

0.6 (

x

a

£

Ak

THORACIC LYMPH NODES

1-exp(-A, €)

Oo RE D/A Lee TO exp (A (T-E))]
k

(3)
The thoracic lymph nodes (L) receive radionuclide from Ph at the biological
elimination rate, ”,

For class Y compounds, there are two subcompartments, Li and Lr.
EQUATIONS USED FOR NTS PLUTONIUM MODEL.

1.4 receives

90 percent of the radionuclide in qh and transfers it to B at the biological
elimination rate, ve

The remaining 10 percent is retained in Lr from which

it is lost by radioactive decay, Mae only.
Pulmonary Region = Lungs
Q L = Qa, Li + Q Lr

Qp = Dez (E/A,) C-exp(-agt)) © (fp/0 ) (L-exp(-ht))
+ (£ fh_)Cl-exp(-A,t)) +

go 8

8

(£/\_)(L-exp(-2,t))1

hoh

h

As he = he = Aw f, + ft + fi, = 0.6, and fe. = 0.4, Eq.

Q, = Da,

L-exp(-A, t)

(4)

(4) reduces to

dQ

.

—

Qe

reece? |

dQ

aH
ena
= ichch
Po SHE
= cee ih
abn
dt
ioLi
dt
rLr
-

=f Fh nQ/ s tas;

—_

Qo

=

b-

S
CL-£ (1-f AL, / (Sea)

0.6 —, + 0.4 he

Qa. £,D,9,/5(S+a,)

For t 2 10, L-exp(-) ,t) - 1, and
.
_
Q =- D.o, [0.6 (1-exp(
AEA, + 0.4/4]
is an accurate approximation,

696

(5)

=

_,b
fy
Vf
—_—
Q = Af D 25S retvery
+ —————+__
S(SA, SA)

(8)

Select target paragraph3