Section 302.657 Determining
the Human Nonthreshold Criterion
The HNC is calculated according
to the equation:
HNC
= RAI/[W + (F x BCF)]
where:
HNC
|
=
|
Human
Nonthreshold Protection Criterion in milligrams per liter (mg/L);
|
RAI
|
=
|
Risk
Associated Intake of a substance in milligrams per day (mg/d) that is
associated with a lifetime cancer risk level equal to a ratio of one to
1,000,000 as derived in Section 302.654;
|
W
|
=
|
Per capita
daily water consumption equal to 2 liters per day (L/d) for surface waters at
the point of intake of a public or food processing water supply, or equal to
0.01 liters per day (L/d) which represents incidental exposure through
contact or ingestion of small volumes of water while swimming or during other
recreational activities for areas which are determined to be public access
areas under Section 302.102(b)(3), or 0.001 liters per day (L/d) for other
waters;
|
F
|
=
|
Assumed
daily fish consumption in the United States equal to 0.020 kilograms per day (kg/d);
and
|
BCF
|
=
|
Aquatic
Life Bioconcentration Factor with units of liter per kilogram (L/kg) as
derived in Section 302.663.
|
(Source: Amended at 47 Ill.
Reg. 4437, effective March 23, 2023)