Using the biological two-stage model to assess risk from short-term exposures

Journal Article · Wed Jun 01 00:00:00 EDT 1988 · Risk Anal.; (United States)

DOI:https://doi.org/10.1111/j.1539-6924.1988.tb01175.x· OSTI ID:6148224

Chen, J J; Kodell, R L; Gaylor, D W

Two assumptions used in risk assessment are investigated: (1) the assumption of fraction of lifetime dose rate assumes that the risk from a fractional lifetime exposure at a given dose rate is equal to the risk from full lifetime exposure at that same fraction of the given dose rate; (2) the assumption of fraction of lifetime risk assumes that the risk from a fractional lifetime exposure at a given dose rate is equal to that same fraction of the risk from full lifetime exposure at the same dose rate. These two assumptions are equivalent when risk is a linear function of dose. Thus both can be thought of as generalizations of the assumption that cancer risk is proportional to the total accumulated lifetime dose (or average daily dose), which is often made to assess the risk from short-term exposures. In this paper, the age-specific cumulative hazard functions are derived using the two-stage model developed by Moolgavkar, Venzon, and Knudson for situations when the exposure occurs during a single period or at a single instant. The two assumptions described above are examined for three types of carcinogens, initiator, completer, and promoter, in the context of the model. For initiator and completer, these two assumptions are equivalent in the low-dose region; for a promoter, using the fraction of lifetime risk assumption is generally more conservative than that of the fraction of lifetime doser rate assumption.

• Research Organization: Food and Drug Administration, Jefferson, AR (USA)
• OSTI ID: 6148224
• Journal Information: Risk Anal.; (United States), Vol. 8:2
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CARCINOGENS
BIOLOGICAL EFFECTS
DOSE RATES
RISK ASSESSMENT
ENVIRONMENTAL EXPOSURE
AGE DEPENDENCE
AGE GROUPS
BIOLOGICAL ACCUMULATION
CARCINOGENESIS
CHRONIC EXPOSURE
COMPARATIVE EVALUATIONS
HEALTH HAZARDS
HUMAN POPULATIONS
LIFE SPAN
MATHEMATICAL MODELS
NEOPLASMS
TIME DEPENDENCE
TUMOR PROMOTERS
DISEASES
HAZARDS
PATHOGENESIS
POPULATIONS
PROMOTERS
560300* - Chemicals Metabolism & Toxicology