Difference between revisions of "Multistage model"
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− | The | + | The '''multistage model''' is a dose-response model that attempts to reflect the biological process of carcinogenesis. |
P(Response|Dose)= background +(1-background)*(1-exp(-q1*Dose -q2*Dose^2 -q3*Dose^3...)) | P(Response|Dose)= background +(1-background)*(1-exp(-q1*Dose -q2*Dose^2 -q3*Dose^3...)) | ||
− | [[Category: | + | |
− | [[Category: | + | |
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+ | A more simple | ||
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+ | |||
+ | the formula for (excess) risk is: | ||
+ | |||
+ | |||
+ | P(dose) = 1 - exp [-alfao +alfa1 * | ||
+ | |||
+ | |||
+ | dose1 +...alfak * dose] | ||
+ | |||
+ | (alfa=dose-response) | ||
+ | |||
+ | |||
+ | |||
+ | |||
+ | At | ||
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+ | risk levels (<10-2) the following linear formula can be used for the upper bound (95%) risk | ||
+ | |||
+ | Risk = exposure (mg/kg/day) * q1 (risk per mg/kg/day) | ||
+ | |||
+ | q1=cancer slope factor, upper 95% confidence limit, | ||
+ | |||
+ | |||
+ | calculated from 10% point of departure (POD) | ||
+ | |||
+ | |||
+ | from experimental data | ||
+ | |||
+ | |||
+ | See e.g. Casarett & Doull's Toxicology | ||
+ | |||
+ | |||
+ | , 6th ed. 2001, p. 95-97. | ||
+ | |||
+ | [[Category:Health_effects]] [[Category:Needs_editing]] |
Revision as of 07:29, 27 March 2008
The multistage model is a dose-response model that attempts to reflect the biological process of carcinogenesis.
P(Response|Dose)= background +(1-background)*(1-exp(-q1*Dose -q2*Dose^2 -q3*Dose^3...))
A more simple
the formula for (excess) risk is:
P(dose) = 1 - exp [-alfao +alfa1 *
dose1 +...alfak * dose]
(alfa=dose-response)
At
risk levels (<10-2) the following linear formula can be used for the upper bound (95%) risk
Risk = exposure (mg/kg/day) * q1 (risk per mg/kg/day)
q1=cancer slope factor, upper 95% confidence limit,
calculated from 10% point of departure (POD)
from experimental data
See e.g. Casarett & Doull's Toxicology
, 6th ed. 2001, p. 95-97.