Protocol for the Derivation of Environmental and Human ... - CCME

Appendix B
carcinogenic, then the total exposure should not exceed the risk specific dose for a cancer risk of 10 -6 .
The equations for this estimation are given in the following Section 4.1.
4.1 Non-carcinogens
Agricultural Site
For an agricultural site, the Subcommittee proposed that 100% of the milk, and 50% of garden produce
and meat are produced or grown on site. The total intake of contaminant is calculated based on these
assumptions. These estimates provide the total (background and on-site) exposure from those food
sources. Generic guidelines for an agricultural setting are assumed to protect against exposure from local
garden produce, and meat and milk.
I p = intake of contaminant from produce grown on-site + intake of contaminant from produce
grown off-site
I b = intake of contaminant from meat produced on-site + intake of contaminant from meat
produced off-site
I m = intake of contaminant from milk produced on-site + intake of contaminant from milk
produced off site
In estimating the total intake of a contaminant from all food sources at an agricultural site, the
background intake of produce, meat, and milk must be removed because the above equations include
on-site and off-site exposure.
Where:
T R = T F - (I BP + I BB + I BM ) [12]
T R = Total estimated intake of contaminant from food other than produce, meat, and
milk
T F = Total estimated intake of contaminant from food (from multi-media exposure
assessment)
I BP = Background intake of contaminant in produce (from multi-media exposure
assessment)
I BB = Background intake of contaminant in meat (from multi-media exposure
assessment)
I BM = Background intake of contaminant in milk (from multi-media exposure
assessment)
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