ERF of PCB on cancer

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Scope

ERF of PCB on cancer describes the quantitative relationship between exposure to polychlorinated biphenyls(PCBs) and cancer risk in adults.

Definition

ERF of PCB on cancer indexed by variable age. It applies to the last two age categories, i.e. 18-55yr, 55yr+ (gender combined).

Causality

Data

The U.S. Environmental Protection Agency (US EPA) recommends using cancer slope factors (CSFs) when evaluating potential cancer risks of PCB mixtures.[1] There are three tiers of CSFs for environmental PCBs that depend on the exposure pathway. These are: high risk and persistence, low risk and persistence, lowest risk and persistence. In each of these tiers EPA reports central and upper bound estimate of CSF. In general, central estimate slope factors are used to estimate a typical individual’s risk while upper-bound slope assure that this risk is not likely to be underestimated if the underlying model is correct.

According to the US EPA exposures via food chain are associated with the highest risk and persistence. Therefore CSFs from the first tier are recommended to be used when estimating cancer risks from food chain pathways.

Formula

Unit

(mg/kg bw/d)-1

Result

Upper bound slope factor Central-estimate slope factor
High risk and persistence 2.0 1.0
Low risk and persistence 0.4 0.3
Lowest risk and persistence 0.07 0.04

In Beneris slope factor of 2 is used.

References